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Grindability Evaluation of Ultrasonic Assisted Grinding of Silicon Nitride Ceramic Using Minimum Quantity Lubrication Based SiO_(2)Nanofluid 被引量:2
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作者 Yusuf Suleiman Dambatta Changhe Li +8 位作者 Mohd Sayuti Ahmed A D Sarhan Min Yang Benkai Li Anxue Chu Mingzheng Liu Yanbin Zhang Zafar Said Zongming Zhou 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期115-136,共22页
Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL ... Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL system is affirmed to exhibit an excellent machining performance,and it is highly economical.The nanofluids are understood to exhibit excellent lubricity and heat evacuation capability,compared to pure oil-based MQL system.Studies have shown that the surface quality and amount of energy expended in the grinding operations can be reduced considerably due to the positive effect of these nanofluids.This work presents an experimental study on the tribological performance of SiO_(2)nanofluid during grinding of Si_(3)N_(4)ceramic.The effect different grinding modes and lubrication systems during the grinding operation was also analyzed.Different concentrations of the SiO_(2)nanofluid was manufactured using canola,corn and sunflower oils.The quantitative evaluation of the grinding process was done based on the amount of grinding forces,specific grinding energy,frictional coefficient,and surface integrity.It was found that the canola oil exhibits optimal lubrication performance compared to corn oil,sunflower oil,and traditional lubrication systems.Additionally,the introduction of ultrasonic vibrations with the SiO_(2)nanofluid in MQL system was found to reduce the specific grinding energy,normal grinding forces,tangential grinding forces,and surface roughness by 65%,57%,65%,and 18%respectively.Finally,regression analysis was used to obtain an optimum parameter combinations.The observations from this work will aid the smooth transition towards ecofriendly and sustainable machining of engineering ceramics. 展开更多
关键词 Minimum quantity lubrication(MQL) Ultrasonic assisted grinding(UAG) Eco-friendly lubricants NANOFLUID GRINDING CERAMIC
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Diagnosis of poorly differentiated adenocarcinoma of the stomach by confocal laser endomicroscopy:A case report 被引量:3
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作者 Jia-Xin Lou Yong Wu +3 位作者 Muren Huhe Jing-Jie Zhang Dong-Wu Jia Zhen-Yu Jiang 《World Journal of Clinical Cases》 SCIE 2024年第8期1481-1486,共6页
BACKGROUND In recent years,confocal laser endomicroscopy(CLE)has become a new endoscopic imaging technology at the microscopic level,which is extensively performed for real-time in vivo histological examination.CLE ca... BACKGROUND In recent years,confocal laser endomicroscopy(CLE)has become a new endoscopic imaging technology at the microscopic level,which is extensively performed for real-time in vivo histological examination.CLE can be performed to distinguish benign from malignant lesions.In this study,we diagnosed using CLE an asymptomatic patient with poorly differentiated gastric adenocarcinoma.CASE SUMMARY A 63-year-old woman was diagnosed with gastric mucosal lesions,which may be gastric cancer,in the small curvature of the stomach by gastroscopy.She consented to undergo CLE for morphological observation of the gastric mucosa.Through the combination of CLE diagnosis and postoperative pathology,the intraoperative CLE diagnosis was considered to be reliable.According to our experience,CLE can be performed as the first choice for the diagnosis of gastric cancer.CONCLUSION CLE has several advantages over pathological diagnosis.We believe that CLE has great potential in the diagnosis of benign and malignant gastric lesions. 展开更多
关键词 Confocal laser endomicroscopy poorly differentiated gastric adenocarcinoma DIAGNOSIS Early stage Case report
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Associated Factors to Poor Blood Pressure Control in Hypertensives Followed Up at the Campus University Hospital of Lome (Togo)
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作者 Soulemane Pessinaba Yaovi Mignazonzon Afassinou +9 位作者 Wiyao Dieudonné Kaziga Komlavi Yayehd Kolani Lamboni Sélim Bolarinwa Mohamed Kpélafia Ekpe Togbossi Akpe Adzodo Machihude Pio Soodougoua Baragou Findibé Damorou 《World Journal of Cardiovascular Diseases》 CAS 2024年第6期374-380,共7页
Introduction: Hypertension is a real public health issue and its control is very difficult. We aim to determine the frequency of uncontrolled hypertension in hypertensive patients followed up as an outpatient at the c... Introduction: Hypertension is a real public health issue and its control is very difficult. We aim to determine the frequency of uncontrolled hypertension in hypertensive patients followed up as an outpatient at the campus university hospital of Lome (Togo) and to search for the associated factors. Methodology: The study was cross-sectional, descriptive and analytical, carried out from February (2022) to August 2022 in 260 hypertensive patients aged 22 years old, followed up (on an) as an outpatient for at least 3 months at the Lome University Hospital campus. A univariate then multivariate analysis were conducted in order to highlight the most common factors significantly linked to