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Masilayidi owonetsa zolemba zitatu pa slide iliyonse.Gwiritsani ntchito mabatani akumbuyo ndi ena kuti mudutse zithunzi, kapena mabatani owongolera masilayidi kumapeto kuti mudutse silayidi iliyonse.
Zawonetsedwa posachedwa kuti kugwiritsa ntchito ma ultrasound kumatha kupititsa patsogolo zokolola za minofu mu ultrasound-enhanced fine needle aspiration biopsy (USeFNAB) poyerekeza ndi ochiritsira fine needle aspiration biopsy (FNAB).Ubale pakati pa bevel geometry ndi singano nsonga ya singano sunafufuzidwebe.Mu kafukufukuyu, tidafufuza za mawonekedwe a singano ndi matalikidwe opindika amitundu yosiyanasiyana ya singano ya singano yokhala ndi utali wosiyanasiyana wa bevel.Pogwiritsa ntchito lancet wamba yokhala ndi 3.9 mm yodulidwa, nsonga yamagetsi yamagetsi (DPR) inali 220 ndi 105 µm/W mumlengalenga ndi madzi, motsatana.Izi ndizokwera kuposa nsonga ya axisymmetric 4mm bevel, yomwe idapeza DPR ya 180 ndi 80 µm/W mumlengalenga ndi madzi, motsatana.Kafukufukuyu akuwonetsa kufunikira kwa ubale pakati pa kuuma kopindika kwa bevel geometry pokhudzana ndi zida zosiyanasiyana zoyika, ndipo motero atha kupereka chidziwitso panjira zowongolera zochita zodulira pambuyo pobaya posintha singano ya bevel geometry, yomwe ndi yofunika kwa USeFNAB.Ntchito ndi yofunika.
Fine needle aspiration biopsy (FNAB) ndi njira yomwe singano imagwiritsidwira ntchito kupeza chitsanzo cha minofu pamene akuganiza kuti pali vuto1,2,3.Maupangiri amtundu wa Franseen awonetsedwa kuti amapereka magwiridwe antchito apamwamba kuposa malangizo achikhalidwe a Lancet4 ndi Menghini5.Ma bevel a axisymmetric (ie circumferential) aperekedwanso kuti awonjezere mwayi wokhala ndi zitsanzo zokwanira za histopathology6.
Pa biopsy, singano imadutsa pakhungu ndi minofu kuti iwonetse matenda okayikitsa.Kafukufuku waposachedwapa wasonyeza kuti akupanga kutsegula kungathe kuchepetsa puncture mphamvu zofunika kupeza zofewa zimakhala7,8,9,10.Needle bevel geometry yasonyezedwa kuti imakhudza mphamvu yolumikizana ndi singano, mwachitsanzo, ma bevel aatali awonetsedwa kuti ali ndi mphamvu zochepa zolowera minofu 11.Zanenedwa kuti singano ikalowa m'kati mwa minofu, mwachitsanzo, pambuyo pobowola, mphamvu yodulira ya singano ikhoza kukhala 75% ya mphamvu yonse yolumikizana ndi singano12.Ultrasound (US) yasonyezedwa kuti ipititse patsogolo khalidwe la matenda ofewa a biopsy mu post-puncture phase13.Njira zina zowonjezeretsa khalidwe la fupa la fupa zapangidwa kuti zikhale zolimba za sampling14,15 koma palibe zotsatira zomwe zanenedwa kuti zimapangitsa kuti biopsy ikhale yabwino.Kafukufuku wambiri wapezanso kuti kusamuka kwamakina kumawonjezeka ndikuwonjezeka kwa ultrasound drive voltage16,17,18.Ngakhale pali maphunziro ambiri a axial (longitudinal) static mphamvu mu singano-tissue interactions19,20, maphunziro a temporal dynamics ndi singano bevel geometry mu akupanga kumatheka FNAB (USeFNAB) ndi ochepa.
Cholinga cha phunziroli chinali kufufuza zotsatira za ma bevel geometries pa singano nsonga zochita moyendetsedwa ndi singano flexion pa akupanga ma frequency.Makamaka, tidafufuza momwe jakisoniyo amakhudzira nsonga ya singano pambuyo pobaya ma bevel a singano (mwachitsanzo, ma lancets), axisymmetric ndi asymmetric single bevel geometries (mku. kulowa kapena minyewa yofewa.
Mitundu yosiyanasiyana ya bevel idaphatikizidwa mu kafukufukuyu.(a) Ma Lanceti ogwirizana ndi ISO 7864:201636 pomwe \(\ alpha\) ndi ngodya yoyambira ya bevel, \(\theta\) ndi ngodya yachiwiri ya bevel, ndipo \(\phi\) ndi ngodya yachiwiri ya bevel mu madigiri , mu madigiri (\(^\circ\)).(b) mzere wa asymmetrical single step chamfers (otchedwa "standard" mu DIN 13097:201937) ndi (c) linear axisymmetric (circumferential) single step chamfers.
Njira yathu ndikuyamba kutengera kusintha kwa kutalika kwa mafunde opindika motsetsereka kwa ma lancet wamba, axisymmetric, ndi ma asymmetric single-site slope geometries.Kenako tidawerengera kafukufuku wa parametric kuti tiwone momwe ma bevel angle ndi kutalika kwa chubu kumayendera.Izi zimachitika kuti mudziwe kutalika koyenera kupanga singano ya prototype.Kutengera kuyerekezera, ma prototypes a singano adapangidwa ndipo machitidwe awo owoneka bwino mumpweya, m'madzi, ndi 10% (w / v) ballistic gelatin adayesedwa moyesa kuyeza koyezetsa kowoneka bwino komanso kuwerengera mphamvu yosinthira mphamvu, komwe ma frequency amagwirira ntchito. wotsimikiza..Pomaliza, kujambula kothamanga kwambiri kumagwiritsidwa ntchito kuyeza mwachindunji kupotoza kwa mafunde opindika pansonga ya singano mumlengalenga ndi m'madzi, ndikuyerekeza mphamvu yamagetsi yomwe imaperekedwa ndi kupendekeka kulikonse ndi geometry yamagetsi yamagetsi (DPR) ya jekeseni. wapakati.
