An analogical study of wave equations,physical quantities,conservation and reciprocity equations between electromagnetic and elastic waves

This paper presents an analogical study between electromagnetic and elastic wave fields,with a one-to-one correspondence principle established regarding the basic wave equations,the physical quantities and the differential operations.Using the electromagnetic-to-elastic substitution,the analogous relations of the conservation laws of energy and momentum are investigated between these two physical fields.Moreover,the energy-based and momentum-based reciprocity theorems for an elastic wave are also derived in the time-harmonic state,which describe the interaction between two elastic wave systems from the perspectives of energy and momentum,respectively.The theoretical results obtained in this analysis can not only improve our understanding of the similarities of these two linear systems,but also find potential applications in relevant fields such as medical imaging,non-destructive evaluation,acoustic microscopy,seismology and exploratory geophysics.

Nonreciprocal Photon Blockade Based on Zeeman Splittings Induced by a Fictitious Magnetic Field

Quantum nonreciprocity, such as nonreciprocal photon blockade, has attracted a great deal of attention due to its unique applications in quantum information processing. Its implementation primarily relies on rotating nonlinear systems, based on the Sagnac effect. Here, we propose an all-optical approach to achieve nonreciprocal photon blockade in an on-chip microring resonator coupled to a V-type Rb atom, which arises from the Zeeman splittings of the atomic hyperfine sublevels induced by the fictitious magnetic field of a circularly polarized control laser. The system manifests single-photon blockade or multi-photon tunneling when driven from opposite directions. This nonreciprocity results from the directional detunings between the countercirculating probe fields and the V-type atom, which does not require the mechanical rotation and facilitates integration. Our work opens up a new route to achieve on-chip integrable quantum nonreciprocity, enabling applications in chiral quantum technologies.

Magnetic Nonreciprocity in a Hybrid Device of Asymmetric Artificial Spin-Ice-Superconductors

Controlling the size and distribution of potential barriers within a medium of interacting particles can unveil unique collective behaviors and innovative functionalities.We introduce a unique superconducting hybrid device using a novel artificial spin ice structure composed of asymmetric nanomagnets.This structure forms a distinctive superconducting pinning potential that steers unconventional motion of superconducting vortices,thereby inducing a magnetic nonreciprocal effect,in contrast to the electric nonreciprocal effect commonly observed in superconducting diodes.Furthermore,the polarity of the magnetic nonreciprocity is in situ reversible through the tunable magnetic patterns of artificial spin ice.Our findings demonstrate that artificial spin ice not only precisely modulates superconducting characteristics but also opens the door to novel functionalities,offering a groundbreaking paradigm for superconducting electronics.

Bidirectional rotating direct-current triboelectric nanogenerator with self-adaptive mechanical switching for harvesting reciprocating motion

Amid the growing interest in triboelectric nanogenerators(TENGs)as novel energy-harvesting devices,several studies have focused on direct current(DC)TENGs to generate a stable DC output for operating electronic devices.However,owing to the working mechanisms of conventional DC TENGs,generating a stable DC output from reciprocating motion remains a challenge.Accordingly,we propose a bidirectional rotating DC TENG(BiR-TENG),which can generate DC outputs,regardless of the direction of rotation,from reciprocating motions.The distinct design of the BiR-TENG enables the mechanical rectification of the alternating current output into a rotational-direction-dependent DC output.Furthermore,it allows the conversion of the rotational-direction-dependent DC output into a unidirectional DC output by adapting the configurations depending on the rotational direction.Owing to these tailored design strategies and subsequent optimizations,the BiR-TENG could generate an effective unidirectional DC output.Applications of the BiR-TENG for the reciprocating motions of swinging doors and waves were demonstrated by harnessing this output.This study demonstrates the potential of the BiR-TENG design strategy as an effective and versatile solution for energy harvesting from reciprocating motions,highlighting the suitability of DC outputs as an energy source for electronic devices.

