柔性电极的丝网印刷工艺研究

柔性电极是实现对人体组织长期稳定界面监测及后端人机交互的核心部件,在疾病诊断、疾病治疗康复、运动监测等柔性人机接口应用场景中发挥着至关重要的作用。柔性电极因其穿戴便捷、可拉伸性好、皮肤界面稳定等优势,为生物电传感技术带来了革命性的变化。本文通过调整丝网印刷工艺,优选印刷压力、压印角和网距,有效降低了柔性电极的方阻,提升了丝网印刷质量和监测设备信号传输质量。

硅丙乳液的制备及工艺研究

本文主要介绍了硅丙乳液的制备过程,并对工艺参数及其对乳液性能的影响进行了讨论,可制备出低凝胶率、低单体残留率、不同粒径及粘度的硅丙乳液。随着新材料的不断开发和现有实验方法的不断改进,硅丙乳液性能愈加优异,随之,该系列产品作为粘合剂时,在新能源领域越来越受到青睐,其性能优势与锂离子电池的特殊要求有较高的契合点,尤其在锂离子电池电极材料中有望得以应用。

硅碳负极材料及其粘合剂研究进展

硅碳复合材料是锂离子电池负极未来发展的重要方向,其制备的硅碳负极是有助于实现高容量、高续航能力的重要新型负极材料,而用于硅碳负极的高性能粘合剂也是锂离子电池研究的一大热点。本文概述了硅碳负极材料的制备方法及其分类,总结了目前硅碳负极粘合剂类型、制备方法以及对锂电池电性能的影响。

Partial Surface Damper to Suppress Vibration for Thin Walled Plate Milling

The material removal rate and required work- piece surface quality of thin-walled structure milling are greatly limited due to its severe vibration, which is directly associated with the dynamic characteristics of the system. Therefore, the suppression of vibration is an unavoidable problem during milling. A novel partial surface damping method is proposed to modify the mode of the thin walled cantilever plate and to suppress vibration during milling. Based on classical plate theory, the design criterion is analyzed and configuration of the partial surface damper is introduced, in which viscoelastic plate and constraining plate are attached to the surface of the plate to increase the system＇s natural frequency and loss factor. In order to obtain the energy expression of the cutting system, the Ritz method is used to describe the unknown displacements. Then, with Lagrange＇s equation, the natural frequency and loss factor are calculated. In addition, the plate is divided into a finite number of square elements, and the regulation of treated position is studied based on theoretic and experimental analysis. The milling tests are conducted to verify its damping performance and the experimentalresults show that with treatment of partial surface damper, the deformation of the hare plate is reduced from 0.27 mm to 0.1 mm, while the vibration amplitude of the bare plate is reduced from 0.08 mm to 0.01 mm. The proposed research provides the instruction to design partial surface damper.

Mechanical Properties and Microstructure of Si_(3)N_(4)-TiC Nanocomposites

Si3N4/TiC nanocomposite ceramics have been fabricated by hot pressing technique with Al2O3 and Y2O3 as additives. The results showed that well dispersed composite powder was carried out by adding dispersant and adjusting pH values of suspensions. Remarkable increase in flexural strength at room temperatures was obtained by adding nanoparticles in Si3N4 matrix with 10% （wt pct） of nano-Si3N4 and 15% of nano-TiC. The flexural strength, fracture toughness and hardness were 1025 MPa, 7.5 MPa.m^1/2 and 15.6 GPa, respectively. The microstructures of materials were analyzed by scanning electron microscopy （SEM） and transmission electron microscopy （TEM）, which indicated that TiC nanoparticles distribute in the matrix and at the grain boundaries. According to the fracture form, low contents of nano particles could refine matrix grains and lead to the crack deflection as well as crack pinning. The multiplex microstructure was formed by mixing nano-Si3N4 particles. The crack trajectories exhibited crack deflection, rod-like grain bridging and pull-out.

Fabrication of solid CH-CD multilayer microspheres for inertial confinement fusion

Deuterated polymer microspheres can be used as a neutron source in conjunction with lasers because thermonuclear fusion neutrons can be produced efficiently by collisions of the resulting energetic deuterium ions.A new type of solid deuterated polymer microsphere with a carbon hydrogen–carbon deuterium(CH-CD)multilayer has been designed for preparing the target for inertial confinement fusion(ICF)experiments.To fabricate these solid CH-CD multilayer microspheres,CH beads are first fabricated by a microfluidic technique,and the CD coating layer is prepared by a plasma polymerization method.Both polystyrene(PS)and poly(α-methylstyrene)(PAMS)are used as the material sources for the CH beads.The effects of the PS and PAMS materials on the quality of the solid CH beads and the resulting CH-CD multilayer polymer microspheres are investigated.The solid PS beads have better sphericity and a smoother surface,but large vacuoles are observed in solid PS-CD multilayer microspheres owing to the presence of residual fluorobenzene in the beads and a glass transition temperature of the solid PS beads that is lower than the temperature of plasma polymerization.Therefore,solidPAMSbeads are more suitable as a mandrel for fabricating solid CH-CD multilayer polymer microspheres.Solid CH-CD multilayer microspheres with specified size have been successfully prepared by controlling the droplet size and the CD deposition rate and deposition time.Compared with the design value,the diameter deviation of the inner CH beads and the thickness deviation of the CD layer can be controlled within 20μmand 2μm,respectively.Thus,an approach has been developed to fabricate solid CH-CD multilayer microspheres that meet the physical design requirements for ICF.