Monga momwe tawonetsera pa Chithunzi 2a, gwiritsani ntchito chitoliro cha No. 21 (0.80 mm OD, 0.49 mm ID, makulidwe a khoma la chitoliro cha 0.155 mm, khoma lokhazikika monga momwe ISO 9626:201621) limapangidwira zitsulo zosapanga dzimbiri 316 ( Young's modulus 205).\(\ zolemba {GN/m}^{2}\), kusachulukira 8070 kg/m\(^{3}\), chiŵerengero cha Poisson 0.275).
Kutsimikiza kwa utali wopindika ndikusintha kwa finite element model (FEM) ya singano ndi malire.(a) Kutsimikiza kwa kutalika kwa bevel (BL) ndi kutalika kwa chitoliro (TL).(b) Atatu-dimensional (3D) finite element model (FEM) pogwiritsa ntchito harmonic point force \(\tilde{F}_y\vec{j}\) kukweza singano kumapeto kwa proximal, kupotoza mfundoyo, ndi kuyeza liwiro. pa nsonga iliyonse (\( \tilde{u}_y\vec {j}\), \(\tilde{v}_y\vec {j}\)) kuti muwerengere mayendedwe amakanika.\(\lambda _y\) imatanthauzidwa ngati utali wopindika womwe umagwirizanitsidwa ndi mphamvu yoyimirira \(\tilde{F}_y\vec {j}\).(c) Dziwani zapakati pa mphamvu yokoka, gawo lopingasa A, ndi mphindi za inertia \(I_{xx}\) ndi \(I_{yy}\) mozungulira x-axis ndi y-axis motsatana.
Monga momwe tawonetsera mkuyu.2b, c, kwa mtengo wopandamalire (wopanda malire) wokhala ndi gawo lozungulira A komanso pamtunda waukulu poyerekeza ndi kukula kwa gawo la mtanda wa mtengowo, kuthamanga (kapena kupinda) gawo \(c_{EI}\) ) akufotokozedwa ngati 22:
pomwe E ndi Young's modulus (\(\text {N/m}^{2}\)), \(\omega _0 = 2\pi f_0\) ndi mafupipafupi a angular (rad/s), pamene \( f_0 \ ) ndi liniya pafupipafupi (1/s kapena Hz), ine ndi mphindi ya inertia wa dera mozungulira axis chidwi \ ((\ text {m}^{4})\) ndi \(m'=\) rho _0 A \) ndi unyinji pa utali wa unit (kg/m), pamene \(\rho _0\) ndi kachulukidwe \((\text {kg/m}^{3})\) ndi A ndiye mtanda -gawo la mtengo (ndege ya xy) (\ (\ zolemba {m}^{2}\)).Popeza kwa ife mphamvu yogwiritsidwa ntchito ikufanana ndi y-axis yowongoka, mwachitsanzo \(\tilde{F}_y\vec {j}\), timangosangalatsidwa ndi mphindi ya inertia ya dera lozungulira x- olamulira, ndiye \(I_{xx} \), chifukwa chake:
Kwa finite element model (FEM), kusamuka koyera (m) kumaganiziridwa, kotero mathamangitsidwe (\(\text {m/s}^{2}\)) amawonetsedwa ngati \(\ partial ^2 \vec). {u}/ \ pang'ono t^2 = -\omega ^2\vec {u}\), mwachitsanzo \(\vec {u}(x, y, z, t) := u_x\vec {i} + u_y \ vec {j }+ u_z\vec {k}\) ndi mawonekedwe atatu osunthika omwe amafotokozedwa m'malo olumikizirana.Kusintha chomalizacho ndi mawonekedwe opunduka a Lagrangian a momentum balance law23, malinga ndi kukhazikitsidwa kwake mu pulogalamu ya COMSOL Multiphysics software (mitundu 5.4-5.5, COMSOL Inc., Massachusetts, USA), imapereka:
Kumene \(\vec {\nabla}:= \frac{\partial}}{\partial x}\vec {i} + \frac{\partial}}{\partial y}\vec {j} + \frac{ \partial }{\ partial z}\vec {k}\) ndiye woyendetsa ma tensor divergence, ndipo \({\ underline{\sigma}}\) ndi yachiwiri ya Piola-Kirchhoff stress tensor (dongosolo lachiwiri, \(\ text {N /m}^{2}\)), ndi \(\vec {F_V}:= F_{V_x}\vec {i}+ F_{V_y}\vec {j}+ F_{V_z}\vec { k} \) ndi vector of the body force (\(\text {N/m}^{3}\)) ya voliyumu iliyonse yopunduka, ndipo \(e^{j\phi}\) ndi gawo la mphamvu ya thupi, ili ndi mbali ya gawo \(\ phi\) (rad).Kwa ife, kuchuluka kwa mphamvu ya thupi ndi ziro, ndipo chitsanzo chathu chimatengera mzere wa geometric ndi zotupa zazing'ono, mwachitsanzo \({\ underline{\ varepsilon}} ^ {el} = {\ underline{\ varepsilon}}\ ), kumene \({\ underline{\ varepsilon}}}^{el}\) ndi \({\ underline{\varepsilon}}\) - elastic deformation and total deformation (dimensionless of the second order), motero.Hooke's constitutive isotropic elasticity tensor \(\ underline {\ underline {C))\) imapezeka pogwiritsa ntchito Young's modulus E(\(\text{N/m}^{2}\)) ndi Poisson's ratio v imatanthauzidwa, kotero kuti \ (\ underline{\ underline{C}}:=\ underline{\ underline{C}}(E,v)\) (mzere wachinayi).Chifukwa chake kuwerengera kupsinjika kumakhala \({\ underline{\sigma}} := \ underline{\ underline{C}}:{\ underline{\varepsilon}}}).
Kuwerengera kunachitika ndi ma 10-node tetrahedral element ndi element size \(\le\) 8 µm.Singano imapangidwa mu vacuum, ndipo mtengo wosinthira makina (ms-1 H-1) umatanthauzidwa kuti \(|\tilde{Y}_{v_yF_y}|= |\tilde{v}_y\vec {j} || F} _y\vec {j}\) ndizovuta zoyendetsa galimoto zomwe zili kumapeto kwenikweni kwa chubu, monga momwe tawonetsera pa Chithunzi 2b.Transmissive mechanical movement imawonetsedwa mu ma decibel (dB) pogwiritsa ntchito mtengo wapamwamba kwambiri monga mawu, mwachitsanzo \(20\log _{10} (|\tilde{Y}|/ |\tilde{Y}_{max}| )\ ), Maphunziro onse a FEM adachitika pafupipafupi 29.75 kHz.