Optimal interval for delayed retrieval surgery with reciprocating morcellators after enucleation of giant prostatic hyperplasia in holmium laser enucleation of the prostate

Objective:The aim of this research was to evaluate the efficiency of reciprocating morcellation for removing giant benign prostatic hyperplasia during holmium laser enucleation of the prostate,investigate whether performing morcellation as a two-stage procedure improves tissue retrieval efficiency,and seek to determine the optimal interval between the two surgeries.Methods:This study included nine cases of holmium laser enucleation of the prostate with an enucleated prostate weight exceeding 200 g,indicative of substantial prostate enlargement.Morcellation was performed on Day 0(n=4),Day 4(n=1),Day 6(n=1),and Day 7(n=3).The intervals were compared regarding the morcellation efficiency,beach ball presence,and pathology.Results:The mean estimated prostate volume was 383(range 330e528)mL;the median enucleation weight was 252(interquartile range[IQR]222,342)g;and the median enucleation time was 83(IQR 62,100)min.The mean morcellation efficiency was 1.44(SD 0.55)g/min on Day 0 and 13.69(SD 2.46)g/min on day 7.The morcellation efficiency was 4.15 g/min and 10.50 g/min on Day 4 and Day 6,respectively,with significantly higher in the two-stage group compared to one-stage group(11.0 g/min vs.1.5 g/min;p=0.014).Efficiency was strongly correlated with intervals(p<0.001);the incidences of beach balls were 100%(4/4)and 60%(3/5)in the immediate and two-stage surgery groups,respectively.Conclusion:The efficiency of two-stage morcellation with reciprocating morcellators was highly related to the postoperative interval,with the maximum efficiency reached on Day 7.

Reciprocal Distance Laplacian Eigenvalue Distribution Based on Graph Parameters

Let G be a connected graph of order n and m_(RD)^(L)_(G)I denote the number of reciprocal distance Laplacian eigenvaluesof G in an interval I.For a given interval I,we mainly present several bounds on m_(RD)^(L)_(G)I in terms of various structuralparameters of the graph G,including vertex-connectivity,independence number and pendant vertices.

Reciprocity Relation between Alternative Gravity Formulas

We compare Newton’s force law of universal gravitation with a corrected simple approach based on Bhandari’s recently presented work, where the gravitation constant G is maintained. A reciprocity relation exists between both alternative gravity formulas with respect to the distances between mass centers. We conclude a one-to-one mapping of the two gravitational formulas. We don’t need Einstein’s construct of spacetime bending by matter.

Low temperature quasi-superplasticity of ZK60 alloy prepared by reciprocating extrusion

Fine-grained ZK60 alloy was prepared by 2-pass reciprocating extrusion, and the low temperature superplasticity was conducted in a temperature range from 443 to 523 K and an initial strain rate ranging from 3.3×10^-4 to 3.3×10-2^s^-1. The results show that the alloy has an equiaxed grain structure with an average grain size of about 5.0μm, and the sizes of broken secondary particles and precipitates are no more than 175 and 50 nm, respectively. The alloy exhibits quasi-superplasticity with a maximum elongation of 270% at 523 K and an initial strain rate of 3.3×10^-4 s^-1. The strain rate sensitivity m is less than 0.2 at 443 and 473 K, and it is 0.42 at 523 K. The apparent activation energies at temperature below 473 K and at 523 K are less than 63.2 and 110.6 kJ/mol, respectively At temperature below 473 K, mainly intragranular sliding contributes to superplastic flow. At 523 K, grain boundary sliding is the dominant deformation mechanism, and dislocation creep controlled by grain boundary diffusion is considered to be the main accommodation mechanism.