Investigation of working pressure on the surface roughness controlling technology of glow discharge polymer films based on the diagnosed plasma

The effects of working pressure on the component, surface morphology, surface roughness, and deposition rate of glow discharge polymer （GDP） films by a trans-2-butene/hydrogen gas mixture were investigated based on plasma characteristics diagnosis. The composition and ion energy distributions of a multi-carbon （CaHs/H2） plasma mixture at different working pressures were diagnosed by an energy-resolved mass spectrometer （MS） during the GDP film deposition process. The Fourier transform infrared spectroscopy （FT-IR）, field emission scanning electron microscope （SEM） and white-fight interferometer （WLI） results were obtained to investigate the structure, morphology and roughness characterization of the deposited films, respectively. It was found that the degree of ionization of the C4H8/H2 plasma reduces with an increase in the working pressure. At a low working pressure, the C-H fragments exhibited small-mass and high ion energy in plasma. In this case, the film had a low CH3/CH2 ratio, and displayed a smooth surface without any holes, cracks or asperities. While the working pressure increased to 15 Pa, the largest number of large-mass fragments led to the deposition rate reaching a maximum of 2.11 #m h-1, and to hole defects on the film surface. However, continuing to increase the working pressure, the film surface became smooth again, and the interface between clusters became inconspicuous without etching pits.

绿色磷光发光层制备工艺对其组装柔性器件的性能影响

本文主要介绍了以CBP为主体发光材料,Ir(mppy)3为绿色磷光掺杂材料,优化发光层的制备工艺,制备高性能的柔性大尺寸绿色磷光器件。结果表明分别主客发光材料蒸镀温度在335℃和390℃,Ir(mppy)3掺杂量为8%,有机发光层厚度为35 nm时,制备得到柔性绿光OLEDs的光电性能最佳。当电压为9.5 V时,柔性器件获得最高发光效率为6.11 lm/W。在17V电压下,柔性器件发射出稳定均匀的绿光,其最大发光亮度为12580 cd/m^(2),电致发光光谱的峰值为512 nm,色坐标是(x=0.293,y=0.582),并且LT50寿命≥50h。

The natural course of bacillus Calmette-Guerin induced bladder lesions:A long-term follow-up study and systematic review

Objective:Bacillus Calmette-Gue´rin(BCG)instillation is the standard adjuvant treatment for intermediate-and high-risk non-muscle-invasive bladder cancer after transurethral resection.Nevertheless,its toxicity often causes bladder complications.On follow-up cystoscopy,post-BCG bladder lesions can be pathologically benign,urothelial carcinoma recurrence,or other types of bladder malignancy.Only a small number of case reports have been published on post-BCG bladder lesions.Their clinical features,natural course,and management remain unknown.Methods:We retrospectively studied cystoscopic videos and medical records of BCG-treated bladder cancer patients at our center.During a long-term follow-up,we took biopsies on tumor-like lesions and described their changes.In addition,we summarized previous studies on post-BCG bladder lesions by systematic literature searching and review.Results:We described a series of three cases with post-BCG bladder lesions mimicking tumor recurrence from a total of 38 cases with follow-up data for more than 5 years.Those lesions could last,grow,or disappear spontaneously,and remain pathological benign for years.In systematic review,we identified and analyzed a total of 15 cases with post-BCG bladder lesions with detailed clinical information.Eleven of the 15 were benign and have a good prognosis with nephrogenic adenoma being the most common pathological type.Conclusion:Based on previous studies and our experience,benign lesions after BCG instillation cannot distinguish with cancer recurrence by cystoscopy alone,even under narrow band imaging mode.Nonetheless,given most of them have a good prognosis,random biopsy or transurethral resection might be spared in the patients with long-term negative biopsy and urine cytology.