Mapangidwe a singano (mkuyu 3) ali ndi singano wamba 21 gauge hypodermic singano (kalozera nambala: 4665643, Sterican \ (^\ circledR \), ndi m'mimba mwake 0.8 mm, kutalika 120 mm, zopangidwa AISI. chromium-nickel stainless steel 304., B. Braun Melsungen AG, Melsungen, Germany) anaika manja a pulasitiki a Luer Lock opangidwa ndi polypropylene proximal ndi kusintha kogwirizana ndi nsonga.Chubu cha singano chimagulitsidwa ku waveguide monga momwe tawonetsera mkuyu 3b.Chombocho chinasindikizidwa pa chosindikizira cha 3D chosapanga dzimbiri (EOS Stainless Steel 316L pa printer ya EOS M 290 3D, 3D Formtech Oy, Jyväskylä, Finland) ndipo kenako amangirizidwa ku sensa ya Langevin pogwiritsa ntchito mabawuti a M4.Transducer ya Langevin imakhala ndi mphete 8 za piezoelectric zokhala ndi zolemera ziwiri kumapeto kulikonse.
Mitundu inayi ya maupangiri (achithunzi), lancet yopezeka pamalonda (L), ndi atatu opangidwa axisymmetric single-stage bevels (AX1-3) anali ndi bevel lengths (BL) ya 4, 1.2, ndi 0.5 mm, motsatana.(a) Kutsekereza nsonga ya singano.(b) Mawonedwe apamwamba a zikhomo zinayi zogulitsidwa ku 3D yosindikizidwa yosindikizidwa ndikugwirizanitsa ndi sensor ya Langevin yokhala ndi ma bolt a M4.
Malangizo atatu a axisymmetric bevel (mkuyu 3) (TAs Machine Tools Oy) anapangidwa ndi kutalika kwa bevel (BL, yotsimikiziridwa mumkuyu 2a) ya 4.0, 1.2 ndi 0.5 mm, yofanana ndi \ (\ approx \) 2 \ (^\ circ\), 7\(^\circ\) ndi 18\(^\circ\).Kulemera kwa ma waveguide ndi stylus ndi 3.4 ± 0.017 g (kutanthauza ± SD, n = 4) kwa bevel L ndi AX1-3, motsatira (Quintix\(^\circledR\) 224 Design 2, Sartorius AG, Göttingen, Germany).Kutalika konse kuchokera ku nsonga ya singano mpaka kumapeto kwa manja apulasitiki ndi 13.7, 13.3, 13.3, 13.3 masentimita kwa bevel L ndi AX1-3 mu Chithunzi 3b, motsatana.
Pa masinthidwe onse a singano, kutalika kuchokera kunsonga kwa singano kupita kunsonga ya waveguide (ie, malo olumikizira) ndi 4.3 cm, ndipo chubu cha singano chimalunjika kuti bevulo liyang'ane mmwamba (ie, kufanana ndi Y axis). ).), monga mu (mkuyu 2).
Zolemba zokhazikika ku MATLAB (R2019a, The MathWorks Inc., Massachusetts, USA) zomwe zikuyenda pakompyuta (Latitude 7490, Dell Inc., Texas, USA) zidagwiritsidwa ntchito kupanga kusesa kwa sinusoidal kuchokera pa 25 mpaka 35 kHz mumasekondi 7, kusinthidwa kukhala chizindikiro cha analogi ndi chosinthira digito-to-analogi (DA) (Analog Discovery 2, Digilent Inc., Washington, USA).Chizindikiro cha analogi \(V_0\) (0.5 Vp-p) kenako chinakulitsidwa ndi amplifier odzipereka a wailesi (RF) (Mariachi Oy, Turku, Finland).Magetsi akugwa \({V_I}\) amatuluka kuchokera ku RF amplifier yokhala ndi cholepheretsa cha 50 \ (\ Omega \) kupita ku thiransifoma yomangidwa mu singano yokhala ndi cholepheretsa cha 50 \ (\ Omega) \) Langevin transducer (ma transducer akutsogolo ndi kumbuyo a multilayer piezoelectric transducers, odzaza ndi misa) amagwiritsidwa ntchito kupanga mafunde amakina.RF amplifier yachizolowezi imakhala ndi mita yamagetsi yamagetsi (SWR) yomwe imatha kuzindikira zomwe zikuchitika \({V_I}\) ndikuwonetsa ma voltage amplified \(V_R\) kudzera pa 300 kHz analog-to-digital (AD ) chosinthira (Analog Discovery 2).Chizindikiro chosangalatsa chimasinthidwa koyambirira komanso kumapeto kuti chiteteze kuchulukitsitsa kwa amplifier ndi zodutsa.
Pogwiritsa ntchito script yomwe yakhazikitsidwa mu MATLAB, frequency reaction function (AFC), mwachitsanzo, imatengera njira yokhazikika.Komanso, gwiritsani ntchito fyuluta yodutsa 20 mpaka 40 kHz kuti muchotse ma frequency osafunika pa siginecha.Ponena za chiphunzitso cha mzere wa transmission, \(\tilde{H}(f)\) pamenepa ndi chofanana ndi voteji reflection coefficient, mwachitsanzo \(\rho _{V} \equiv {V_R}/{V_I} \)26 .Popeza kuti kutulutsa mphamvu kwa amplifier \ (Z_0 \) kumagwirizana ndi kulowetsedwa kwa chosinthira chosinthika chosinthika, ndipo mphamvu yowonetsera mphamvu yamagetsi \ ({P_R}/{P_I}\) imachepetsedwa kukhala \( {V_R }^ 2/{V_I}^2\ ) ofanana \ (|\rho _{V}|^2\).Ngati mtengo wokwanira wa mphamvu yamagetsi ukufunika, werengerani zomwe zidachitika \(P_I\) ndikuwonetsa\(P_R\) mphamvu (W) potenga muzu wotanthauza masikweya (rms) mtengo wa voteji yofananira, mwachitsanzo, kwa chingwe chopatsira chokhala ndi chikoka cha sinusoidal, \(P = {V}^2/(2Z_0)\)26, pamene \(Z_0\) ndi 50 \(\Omega\).Mphamvu yamagetsi yoperekedwa ku katundu \(P_T\) (ie sing'anga yoyikidwa) ikhoza kuwerengedwa ngati \(|P_I - P_R |\) (W RMS) ndipo mphamvu yotumizira mphamvu (PTE) ikhoza kufotokozedwa ndikufotokozedwa ngati peresenti (%) motero amapereka 27:
Kuyankha pafupipafupi kumagwiritsidwa ntchito kuyerekeza ma moduli \(f_{1-3}\) (kHz) a kalembedwe ka cholembera ndi mphamvu yofananira ndi kutumiza mphamvu, \(\mawu {PTE}_{1{-}3} \ ).FWHM (\(\text {FWHM}_{1{-}3}\), Hz) akuyerekezeredwa mwachindunji kuchokera \(\text {PTE}_{1{-}3}\), kuchokera mu Table 1 ma frequency \(f_{1-3}\) ofotokozedwa mu .