机用ProTaper和Reciproc对弯曲根管成形能力的对比研究

目的:比较机用Pro Taper(PT)和Reciproc(RE)两种镍钛根管预备系统对弯曲根管的成形能力。方法:选择20个离体下颌第一磨牙,随机分为2组(n=10),分别用PT和RE进行根管预备并记录预备时间;在根管预备前后分别进行Micro-CT扫描,并利用Fitme DICOM Viewer软件进行根管三维重建和分析,比较2种器械对弯曲根管的形能力。结果:三维重建图像显示,根管预备前后弯曲度的改变量PT组大于RE组(P<0.05);两组根管体积和表面积的改变量在根上部和根中部差异无统计学意义(P>0.05),而在根尖部PT组大于RE组(P<0.05);根管预备时间PT组长于RE组(P<0.05)。结论:单支锉根管预备系统Reciproc在预备效率及中心定位能力,尤其在根尖1/3部,优于机用Pro Taper。

TFA、Reciproc及ProTaper Next根管预备系统的清洁能力及根尖推出物量的比较

目的:评价3种新型镍钛根管预备系统TFA、Reciproc及ProTaper Next的根管清洁能力及根尖推出量的差异。方法:将40个人类单根管前磨牙随机分为4组(n=10),分别用K锉(A组)、TFA(B组)、Reciproc(C组)和ProTaper Next(D组)进行根管预备后,用扫描电镜(SEM)对各组根管壁表面的碎屑及玷污层进行评估。然后再将40个树脂根管模型随机分为4组(n=10),分别采用上述4种预备系统进行根管预备,在预备过程中收集其根尖推出物,分别称量,用Ahmad评估标准比较各组推出碎屑及冲洗液的量。结果:各组根管壁的碎屑及玷污层评分由高到低依次为:A组>D组>C组>B组(组间两两相比P<0.05);各组推出根尖的碎屑及冲洗液的量由高到低依次为:K锉组>Reciproc组>ProTaper Next组>TFA组(组间两两相比P<0.05)。结论:TFA、Reciproc及ProTaper Next 3种镍钛预备系统的根管清洁力均优于K锉,TFA效果最佳。

Reciproc单支锉预备磨牙弯曲根管疗效观察

目的：评价往复运动式Reciproc单支锉预备磨牙弯曲根管，保持原根管解剖走向的能力。方法选择年龄18～59岁牙髓病初诊病例，按 Schneider 测量法，第一磨牙弯曲根管（20°～30°）100例，200个根管（颊，舌弯曲根管），随机分为Reciproc组50例，100个根管，Protaper组50例，100个根管，进行根管预备。测量术前片、插针片、主尖片的根管弯曲度，比较根管偏移率，评价根管成形和根尖封闭效果。结果2组机用镍钛锉备根成功率：Reciproc组99％，Protaper组92％，有显著性差异（ P＜0．05）。结论 Reciproc的创新设计，使预备磨牙弯曲根管成形佳，反应轻，根尖封闭好，快捷高效，实现了一支锉代替一组锉。

Protaper next和Reciproc在一次法根管治疗术中的应用效果比较

目的:探讨比较Protaper next和Reciproc在一次法根管治疗术中的应用效果。方法:将我院2017年11月-2018年11月接收的90例行一次法根管治疗的病人随机均分为PTN组(采用Protaper next根管预备系统)与RP组(采用Reciproc根管预备系统),比较二组的根管预备时间、疼痛率及有效率。结果:PTN组每个根管的平均预备时间显著长于RP组(P<0.05);根管治疗1周后,PTN组的疼痛率显著低于RP组(P<0.05);二组治疗总有效率比较差异无统计学意义(P>0.05)。结论:Protaper next及Reciproc根管预备系统疗效相当,但Reciproc的根管预备用时较短,Protaper next的术后疼痛发生率较低。