uncontrolled. Results: The mean age of hypertensives was 56.4 ± 12.7 years, the sex ratio (M/F) was 0.59. Prevalence of uncontrolled blood pressure was 42%. Associated Factors to poor blood pressure control in our study were age > 60 years (OR = 1.6 CI [1.17 - 2.50]), low socio-economic level (OR = 2.2 CI [1.96 - 4.33]), high cardiovascular risk level (OR = 3.1 CI [2.18 - 4.52]), non-adherence to regular blood pressure monitoring (OR = 3.3 CI [2.21 - 5.55]), low compliance to treatment (OR = 4.1 CI [2.33 - 6.76]) and a chronic renal failure (OR = 2.1 CI [1.21 - 3.10]). Conclusion: Nearly half of the hypertensives in our study had poorly controlled blood pressure by antihypertensive treatment medication. The factors of this poor control were age > 60 years, low socio-economic level, high or very high level of cardiovascular risk, low compliance to treatment, and renal failure. 展开更多
关键词 HYPERTENSION poor Control Associated factors TOGO
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Fluorographene with Narrow Lateral Size and Thickness Distributions Prepared for Enhancing Lubrication Performance of Bentonite Grease
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作者 XIANG Shuo LU Peng +6 位作者 ZHANG Qinhui XIAO Bowen YANG Xin ZHANG Peili MA Pengfei HE Yan LI Xuebin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第5期1294-1302,共9页
Fluorographene(FG)with narrow lateral size and thickness distributions was prepared by a liquid-phase exfoliation method,based on liquid cascade centrifugation.The Rtec MFT-5000 tribo-meter was used to investigate the... Fluorographene(FG)with narrow lateral size and thickness distributions was prepared by a liquid-phase exfoliation method,based on liquid cascade centrifugation.The Rtec MFT-5000 tribo-meter was used to investigate the lubricating performance of bentonite grease enhanced by the as-prepared FG.The results showed that the coefficient of friction and the wear volume of bentonite grease with 0.3 wt%FG were decreased by 20.4%and 44.9%,respectively,as compared to those of the base grease.The main reason is that FG can promote the formation of the tribo-chemical reaction film consisting of complex carbon oxide,Fe_(2)O_(3)and FeF_(3)on the friction surface,which can remarkably improve the performance of friction reduction and prevent the appearance of severe wear. 展开更多
关键词 fluorographene liquid-phase exfoliation bentonite grease lubrication performance
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Gallbladder carcinosarcoma with a poor prognosis: A case report
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作者 Yi Dai Min Meng +3 位作者 Qi-Zhi Luo Yuan-Jun Liu Fan Xiao Chun-Hua Wang 《World Journal of Clinical Cases》 SCIE 2024年第10期1817-1823,共7页
BACKGROUND Carcinosarcoma of the gallbladder is a rare malignant tumor with a very poor prognosis.To date,only approximately 100 patients have been reported in the English literature.The prognosis of this tumor type i... BACKGROUND Carcinosarcoma of the gallbladder is a rare malignant tumor with a very poor prognosis.To date,only approximately 100 patients have been reported in the English literature.The prognosis of this tumor type is poor,the preoperative diagnosis is difficult,and there is a possibility of a misdiagnosis.We present an unsuccessful case of carcinosarcoma of the gallbladder with a preoperative misdiagnosis and rapid early postoperative recurrence.Therefore,we have a deeper understanding of the poor prognosis of gallbladder carcinosarcoma(GBC)patients.CASE SUMMARY The patient is a 65-year-old male.He was admitted to the hospital because of right upper abdomen distending pain and discomfort for half a month.Abdominal magnetic resonance imaging revealed a polycystic mass in the right lobe of the liver and the fossa of the gallbladder.After admission,the patient was diagnosed with a liver abscess,which was treated by abscess puncture drainage.Obviously,this treatment was unsuccessful.Hepatectomy and cholecystectomy were performed one month after the puncture.Postoperative pathologic examination revealed carcinosarcoma of the gallbladder,and the resected specimen contained two tumor components.One month after surgery,the patient's tumor recurred in situ and started to compress the duodenum,resulting in duodenal obstruction and bleeding.The treatment was not effective.The patient died of gastrointestinal hemorrhage and hypovolemic shock.CONCLUSION Carcinosarcoma of the gallbladder is a rare malignant tumor that is easily misdiagnosed preoperatively and has a poor prognosis. 展开更多
关键词 Gallbladder disease CARCINOSARCOMA MISDIAGNOSIS poor prognosis Pathological diagnosis RECURRENCE Case report
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Autosomal Dominant Polycystic Kidney Disease: Epidemiological, Clinical Aspects and Predictive Factors of Poor Renal Prognosis (About 300 Cases)
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作者 Rihab Dkhissi Nada El Kadiri +2 位作者 Tarik Bouattar Loubna Benamar Naima Ouzeddoun 《Open Journal of Nephrology》 2024年第2期275-293,共19页