Njira yoyezera kuyankha pafupipafupi (AFC) ya kapangidwe ka acicular.Dual-channel swept-sine measurement25,38 imagwiritsidwa ntchito kupeza ma frequency yankho \(\tilde{H}(f)\) ndi kuyankha kwake H(t).\({\ masamu {F}}\) ndi \({\ masamu {F}}^{-1}\) amatanthawuza kusintha kwa manambala kwa Fourier ndi ntchito yosinthira motsatana.\(\tilde{G}(f)\) zikutanthauza kuti zizindikiro ziwirizi zikuchulukitsidwa mufupipafupi, mwachitsanzo \(\tilde{G}_{XrX}\) amatanthauza scan inverse\(\tilde{X} r( f )\) ndi chizindikiro chotsitsa voteji \(\tilde{X}(f)\).
Monga momwe tawonetsera mkuyu.5, kamera yothamanga kwambiri (Phantom V1612, Vision Research Inc., New Jersey, USA) yokhala ndi lens yayikulu (MP-E 65mm, \(f)/2.8, 1-5 \ (\times\), Canon Inc. ., Tokyo, Japan) adagwiritsidwa ntchito polemba kupotoza kwa singano ya singano yomwe imakhudzidwa ndi kugwedezeka kwa flexural (mafupipafupi, sinusoid yosalekeza) pafupipafupi 27.5-30 kHz.Kuti apange mapu amthunzi, chinthu chokhazikika cha LED yoyera kwambiri (gawo nambala: 4052899910881, White Led, 3000 K, 4150 lm, Osram Opto Semiconductors GmbH, Regensburg, Germany) idayikidwa kuseri kwa bevel ya singano.
Kuwonekera kutsogolo kwa khwekhwe loyesera.Kuzama kumayezedwa kuchokera pa media media.Mapangidwe a singano amamangika ndikuyikidwa patebulo lotengera mota.Gwiritsani ntchito kamera yothamanga kwambiri yokhala ndi lens yokulira kwambiri (5\(\times\)) kuti muyeze kupatuka kwa nsonga yopindika.Miyeso yonse ndi ma millimeters.
Pa mtundu uliwonse wa singano bevel, tinajambula 300 makamera othamanga kwambiri a 128 \(\x\) 128 pixels, iliyonse yokhala ndi mawonekedwe a 1/180 mm (\(\ approx) 5 µm), yokhala ndi kusintha kwakanthawi. mafelemu 310,000 pa sekondi imodzi.Monga momwe chithunzi 6, aliyense chimango (1) cropped (2) kotero kuti nsonga ili mu mzere wotsiriza (pansi) wa chimango, ndiyeno histogram wa fano (3) kuwerengeredwa, kotero Canny zipata 1 ndi 2 ikhoza kutsimikiziridwa.Kenako gwiritsani ntchito Canny28(4) kuzindikira m'mphepete pogwiritsa ntchito Sobel operator 3 \(\times\) 3 ndikuwerengera malo a pixel a non-cavitational hypotenuse (olembedwa \(\mathbf {\times}\)) pamasitepe onse 300. .Kuti mudziwe kutalika kwa kupatuka kumapeto, chotengeracho chimawerengedwa (pogwiritsa ntchito algorithm yosiyana yapakati) (6) ndipo chimango chomwe chili ndi malekezero amderalo (ie nsonga) ya kupatuka (7) chimadziwika.Pambuyo poyang'ana m'mphepete mwapang'onopang'ono, mafelemu awiri (kapena mafelemu awiri olekanitsidwa ndi theka la nthawi) (7) adasankhidwa ndipo nsonga yachitsulo imayesedwa (yotchedwa \(\ mathbf {\times} \ ) Zomwe zili pamwambazi zinakhazikitsidwa. mu Python (v3.8, Python Software Foundation, python.org) pogwiritsa ntchito OpenCV Canny edge diagnosis algorithm (v4.5.1, open source computer vision library, opencv.org) mphamvu yamagetsi \ (P_T \) (W, rms) .
Kupatuka kwa nsonga kunayesedwa pogwiritsa ntchito mafelemu angapo otengedwa kuchokera ku kamera yothamanga kwambiri pa 310 kHz pogwiritsa ntchito njira ya 7-step algorithm (1-7) kuphatikiza kupanga (1-2), Canny edge kuzindikira (3-4), m'mphepete mwa malo a pixel. kuwerengetsera (5) ndi zotengera nthawi (6), ndipo pamapeto pake kupatuka kwa nsonga mpaka pachimake kunayesedwa pamafelemu omwe amawunikiridwa ndi maso (7).
Miyezo inatengedwa mumlengalenga (22.4-22.9 ° C), madzi opangidwa ndi deionized (20.8-21.5 ° C) ndi ballistic gelatin 10% (w / v) (19.7-23.0 ° C, \ (\ text {Honeywell} ^ {\text) {TM}}\) \(\text {Fluka}^{\text {TM}}\) Gelatin ya Bovine ndi Pork Bone ya Type I Ballistic Analysis, Honeywell International, North Carolina, USA).Kutentha kunayesedwa ndi K-type thermocouple amplifier (AD595, Analog Devices Inc., MA, USA) ndi K-type thermocouple (Fluke 80PK-1 Bead Probe No. 3648 type-K, Fluke Corporation, Washington, USA).Kuchokera pakatikati Kuzama kunayesedwa kuchokera kumtunda (kukhazikitsidwa ngati komwe kumachokera z-axis) pogwiritsa ntchito siteji yoyimirira ya z-axis (8MT50-100BS1-XYZ, Standa Ltd., Vilnius, Lithuania) yokhala ndi 5 µm.pa sitepe.
