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Thermoelastic stress analysis of multilayered films in a micro-thermoelectric cooling device

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Acta Mechanica Sinica 2012年第6期28卷 1644-1650页

作者： Yu-Mei Yang Xing-Zhe Wang wen-jie zhang Key Laboratory of Mechanics on Environment and Disaster in Western China The Ministry of Education of China College of Civil Engineering and Mechanics Lanzhou University

This paper presents an analytical solution for the thermoelastic stress in a typical in-plane＇s thin-film micro- thermoelectric cooling device under different operating con- ditions. The distributions of the permissible temperature fields in multilayered thin-films are analytically obtained, and the characteristics, including maximum temperature dif- ference and maximum refrigerating output of the thermo- electric device, are discussed for two operating conditions. Analytical expressions of the thermoelastic stresses in the layered thermoelectric thin-films induced by the tempera- ture difference are formulated based on the theory of mul- tilayer system. The results demonstrate that, the geometric dimension is a significant factor which remarkably affects the thermoelastic stresses. The stress distributions in layers of semiconductor thermoelements, insulating and support- ing membrane show distinctly different features. The present work may profitably guide the optimization design of high- efficiency micro-thermoelectric cooling devices.

关键词： Thermoelectric cooling device Multilayeredthin-film Thermoelastic stress - Analytical solution

Clean synthesis of calix[4]crown-5-sulfonyl cyclothiourea derivatives at room temperature in aqueous solution

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Chinese Chemical Letters 2009年第10期20卷 1166-1169页

作者： Cong wen Ding Ming jie zhang Ning Ma Chemistry Department of Science School Tianjin University Tianjin 300072 China

Calix[4]-crown-5-sulfonyl cyclothiourea derivatives 6 and 7 were synthesized from calix[4]-crown-5-monosulfonylethylenediamine derivatives 4 and 5 and carbon disulfide through nucleophilic addition and subsequent cyclization of intramolecule at room temperature in aqueous solution. The advantages of the novel protocol are the mild reaction condition, free organic solvent, simple final treatment, easy isolation of products and excellent yields.

关键词： Room temperature Aqueous solution Calix-crown-5-sttlfonyl cyclothiourea Clean synthesis

Hawking radiation of Dirac particles from soft-hairy black holes

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Communications in Theoretical Physics 2022年第4期74卷 68-71页

作者： wen-jie zhang Pu-Jian Mao Jun-Bao Wu Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin University University135 Yaguan RoadTianjin 300350China

In this paper,we study the Hawking radiation of Dirac particles via tunneling formalism from linearly supertranslated Schwarzschild black *** find that the radiation spectrum and the Hawking temperature remain the sam... 详细信息

关键词： quantum aspects of black holes quantum field theory in curved spacetime black hole thermodynamics

Numerical simulation of macrosegregation in continuously cast gear steel 20CrMnTi with final electromagnetic stirring

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Journal of Iron and Steel Research International 2021年第4期28卷 424-436页

作者： Sheng-kui Yin Sen Luo wen-jie zhang Wei-ling Wang Miao-yong Zhu Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

A 3D/2D hybrid multi-physical-field mathematical model,which takes into consideration the thermosolutal buoyance,was developed to predict the macrosegregation of gear steel 20CrMnTi continuously cast by a curved billet caster with size of 160 mm×160 mm,and investigated the effect of final electromagnetic stirring(F-EMS)on the fluid flow,heat transfer and solute distribution in the liquid core of continuously cast *** results show that the application of F-EMS eliminates the effect of thermosolutal buoyancy on the asymmetric distribution of carbon concentration in the cross section of billet and accelerates the final solidification of resident molten steel in the liquid core of strand,but promotes the negative carbon segregation near the billet *** the gear steel 20CrMnTi is cast at the temperature of 1803 K and speed of 1.7 m/min,the solidification end advances forward from 9.84 to 9.72 m,and center carbon segregation ratio of billet decreases from 1.24 to 1.17 with the increase in current density of F-EMS from 0 to 350 A.

关键词： Gear steel Macrosegregation Final electromagnetic stirring Numerical simulation Continuous casting

Influencing factors,prediction and prevention of depression in college students:A literature review

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World Journal of Psychiatry 2022年第7期12卷 860-873页

作者： Xin-Qiao Liu Yu-Xin Guo wen-jie zhang wen-Juan Gao School of Education Tianjin UniversityTianjin 300350China Graduate School of Education Peking UniversityBeijing 100871China Institute of Higher Education Beihang UniversityBeijing 100191China