Reciproc和Mtwo两种镍钛根管预备系统在下颌第一磨牙一次法根管治疗术中的应用对比

目的评价应用Reciproc和Mtwo两种镍钛根管预备系统在下颌第一磨牙一次法根管治疗术中的效果差异。方法选择2015年6月~2016年6月在我院行下颌第一磨牙一次法根管治疗术的72例患者,随机分为R组和M组,各组36例分别在基础治疗之上采用Reciproc和Mtwo两种镍钛根管预备系统进行根管预备后行根管填充,术后随访6个月,比较两组患者根管预备时间、根管预备并发症(如髓腔穿孔、台阶和器械折断)、根管填充情况和根管治疗约诊间痛(EIAP)以及术后6个月的疗效差异。结果 R组和M组的根管准备时间分别为(120.23±38.67)s和(72.82±36.22)s,R组的EIAP发生率和疼痛程度明显低于M组,差异有统计学意义(P<0.05)两组根管预备并发症发生率、根管恰填率、以及术后6个月的疗效均无统计学差异(P>0.05)。结论与Mtwo镍钛;根管预备系统相比,在下颌第一磨牙一次法根管治疗术中应用Reciproc镍钛根管预备系统的根管准备时间较短,患者疼痛反应较小,而临床疗效无统计学差异,值得推广。

VDW Reciproc Blue单支锉与传统根管治疗器械在牙髓炎治疗中的疗效对比

目的对比VDW Reciproc Blue单支锉与传统根管治疗器械在牙髓炎治疗中的疗效。方法将60例牙髓炎患者随机分为对照组与实验组,每组30例。对照组采用传统根管预备器械,实验组采用VDW Reciproc Blue单支锉,比较两组的根管预备成型效果(根管流畅度)、根管填充效果、Negm分级(疼痛状态分级)、器械折断率及根管预备时间。结果实验组根管流畅度与根管填充效果均优于对照组(P<0.05);Negm分级轻于对照组(P<0.05)。实验组根管预备时间短于对照组(P<0.01)。结论VDW Reciproc Blue单支锉能够减少患者椅旁时间、减轻术后疼痛和提高治疗效果。

Reciprocity as an Ever-Present Dual Property of Everything

Reciprocity may be understood as relation of action and reaction in the sense of Hegel’s philosophical definition. Quoting Kant, freedom and ethical necessities are reciprocally limited. In this contribution, a more mathematical than philosophical reflection about reciprocity as an ever-present dual property of everything was given. As a crystallographer, the author is familiar with the action of Fourier transforms and the relation between a crystal lattice and its reciprocal lattice, already pointing to the duality between particles and waves. A generalization of the reciprocity term was stimulated by results of the famous Information Relativity (IR) theory of Suleiman with its proven physical manifestation of matter-wave duality, compared to the set-theoretical E-Infinity theory developed by El Naschie, where the zero set represents the pre-quantum particle, and the pre-quantum wave is assigned to the empty set boundary surrounding the pre-particle. Expectedly, the most irrational number of the golden mean is involved in these thoughts, because this number is intimately connected with its inverse. An important role plays further Hardy’s maximum quantum entanglement probability as the fifth power of &phi;and its connection to the dark matter. Remembering, the eleven dimensions in Witten’s M-theory may be decomposed into the Lucas number L5 = 11 = &phi;&minus;5 – &phi;5. Reciprocity is indeed omnipresent in our world as piloting waves that accompany all observable earthen and cosmic matter. As a side effect of the IR theory some fundamental constants such as the gyromagnetic factor of the electron, Sommerfeld’s fine-structure constant as well as the charge of the electron must be marginally changed caused by altered relativistic corrections. Consequences also arise for our vision about the evolution of life and consciousness.

Rayleigh reciprocity relations： Applications

Classical reciprocity relations have wide applications in acoustics, from field representation to generalized optical theorem. In this paper we introduce our recent results on the applications and generalization of classical Rayleigh reciprocity relation： higher derivative reciprocity relations as a generalization of the classical one and a theoretical proof on the Green＇s function retrieval from volume noises.