Popeza kukula kwachitsanzo kunali kocheperako (n = 5) ndipo sizingaganiziridwe bwino, kuyesa kwamitundu iwiri ya Wilcoxon yamitundu iwiri (R, v4.0.3, R Foundation for Statistical Computing, r-project .org) inagwiritsidwa ntchito. kufananiza kuchuluka kwa singano ya singano yama bevel osiyanasiyana.Panali mafaniziro a 3 pa malo otsetsereka, kotero kuwongolera kwa Bonferroni kunagwiritsidwa ntchito ndi mulingo wofunikira wa 0.017 ndi cholakwika cha 5%.
Tiyeni tsopano titembenuzire ku Fig.7.Pafupipafupi 29.75 kHz, kupindika kwa theka (\(\lambda_y/2\)) kwa singano ya 21-gauge ndi \(\ pafupifupi) 8 mm.Munthu akamayandikira nsonga, kutalika kwa mafunde opindika kumachepa motsatira ngodya ya oblique.Pansonga \(\lambda _y/2\) \(\pafupifupi\) pali masitepe a 3, 1 ndi 7 mm a lanceolate wamba (a), asymmetric (b) ndi axisymmetric (c) kupendekera kwa singano imodzi. , motero.Choncho, izi zikutanthauza kuti mtundu wa lancet ndi \ (\ pafupifupi) 5 mm (chifukwa chakuti ndege ziwiri za lancet zimapanga mfundo imodzi29,30), bevel asymmetric ndi 7 mm, bevel asymmetric ndi 1. mm.Ma axisymmetric otsetsereka (pakati pa mphamvu yokoka amakhalabe osasinthasintha, kotero makulidwe a khoma la chitoliro okha amasintha motsetsereka).
Maphunziro a FEM ndi kugwiritsa ntchito ma equations pafupipafupi 29.75 kHz.(1) Powerengera kusiyanasiyana kwa mafunde opindika a theka (\(\lambda_y/2\)) kwa lancet (a), asymmetric (b) ndi axisymmetric (c) bevel geometries (monga mkuyu 1a,b,c) ).Mtengo wapakati \(\lambda_y/2\) wa lancet, asymmetric, ndi axisymmetric bevels anali 5.65, 5.17, ndi 7.52 mm, motsatana.Dziwani kuti makulidwe ansonga a ma asymmetric ndi axisymmetric bevel amangokhala \(\ pafupifupi) 50 µm.
Kuyenda pachimake \(|\tilde{Y}_{v_yF_y}|\) ndiko kuphatikiza koyenera kwa chubu kutalika (TL) ndi kutalika kwa bevel (BL) (Mkuyu 8, 9).Kwa lancet wamba, popeza kukula kwake kumakhazikika, TL yabwino kwambiri ndi \ (\ pafupifupi) 29.1 mm (mkuyu 8).Kwa ma asymmetric ndi axisymmetric bevels (mkuyu 9a, b, motsatana), maphunziro a FEM adaphatikizapo BL kuchokera ku 1 mpaka 7 mm, kotero kuti TL yabwino kwambiri inali kuchokera ku 26.9 mpaka 28.7 mm (kusiyana kwa 1.8 mm) ndi kuchokera ku 27.9 mpaka 29 .2 mm (zosiyanasiyana). 1.3 mm), motero.Pakuti asymmetric otsetsereka (mkuyu. 9a), ndi mulingo woyenera kwambiri TL chinawonjezeka linearly, anafika kumtunda pa BL 4 mm, ndiyeno chakuthwa utachepa kuchokera BL 5 kuti 7 mm.Kwa bevel axisymmetric (mkuyu 9b), TL yabwino kwambiri inakula motsatira ndi kuwonjezeka kwa BL ndipo potsiriza inakhazikika pa BL kuchokera ku 6 mpaka 7 mm.Kafukufuku wotalikirapo wa axisymmetric tilt (mkuyu 9c) adawulula ma TL abwino kwambiri pa \(\ pafupifupi) 35.1–37.1 mm.Kwa ma BL onse, mtunda pakati pa ma TL awiri abwino kwambiri ndi \(\ pafupifupi\) 8mm (wofanana ndi \(\lambda_y/2\)).
Kuyenda kwa Lancet ku 29.75 kHz.Singanoyo inali yosangalatsa kwambiri pamafupipafupi a 29.75 kHz ndipo kugwedezeka kunayesedwa pansonga ya singano ndikuwonetsa ngati kuchuluka kwa kayendedwe ka makina (dB poyerekeza ndi mtengo wapamwamba) kwa TL 26.5-29.5 mm (mu 0.1 mm increments) .
Maphunziro a parametric a FEM pafupipafupi a 29.75 kHz akuwonetsa kuti kusuntha kwa nsonga ya axisymmetric sikukhudzidwa kwambiri ndi kusintha kwa kutalika kwa chubu kuposa mnzake wa asymmetric.Bevel kutalika (BL) ndi chitoliro kutalika (TL) maphunziro asymmetric (a) ndi axisymmetric (b, c) bevel geometries mu kafukufuku ankalamulira pafupipafupi ntchito FEM (malire zinthu zikusonyezedwa mkuyu. 2).(a, b) TL idachokera ku 26.5 mpaka 29.5 mm (sitepe 0.1 mm) ndi BL 1-7 mm (sitepe 0.5 mm).(c) Maphunziro owonjezera a axisymmetric tilt kuphatikiza TL 25–40 mm (mu ma increments 0.05 mm) ndi BL 0.1–7 mm (mu ma increments a 0.1 mm) akusonyeza kuti \(\lambda_y/2\ ) ayenera kukwaniritsa zofunikira za nsonga.kusuntha malire a zinthu.