The high prevalence of depression among college students has a strong negative impact on individual physical and mental health,academic development,and interpersonal *** paper reviewed the extant literature by identifying nonpathological factors related to college students'depression,investigating the methods of predicting depression,and exploring nonpharmaceutical interventions for college students'*** influencing factors of college students'depression mainly fell into four categories:biological factors,personality and psychological state,college experience,and *** outbreak of coronavirus disease 2019 has exacerbated the severity of depression among college students worldwide and poses grave challenges to the prevention and treatment of depression,given that the coronavirus has spread quickly with high infection rates,and the pandemic has changed the daily routines of college *** predict and measure mental health,more advanced methods,such as machine algorithms and artificial intelligence,have emerged in recent years apart from the traditional commonly used psychological *** nonpharmaceutical prevention measures,both general measures and professional measures for the prevention and treatment of college students'depression were examined in this *** who experience depressive disorders need family support and personalized interventions at college,which should also be supplemented by professional interventions such as cognitive behavioral therapy and online *** this literature review,we insist that the technology of identification,prediction,and prevention of depression among college students based on big data platforms will be extensively used in the *** education institutions should understand the potential risk factors related to college students'depression and make more accurate screening and prevention available with the help of advanced technologies.

关键词： Depression Prediction Prevention Artificial intelligence Big data Machine learning

Application of modified primary closure of the pelvic floor in laparoscopic extralevator abdominal perineal excision for low rectal cancer

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World Journal of Gastroenterology 2018年第30期24卷 3440-3447页

作者： Yan-Lei Wang Xiang zhang Jia-Jia Mao wen-Qiang zhang Hao Dong Fan-Pei zhang Shuo-Hui Dong wen-jie zhang Yong Dai Department of Colorectal and Anal Surgery Qilu Hospital of Shandong University

AIM To introduce a novel,modified primary closure technique of laparoscopic extralevator abdominal perineal excision(LELAPE) for low rectal *** We retrospectively analyzed data from 76 patients with rectal cancer who underwent LELAPE from March 2013 to May *** were classified into the modified primary closure group(32 patients) and the biological mesh closure group(44 patients).The total operating time,reconstruction time,postoperative stay duration,total cost,postoperative complications and tumor recur-rence were *** All surgery was successfully *** pelvic reconstruction time was 14.6 ± 3.7 min for the modified primary closure group,which was significantly longer than that of the biological mesh closure group(7.2 ± 1.9 min,P < 0.001).The total operating time was not different between the two groups(236 ± 20 min vs 248 ± 43 min,P = 0.143).The postoperative hospital stay duration was 8.1 ± 1.9 d,and the total cost was 9297 ± 1260 USD for the modified primary closure ***,both of these categories were significantly lower in this group than those of the biological mesh closure group(P = 0.001 and P = 0.003,respectively).There were no differences observed between groups when comparing other perioperative data,long-term complications or oncological *** The modified primary closure method for reconstruction of the pelvic floor in LELAPE for low rectal cancer is technically feasible,safe and cost-effective.

关键词： Extralevator abdominoperineal excision Rectal cancer Pelvic floor Laparoscopy

Prediction of risk factors for lymph node metastasis in early gastric cancer

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World Journal of Gastroenterology 2013年第20期19卷 3096-3107页

作者： Gang Ren Rong Cai wen-jie zhang Jin-Ming Ou Ye-Ning Jin wen-Hua Li Department of Radiology Xinhua HospitalShanghai Jiaotong University Medical School Department of Radiochemotherapy Ruijin HospitalShanghai Jiaotong University Medical School Department of Surgery Xinhua HospitalShanghai Jiaotong University Medical School

AIM:To explore risk factors for lymph node metastases in early gastric cancer(EGC) and to confirm the appropriate range of lymph node ***:A total of 202 patients with EGC who underwent curative gastrectomy with lymphadenectomy in the Department of Surgery,Xinhua Hospital and Ruijin Hospital of Shanghai Jiaotong University Medical School between November 2003 and July 2009,were retrospectively *** the surgical procedure and the extent of lymph node dissection were based on the recommendations of the Japanese gastric cancer treatment *** macroscopic type was classified as elevated(type Ⅰ or Ⅱa),flat(Ⅱb),or depressed(Ⅱc or Ⅲ).Histopathologically,papillary and tubular adenocarcinomas were grouped together as differentiated adenocarcinomas,and poorly differentiated and signet-ring cell adenocarcinomas were regarded as undifferentiated *** and multivariate analyses of lymph node metastases and patient and tumor characteristics were ***:The lymph node metastases rate in patients with EGC was 14.4%.Among these,the rate for mucosal cancer was 5.4%,and 8.9% for submucosal *** analysis showed an obvious correlation between lymph node metastases and tumor location,depth of invasion,morphological classification and venous invasion(χ 2 = 122.901,P = 0.001;χ 2 = 7.14,P = 0.008;χ 2 = 79.523,P = 0.001;χ 2 = 8.687,P = 0.003,respectively).In patients with submucosal cancers,the lymph node metastases rate in patients with venous invasion(60%,3/5) was higher than in those without invasion(20%,15/75)(χ 2 = 4.301,P = 0.038).Multivariate logistic regression analysis revealed that the depth of invasion was the only independent risk factor for lymph node metastases in EGC [P = 0.018,Exp(B) = 2.744].Among the patients with lymph node metastases,29 cases(14.4%) were at N1,seven cases were at N2(3.5%),and two cases were at N3(1.0%).Univariate analysis of variance revealed a close relationship between the dep