GENERALIZED RECIPROCAL THEOREMS AND THEIR APPLICATIONS

Generalized reciprocal theorems of non-coupled and coupled systems, which are valid for two deformed bodies with different constitutive relations are established by generalizing the idea of Betti's reciprocal theorem. When the constitutive relations of the two deformed bodies are all alike and linear elastic the generalized reciprocal theorem of non-coupled systems just becomes Betti's. Meanwhile the generalized reciprocal theorems are applied to simulate calculations in elasticity.

Investigation on Feeding Back Current Reciprocal Oscillographic Chronopotentiometric New Techniques

Reciprocal oscillographic chronopotentiogram is such a curve that can converts incisions on "(dE/dt)-E" oscillogram into peaks on "(dt/dE)-E" curve. In order to increase the sensitivity, a new technique called feeding back current was added in new circuit of obtaining reciprocal oscillgraphic chronopotentiogram. It can make capacity current be subtracted easily. Using this method, we carry out studying on principle and titration of drug.

Reciproc单支锉清除iRoot SP糊剂单尖法根管充填材料的再治疗效率研究

目的以AH糊剂冷侧压法、热牙胶垂直加压法为对照,口腔锥形束CT(CBCT)三维重建评价使用Reciproc单支锉去除iRoot SP糊剂单尖法术后根管充填材料的再治疗效率。方法选择福建医科大学附属福州市第一医院口腔科2021年7—11月正畸拔除的卵圆形单根管下颌前磨牙90个,采用随机数表法分为iRoot SP糊剂单尖法组(1组)、热牙胶垂直加压组(2组)和AH糊剂冷侧压组(3组)。使用Reciproc单支锉再治疗,终末超声荡洗2 min。分别于根充术后、再治疗、超声荡洗后CBCT扫描并三维重建,记录再治疗时间、根管残余充填材料体积。结果1组再治疗耗时最长,2组最短,差异有统计学意义(P<0.05)。1组残余充填材料最多,大于2组,差异有统计学意义(P<0.05),大于3组,但差异无统计学意义(P>0.05)。超声荡洗后,1组残余量大幅度减少,差异有统计学意义(P<0.05);最终残余量大于2组,差异有统计学意义(P<0.05),大于3组,但差异无统计学意义(P>0.05)。结论无论哪种充填方法,Reciproc单支锉再治疗均不能完全去除充填材料。iRoot SP糊剂单尖法进行再治疗耗时最多,残余量也最多,超声荡洗能够显著减少残余量。

Fluid-solid Interaction Model for Hydraulic Reciprocating O-ring Seals

Elastohydrodynamic lubrication characteristics of hydraulic reciprocating seals have significant effects on sealing and tribology performances of hydraulic actuators, especially in high parameter hydraulic systems. Only elastic deformations of hydraulic reciprocating seals were discussed, and hydrodynamic effects were neglected in many studies. The physical process of the fluid-solid interaction effect did not be clearly presented in the existing fluid-solid interaction models for hydraulic reciprocating O-ring seals, and few of these models had been simultaneously validated through experiments. By exploring the physical process of the fluid-solid interaction effect of the hydraulic reciprocating O-ring seal, a numerical fluid-solid interaction model consisting of fluid lubrication, contact mechanics, asperity contact and elastic deformation analyses is constructed with an iterative procedure. With the SRV friction and wear tester, the experiments are performed to investigate the elastohydrodynamic lubrication characteristics of the O-ring seal. The regularity of the friction coefficient varying with the speed of reciprocating motion is obtained in the mixed lubrication condition. The experimental result is used to validate the fluid-solid interaction model. Based on the model, The elastohydrodynamic lubrication characteristics of the hydraulic reciprocating O-ring seal are presented respectively in the dry friction, mixed lubrication and full film lubrication conditions, including of the contact pressure, film thickness, friction coefficient, liquid film pressure and viscous shear stress in the sealing zone. The proposed numerical fluid-solid interaction model can be effectively used to analyze the operation characteristics of the hydraulic reciprocating O-ring seal, and can also be widely used to study other hydraulic reciprocating seals.