Kukonzekera kwa singano kumakhala ndi ma eigenfrequencies atatu \ (f_{1-3}\) ogawidwa m'madera otsika, apakati ndi apamwamba monga momwe tawonetsera mu Table 1. Kukula kwa PTE kunalembedwa monga momwe tawonetsera mkuyu.10 ndikuwunikidwa mumkuyu 11. Pansipa pali zopezeka pagawo lililonse la modali:
Chitsanzo chojambulira nthawi yomweyo mphamvu kutengerapo mphamvu (PTE) matalikidwe zopezedwa swept-pafupifupi sinusoidal chisangalalo kwa lancet (L) ndi axisymmetric bevel AX1-3 mu mpweya, madzi ndi gelatin akuya 20 mm.Mawonekedwe a mbali imodzi akuwonetsedwa.Kuyankha pafupipafupi (kuyesedwa pa 300 kHz) kudasefedwa pang'onopang'ono kenako kuchepetsedwa ndi gawo la 200 pakuwunika modali.Chiyerekezo cha sign-to-noise ndi \(\le\) 45 dB.Magawo a PTE (mizere yofiirira yamadontho) amawonetsedwa mu madigiri (\(^{\circ}\)).
Kusanthula kwa mayankho a modal (kumatanthauza ± kupatuka kokhazikika, n = 5) komwe kukuwonetsedwa mkuyu. otsika, apakati ndi okwera) ndi ma frequency ofananirako\(f_{1-3 }\) (kHz), (avareji) amphamvu \(\mawu {PTE}_{1{-}3}\) Owerengedwa pogwiritsa ntchito zofanana .(4) ndi (pansi) m’lifupi mwake ndi theka la miyeso yokwanira \(\mawu {FWHM}_{1{-}3}\) (Hz), motsatana.Dziwani kuti muyeso wa bandwidth adalumphira pamene PTE yotsika idalembetsedwa, mwachitsanzo \(\mawu {FWHM}_{1}\) ngati atsetsereka AX2.Mawonekedwe a \ (f_2\) adapezeka kuti ndiwoyenera kwambiri kufananiza zokhotakhota zotsetsereka, popeza zidawonetsa kuchuluka kwamphamvu kosinthira mphamvu (\(\text {PTE}_{2}\)), mpaka 99%.
Dera loyamba la modal: \ (f_1\) sizidalira kwambiri mtundu wa sing'anga yomwe yayikidwa, koma zimatengera geometry ya malo otsetsereka.\ (f_1\) imachepa ndi kuchepa kwa kutalika kwa bevel (27.1, 26.2 ndi 25.9 kHz mumlengalenga kwa AX1-3, motsatana).Miyezo yachigawo \(\mawu {PTE}_{1}\) ndi \(\mawu {FWHM}_{1}\) ndi \(\approx\) 81% ndi 230 Hz motsatana.\(\text {FWHM}_{1}\) ili ndi gelatin yapamwamba kwambiri mu Lancet (L, 473 Hz).Dziwani kuti \(\text {FWHM}_{1}\) AX2 mu gelatin sinayesedwe chifukwa cha matalikidwe otsika a FRF.
Dera lachiwiri la modal: \(f_2\) zimatengera mtundu wa media womwe wayikidwa ndi bevel.Avereji yamtengo \(f_2\) ndi 29.1, 27.9 ndi 28.5 kHz mumpweya, m'madzi ndi gelatin, motsatana.Dera la modalli linawonetsanso PTE yapamwamba ya 99%, yapamwamba kwambiri kuposa gulu lililonse loyezedwa, ndi pafupifupi 84%.\(\text {FWHM}_{2}\) ili ndi avereji yachigawo ya \(\ pafupifupi\) 910 Hz.
Dera lachitatu: pafupipafupi \(f_3\) zimatengera mtundu wa media ndi bevel.Avereji ya \(f_3\) ndi 32.0, 31.0 ndi 31.3 kHz mumpweya, m'madzi ndi gelatin, motsatana.Chiwerengero cha \(\text {PTE}_{3}\) chinali \(\pafupifupi\) 74%, chotsikitsitsa kuposa chigawo chilichonse.Avereji yachigawo \(\mawu {FWHM}_{3}\) ndi \(\pafupifupi\) 1085 Hz, omwe ndi apamwamba kuposa chigawo choyamba ndi chachiwiri.
Zotsatirazi zikunena za mkuyu.12 ndi Table 2. Lancet (L) inapotoza kwambiri (ndi kufunikira kwakukulu kwa nsonga zonse, \ (p<\) 0.017) mumlengalenga ndi madzi (mkuyu 12a), kukwaniritsa DPR yapamwamba (mpaka 220 µm / W mu mlengalenga). 12 ndi Table 2. Lancet (L) inapotoza kwambiri (ndi kufunikira kwakukulu kwa nsonga zonse, \ (p<\) 0.017) mumlengalenga ndi madzi (mkuyu 12a), kukwaniritsa DPR yapamwamba (mpaka 220 µm / W mu mlengalenga). Следующее относится к рисунку 12 ndi таблице 2. Ланцет (L) отклонялся больше всего (с высокой значимостью для , 7, 7) воздухе, так и в воде (рис. 12а), достигая самого высокого DPR . Zotsatirazi zikugwiritsidwa ntchito ku Chithunzi 12 ndi Table 2. Lancet (L) inasokoneza kwambiri (ndi kufunikira kwakukulu kwa nsonga zonse, \ (p <\) 0.017) mumlengalenga ndi madzi (mkuyu 12a), kukwaniritsa DPR yapamwamba kwambiri.(mpaka 220 μm/W mumlengalenga).Smt.Chithunzi 12 ndi Gulu 2 pansipa.柳叶刀(L) 在空气和水中偏转最多(对所有尖端具有高显着性,\(p<\) 0.017(图端具)(图端具)(图端具)高达220 µm/W)柳叶刀(L) ili ndi kutembenuka kwapamwamba kwambiri mumlengalenga ndi m'madzi (对所记尖端可以高电影性,\(p<\) 0.017) (图12a), ndipo adapeza DPR yapamwamba kwambiri (mpaka 220 µm/W mkati mpweya). Ланцет (L) отклонялся больше всего (высокая значимость для всех наконечников, (p<\) 0,017) в воздухе и воде (риадо 12). 