关键词： Gastric neoplasm Lymph node metastasis Risk factors Gastrectomy Lymphadenectomy

Comparison of ultrasound biomicroscopy and spectraldomain anterior segment optical coherence tomography in evaluation of anterior segment after laser peripheral iridotomy

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International Journal of Ophthalmology(English edition) 2016年第3期9卷 417-423页

作者： Xiao-Yun Ma Dan Zhu Jun Zou wen-jie zhang Yi-Lin Cao Department of Plastic and Reconstructive Surgery Shanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghai Key Laboratory of Tissue EngineeringNational Tissue Engineering Center of China Department of Ophthalmology Shanghai Guanghua Integrative Medicine Hospital Department of Ophthalmology Shanghai Tenth People's HospitalTongji University

AIM：To quantitatively assess narrow anterior chamber angle using spectral-domain anterior segment optical coherence tomography（SD-AS-OCT） and ultrasound biomicroscopy（UBM）,and to evaluate the correlations and consistency between SD-AS-OCT and UBM.· METHODS：Fifty-five eyes from 40 patients were *** were diagnosed with primary angleclosure glaucoma（PACG） remission（11 eyes from 8patients）,primary angle closure（PAC,20 eyes from 20patients） and PAC suspect（24 eyes from 12 patients）.Each eye was examined by SD-AS-OCT and UBM after laser peripheral iridotomy（LPI）.The measurements of SD-AS-OCT were angle open distance（AOD）,anterior chamber angle（ACA）,trabecular iris angle（TIA）,and trabecular iris space area（TISA）.UBM measurements were AOD and *** of AOD500 and TIA500 between UBM and AS-OCT were *** parameters were analysed by SPSS 16.0 and MedCalc.· RESULTS：ACA,TIA and AOD measured by SD-ASOCT reached a maximum at the temporal quadrant and minimum at the nasal *** parameters of AOD500 and AOD750 showed a linear positive correlation,and AOD750 had less *** outcomes of AOD500 and TIA500 were significantly smaller than those of *** results of the two techniques were correlated at the superior,nasal and inferior ***：Both UBM and SD-AS-OCT are efficient tools for follow-up during the course of *** recommended using parameters at 750 μm anterior to the sclera spur for the screening and follow-up of PACG and *** two methods might be alternatives to each other.

关键词： primary angle-closure glaucoma ultrasoundbiomicroscopy spectral-domain anterior segment opticalcoherence tomography laser peripheral iridotomy

Application of the interventional limb raising management strategy(ILRMS) at radial vascular access sites in coronary angiography and percutaneous coronary intervention:A randomized trial

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International Journal of Nursing Sciences 2016年第1期3卷 54-57页

作者： wen-jie zhang Jin-Chuan Yan Zhong-Qun Wang Department of Cardiology Affiliated Hospital of Jiangsu UniversityZhenjiangChina

Purpose:To compare the effectiveness of the interventional limb raising management strategy(ILRMS)to elastic bandage compression at radial vascular access sites following coronary angiographies(CAGs)and percutaneous coronary interventions(PCIs).Methods:Patients with ischemic coronary heart disease whose condition was stable over three months were enrolled in this clinical study(n=590;aged 25e80).All participants had just undergone CAG and *** were randomized into either the ILRMS group(n=360)or standard post-intervention care with an elastic bandage(n=230).Overall comfort and wrist pain was assessed and the degree of index finger swelling and oxygen saturation was measured on the affected *** variables were measured prior to postintervention treatment and again at six hours after CAG and ***:We found that patients receiving ILRMS had significantly lower wrist pain scores and swelling around the index finger compared to the elastic bandage group(p0.05).We also found that 19.57%of the elastic bandage patients were comfortable,while ILRMS patients were significantly more comfortable(93.06%;p<0.05).Conclusions:We find that ILRMS alleviates swelling and pain of the wrist more effectively than current practices and improves the degree of overall comfort of patients who undergo CAG and PCI.

关键词： Interventional limb raising management strategy Coronary angiography Percutaneous coronary intervention Nursing