Penile vascular anomalies:A retrospective single center study and cumulative analysis of studies from China

Objective Penile vascular anomalies(PVAs)or hemangioma can arouse patient concern about aesthetics and cause symptoms like bleeding and sexual dysfunction.However,its low incidence and the deficiency of large-volume studies hinder urologists from making informed decisions.This study aimed to investigate the clinical features and treatment experience of PVAs at the Seventh Medical Center of PLA General Hospital,Beijing,China.Furthermore,by systematically analysis of studies on PVAs in Chinese people,we aimed to provide novel insights on the management of this condition.Methods We retrospectively investigated clinical features and pathology of surgery-treated PVAs at our center.Moreover,by systemically reviewing the literature from PubMed and the three largest medical databases(China National Knowledge Infrastructure,Wan Fang,and Chinese Medical Journal Database)in China,we analyzed the clinical features and various therapies of PVAs in Chinese people.Results Between March 1,2018 and March 1,2023,a total of 356 cases with vascular anomalies were treated with surgery at out center.Only seven(2.0%)cases had lesions involving the perineum and external genitalia.All the seven cases were pathologically benign and demonstrated no recurrence over a follow-up period of 1-52 months(median 14 months).A total of 410 cases from 44 studies were selected in the cumulative analysis.Most patients(92.4%)diagnosed with PVAs were asymptomatic,and 68.8%of the patients were treated with sclerotherapy.As to the pathology,57.1%were venous malformation.Conclusion The most common PVA is venous malformation and the majority of patients are asymptomatic.Sclerotherapy and laser have emerged as viable options for treating small lesions.Surgery still has its role in treating large lesions and obtaining pathology.Although PVAs often relapse or demand multiple treatments,the prognosis is favorable.

Should peritoneal tears be repaired during retroperitoneal laparoscopic radical nephrectomy?

To the Editor:Laparoscopic radical nephrectomy(LRN)is the standard of care for patients with T2 tumors and localized masses not treatable by partial nephrectomy according to the European Association of Urology Guidelines on renal cell carcinoma.[1]Transperitoneal and retroperitoneal are two main approaches in LRN.With the advantages of easier hilar control,shorter operation time,and less bowel irritation,retroperitoneal approach is preferable in our center.The peritoneal tear is a common intraoperative complication during retroperitoneoscopic procedures,leading to the collapse of the retroperitoneal space.

A novel stability prediction approach for thin-walled component milling considering material removing process

The milling stability of thin-walled components is an important issue in the aviation manufacturing industry, which greatly limits the removal rate of a workpiece. However, for a thin-walled workpiece, the dynamic characteristics vary at different positions. In addition, the removed part also has influence on determining the modal parameters of the workpiece. Thus,the milling stability is also time-variant. In this work, in order to investigate the time variation of a workpiece＇s dynamic characteristics, a new computational model is firstly derived by dividing the workpiece into a removed part and a remaining part with the Ritz method. Then, an updated frequency response function is obtained by Lagrange＇s equation and the corresponding modal parameters are extracted. Finally, multi-mode stability lobes are plotted by the different quadrature method and its accuracy is verified by experiments. The proposed method improves the computational efficiency to predict the time-varying characteristics of a thin-walled workpiece.

Comments on Thermal effect of holmium laser lithotripsy under ureteroscopy

To the Editor:We appreciate the work Wang et al[1]have done on thermal effect of holmium laser lithotripsy under ureteroscopy.Holmium laser is considered as the optimum lithotripter for ureteroscopy due to its effectiveness.[2]With the application of high-power laser system,the potential risk of ureter thermal injury increases.Several in-vitro and animal experiments have been carried out to assess temperature changes of lavage solution during laser activation recent years.To the best of our knowledge,this is the first human study revealing temperature changes of ureter lavage solution during holmium laser ureteroscopic lithotripsy.

Bonding mechanism and performance of ceramic coatings by sol-gel process

Thin alumina coatings were prepared on carbide tools to enhance their wear-resistant ability by dip coating from an aluminum alkoxide solution. The coating eventually obtained was perfectly integrated, without any macroscopic defect, and showed good performance in turning medium carbon steel, which presented a novel and promising coating method for cutting tools. The coating morphology before and after heat treatment was examined with the aid of a scanning electron microscope (SEM). The composition of coating and interface layer as well as the crystal structure of coating was characterized by X-ray diffraction (XRD). The elemental distribution near the interlayer was analyzed by electron probe microanalysis (EPMA).

Measurement of gear tooth dynamic deformation using dynamic speckle photography

A new method of measuring gear tooth dynamic deformation is proposed. Dynamic speckle photographs of the rotating gear tooth have been achieved by combining the pulsed ruby laser with the out-syn-signal. Double speckle patterns of the whole mesh period of gear tooth are obtained by accurate time delay of the ruby laser. Gear tooth dynamic deformation of the whole mesh period is achieved using the automatic image processing. Testing results show that the trends of gear tooth deformation coincides with the calculation by the finite element method. The success of this new trying provides a new technique for the measurement of gear tooth dynamic deformation.