20 мкм/Вт в воздухе). Lancet (L) inasokoneza kwambiri (kufunika kwakukulu kwa nsonga zonse, \ (p <\) 0.017) mumlengalenga ndi madzi (mkuyu 12a), kufika ku DPR yapamwamba kwambiri (mpaka 220 µm / W mumlengalenga). Mumlengalenga, AX1 yomwe inali ndi BL yapamwamba, inapatuka kuposa AX2–3 (ndi tanthauzo, \(p<\) 0.017), pomwe AX3 (yomwe inali ndi BL yotsika kwambiri) idapatuka kuposa AX2 ndi DPR ya 190 µm/W. Mumlengalenga, AX1 yomwe inali ndi BL yapamwamba, inapatuka kuposa AX2–3 (ndi tanthauzo, \(p<\) 0.017), pomwe AX3 (yomwe inali ndi BL yotsika kwambiri) idapatuka kuposa AX2 ndi DPR ya 190 µm/W. В воздухе AX1 с более высоким BL отклонялся выше, чем AX2–3 (со значимостью \(p<\) 0,017), тогда как AX3 (с самлон , зким BLня ни). X2 pa DPR 190 мкм/Вт. Mumlengalenga, AX1 yokhala ndi BL yokwera kwambiri idapatuka kuposa AX2–3 (ndi tanthauzo \(p<\) 0.017), pomwe AX3 (yotsika kwambiri BL) idapatuka kuposa AX2 ndi DPR 190 μm/W.在空气中,具有更高BL的AX1 比AX2-3 偏转更高(具有显着性,\(p<\) 0.017),而AX3(具有显着性),而AX3(具有显着性) 190µm/W . M'mlengalenga, kupatuka kwa AX1 yokhala ndi BL yapamwamba ndikwapamwamba kuposa kwa AX2-3 (mofunikira, \(p<\) 0.017), ndipo kupatuka kwa AX3 (ndi BL yotsika kwambiri) ndikokulirapo kuposa kwa AX2, DPR ndi 190. µm/W . В воздухе AX1 с более высоким BL отклоняется больше, чем AX2-3 (значимо, \(p<\) 0,017), тогда как AX3 (с самым больше, AX2-3) 2 с DPR 190 мкм/Вт. Mumlengalenga, AX1 yokhala ndi BL yapamwamba imapatuka kuposa AX2-3 (yofunikira, \(p<\) 0.017), pomwe AX3 (yokhala ndi BL yotsika kwambiri) imapatuka kupitilira AX2 ndi DPR 190 µm/W.Pamadzi a 20 mm, kupotoza ndi PTE AX1-3 sizinali zosiyana kwambiri (\(p>\) 0.017).Miyezo ya PTE m'madzi (90.2-98.4%) nthawi zambiri inali yapamwamba kuposa mpweya (56-77.5%) (mkuyu 12c), ndipo chodabwitsa cha cavitation chinadziwika panthawi yoyesera m'madzi (mkuyu 13, onaninso zowonjezera). chidziwitso).
Kuchuluka kwa nsonga yopatuka (kutanthauza ± SD, n = 5) kuyeza kwa bevel L ndi AX1-3 mumlengalenga ndi m'madzi (kuya 20 mm) kukuwonetsa kusintha kwa geometry ya bevel.Miyezoyi idapezedwa pogwiritsa ntchito mayendedwe amtundu wa sinusoidal mosalekeza.(a) Kupatuka kwapamwamba kwambiri (\(u_y\vec {j}\)) pansonga, kuyezedwa pa (b) ma frequency awo \ (f_2\).(c) Kugwiritsa ntchito mphamvu (PTE, RMS, %) ya equation.(4) ndi (d) Deflection power factor (DPR, µm/W) yowerengedwa ngati kupatuka pachimake-kupita pachimake ndi mphamvu yamagetsi yopatsirana \(P_T\) (Wrms).
Chithunzi chowoneka bwino chazithunzi za kamera yothamanga kwambiri chomwe chikuwonetsa kupatuka kwapakatikati (mizere yobiriwira ndi madontho ofiira) ya lancet (L) ndi nsonga ya axisymmetric (AX1-3) m'madzi (kuzama 20 mm) kupitilira theka la kuzungulira.cycle, pa excitation frequency \ (f_2 \) (sampling frequency 310 kHz).Chithunzi chojambulidwa cha grayscale chili ndi kukula kwa ma pixel 128×128 ndi kukula kwa pixel kwa \(\ approx\) 5 µm.Kanema angapezeke mu zina zambiri.
Choncho, ife anatengera kusintha mapindikidwe wavelength (mkuyu. 7) ndi kuwerengetsa transferable makina kuyenda kwa osakaniza chitoliro kutalika ndi chamfer (mkuyu. 8, 9) kwa ochiritsira Lancet, asymmetric ndi axisymmetric chamfers wa akalumikidzidwa geometric.Kutengera zotsirizirazi, tidayerekeza mtunda woyenera wa 43 mm (kapena \(\ pafupifupi) 2.75\(\lambda _y\) pa 29.75 kHz) kuchokera kunsonga kupita ku weld, monga tawonera mkuyu 5, ndikupanga Three axisymmetric. ma bevel okhala ndi utali wosiyanasiyana wa bevel.Kenako tidawonetsa machitidwe awo pafupipafupi mumlengalenga, m'madzi, ndi 10% (w/v) ballistic gelatin poyerekeza ndi ma lancets wamba (Zithunzi 10, 11) ndikusankha njira yoyenera kwambiri yofananira ndi bevel.Pomaliza, tinayesa kupotokola kwa nsonga mwa kupinda mafunde mumlengalenga ndi m'madzi akuya mamilimita 20 ndikuwerengera mphamvu yotumizira mphamvu (PTE, %) ndi deflection power factor (DPR, µm/W) ya sing'anga yoyikapo pa bevu iliyonse.mtundu wa angular (mkuyu 12).
Needle bevel geometry yawonetsedwa kuti imakhudza kuchuluka kwa nsonga ya singano.Lancet inapindula kwambiri komanso DPR yapamwamba kwambiri poyerekeza ndi axisymmetric bevel yokhala ndi kuchepa kwapakati (mkuyu 12).Bevel ya 4 mm axisymmetric bevel (AX1) yokhala ndi bevu yayitali kwambiri idakwanitsa kupotokola kwambiri mumlengalenga poyerekeza ndi singano zina za axisymmetric (AX2-3) (\(p <0.017\), Gulu 2), koma panalibe kusiyana kwakukulu. .zimawonedwa pamene singano yayikidwa m'madzi.Chifukwa chake, palibe phindu lodziwikiratu kukhala ndi kutalika kwa bevel motalikirapo pakupatuka pachimake pansonga.Poganizira izi, zikuwoneka kuti geometry ya bevel yophunziridwa mu phunziroli ili ndi chikoka chachikulu pa kuchuluka kwa kupatuka kuposa kutalika kwa bevel.Izi zitha kukhala chifukwa cha kuuma kopindika, mwachitsanzo kutengera makulidwe onse azinthu zomwe zikupindika komanso kapangidwe ka singano.
M'maphunziro oyesera, kukula kwa mawonekedwe a flexural wave kumakhudzidwa ndi malire a nsonga.Pamene nsonga ya singano ilowetsedwa m'madzi ndi gelatin, \(\mawu {PTE}_{2}\) ndi \(\ pafupifupi\) 95%, ndipo \(\text {PTE}_{2}\) ndi \ (\text {PTE}_{2}\) mtengo ndi 73% ndi 77% ya (\text {PTE}_{1}\) ndi \(\text {PTE}_{3}\), motsatira (mkuyu 11).Izi zikuwonetsa kuti kusamutsidwa kwakukulu kwa mphamvu yamayimbidwe kupita ku sing'anga, mwachitsanzo, madzi kapena gelatin, kumachitika pa \(f_2\).Khalidwe lofananalo lidawonedwa mu phunziro lapitalo31 pogwiritsa ntchito kasinthidwe kachipangizo kachipangizo kakang'ono ka 41-43 kHz pafupipafupi, pomwe olemba adawonetsa kudalira kwamagetsi owonetsera magetsi pamakina amakina apakati.Kuzama kolowera32 ndi mawonekedwe amakanikidwe a minofuyo amapereka katundu wamakina pa singano motero akuyembekezeka kukhudza machitidwe a UZEFNAB.Chifukwa chake, ma aligorivimu a resonance (mwachitsanzo 17, 18, 33) angagwiritsidwe ntchito kukhathamiritsa mphamvu yamayimbidwe yoperekedwa kudzera mu singano.
Kuyerekezera pa kupindika kwa mafunde (mkuyu 7) kumasonyeza kuti nsonga ya axisymmetric imakhala yolimba kwambiri (ie, yolimba kwambiri popinda) kuposa lancet ndi asymmetric bevel.Kutengera (1) ndikugwiritsa ntchito ubale wodziwika wa liwiro la pafupipafupi, timayerekeza kuuma kopindika kunsonga kwa singano monga \ (\ pafupifupi \) 200, 20 ndi 1500 MPa ya lancet, asymmetric ndi axial opendekera ndege, motsatana.Izi zikufanana ndi \ (\ lambda_y\) ya \ (\ pafupifupi\) 5.3, 1.7, ndi 14.2 mm, motero, pa 29.75 kHz (Mkuyu 7a–c).Poganizira zachitetezo chachipatala pa USeFNAB, zotsatira za geometry pakuuma kwamapangidwe a ndege yolunjika ziyenera kuyesedwa34.
Kafukufuku wa magawo a bevel okhudzana ndi kutalika kwa chubu (mkuyu. 9) adawonetsa kuti njira yabwino kwambiri yopatsirana inali yapamwamba kwa bevel asymmetric (1.8 mm) kuposa bevel axisymmetric (1.3 mm).Kuonjezera apo, kuyenda kumakhala kokhazikika pa \ (\ pafupifupi) kuchokera ku 4 mpaka 4.5 mm ndi kuchokera ku 6 mpaka 7 mm kwa asymmetric ndi axisymmetric tilts, motero (Mkuyu 9a, b).Kufunika kothandiza kwa kupezedwaku kumawonetsedwa pakulolera kwa kupanga, mwachitsanzo, kutsika kwapang'onopang'ono kwa TL koyenera kungatanthauze kuti kulondola kwautali kumafunika.Panthawi imodzimodziyo, mapiri oyendayenda amapereka kulekerera kwakukulu posankha kutalika kwa kuviika pafupipafupi popanda kukhudzidwa kwakukulu pakuyenda.
Phunziroli likuphatikizapo zolephera zotsatirazi.Kuyeza kwachindunji kwa kupatuka kwa singano pogwiritsa ntchito kuzindikira m'mphepete ndi kujambula mothamanga kwambiri (Chithunzi 12) kumatanthauza kuti timangokhala ndi zinthu zowonekera bwino monga mpweya ndi madzi.Tikufunanso kunena kuti sitinagwiritse ntchito zoyesera kuyesa kusuntha kofananira komanso mosiyana, koma tinagwiritsa ntchito maphunziro a FEM kuti tidziwe kutalika kokwanira kwa singano.Pankhani ya zolephera zothandiza, kutalika kwa lancet kuchokera kunsonga kupita kumanja ndi \ (\ pafupifupi) 0.4 cm kutalika kuposa singano zina (AX1-3), onani mkuyu.3b .Izi zitha kukhudza kuyankha kwa modal kwa kapangidwe ka singano.Kuonjezera apo, mawonekedwe ndi kuchuluka kwa solder kumapeto kwa pini ya waveguide (onani Chithunzi 3) zingakhudze kuwonongeka kwa makina a kamangidwe ka pini, kuyambitsa zolakwika muzowonongeka zamakina ndi khalidwe lopindika.
Pomaliza, tawonetsa kuti kuyesa kwa bevel geometry kumakhudza kuchuluka kwa zolakwika mu USeFNAB.Ngati kupatukana kwakukulu kungakhale ndi zotsatira zabwino pa zotsatira za singano pa minofu, monga kudula bwino pambuyo pa kuboola, ndiye kuti lancet wamba ikhoza kulangizidwa ku USeFNAB chifukwa imapereka kupatuka kwakukulu ndikusunga kuuma kokwanira kwa nsonga yamapangidwe..Kuphatikiza apo, kafukufuku waposachedwa35 wawonetsa kuti kupotoza kwambiri nsonga kumatha kupititsa patsogolo zotsatira zachilengedwe monga cavitation, zomwe zingathandize kupanga maopaleshoni ochepa kwambiri.Poganizira kuti kuwonjezereka kwamphamvu kwamayimbidwe akuwonetsa kuchulukitsa kuchuluka kwa ma biopsies mu USeFNAB13, maphunziro owonjezera a kuchuluka kwa zitsanzo ndi mtundu wake amafunikira kuti awone zatsatanetsatane zazachipatala za geometry ya singano yophunziridwa.
Nthawi yotumiza: Apr-24-2023