Introduction: Autosomal dominant polycystic kidney disease (ADPKD) is a common, multisystemic, and progressive hereditary disease. It accounts for 6 to 8% of incident cases of end-stage chronic renal disease (ESRD) in... Introduction: Autosomal dominant polycystic kidney disease (ADPKD) is a common, multisystemic, and progressive hereditary disease. It accounts for 6 to 8% of incident cases of end-stage chronic renal disease (ESRD) in developed countries. The aim of this study is to describe the predictive factors for the development of end-stage chronic kidney disease (CKD) in the course of this disease. Material and Methods: This is a retrospective, descriptive, and analytical study including 300 cases of ADPKD collected at the Nephrology Department of Ibn-Sina Hospital in Rabat over a period of 30 years (1993 to 2023). Included in the study are all patients with ADPKD meeting the ultrasound diagnostic criteria. The analysis focused on demographic, clinical, paraclinical, evolutionary data, as well as prognostic factors associated with renal function deterioration. Results: The mean age of patients at diagnosis is 51.53 +/− 17 years [16 - 93] with a male predominance. The median serum creatinine at diagnosis is 15.5 mg/l [10 - 34]. 21% of patients had ESRD (eGFR 300 mg/24h (21%). The most common cystic complication is hemorrhage (12.3%). 21.3% of patients had hepatorenal polycystic disease. In adjusted analysis, the predictive risk factors for the occurrence of ESRD were smoking (p = 0.019), anemia (p Conclusion: ADPKD can progress insidiously to ESRD. Identification and early treatment of predictive factors for poor renal prognosis could contribute to a better outcome for this disease. 展开更多
关键词 ADPKD ESRD Factors of poor Renal Prognosis Renal and Extra-Renal Manifestations
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Electrostatic spraying for fine-tuning particle dimensions to enhance oral bioavailability of poorly water-soluble drugs
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作者 Jung Suk Kim Seunghyun Cheon +10 位作者 Mi RanWoo Sanghyun Woo Jee-Eun Chung Yu Seok Youn Kyung Taek Oh Soo-Jeong Lim Sae Kwang Ku Bao LoNguyen Jong Oh Kim Sung Giu Jin Han-Gon Choi 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2024年第5期139-151,共13页
While spray-drying has been widely utilized to improve the bioavailability of poorly water-soluble drugs,the outcomes often exhibit suboptimal particle size distribution and large particle sizes,limiting their effecti... While spray-drying has been widely utilized to improve the bioavailability of poorly water-soluble drugs,the outcomes often exhibit suboptimal particle size distribution and large particle sizes,limiting their effectiveness.In this study,we introduce electrostatic spraying as an advanced technology tailored for poorly water-soluble drugs,enabling the fabrication of nanoparticles with fine and uniform particle size distribution.Regorafenib(1 g),as a model drug,copovidone(5 g),and sodium dodecyl sulfate(0.1 g)were dissolved in 200 ml ethanol and subjected to conventional-spray-dryer and electrostatic spray dryer.The electrostatic spray-dried nanoparticles(ESDN)showed smaller particle sizes with better uniformity compared to conventional spray-dried nanoparticles(CSDN).ESDN demonstrated significantly enhanced solubility and rapid release in water.In vitro studies revealed that ESDN induced apoptosis in HCT-116 cells to a greater extent,exhibiting superior cytotoxicity compared to CSDN.Furthermore,ESDN substantially improved oral bioavailability and antitumor efficacy compared to CSDN.These findings suggest that ESD shows potential in developing enhanced drug delivery systems for poorly water-soluble drugs,effectively addressing the limitations associated with CSD methods. 展开更多
关键词 Electrostatic spray drying poorly water-soluble drug Regorafenib Particle size distribution Oral bioavailability Oral antitumor efficacy
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Discussion on the Ideological and Political Education for Poor College Students
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作者 Jie Li Yang Liu +1 位作者 Shuang Liu Cen Yan 《Journal of Contemporary Educational Research》 2024年第1期133-139,共7页
At present,ideological and political education is significant for poor college students.The focus of funding for poor students has gradually transformed from providing economic support for them to ideological and spir... At present,ideological and political education is significant for poor college students.The focus of funding for poor students has gradually transformed from providing economic support for them to ideological and spiritual help,which puts forward higher requirements on how to carry out ideological and political work.It also requires us to advance the work of ideological and moral education and put it in the most important position in the ideological and educational work for poor college students.Combined with the reality of poor college students,we will adhere to the idea of being student-oriented and endeavor to enhance the effectiveness,pertinence,and relevance of the work of ideological and political education.This paper analyzes the significance and problems of ideological and political education for poor college students and puts forward effective ways to solve the problems from the levels of ideology,cognition,and teaching staff. 展开更多
关键词 Ideological and political education poor college students Mechanism improvement
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Superlubricity behaviors of Nitinol 60 alloy under oil lubrication 被引量:6
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作者 曾群锋 董光能 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第2期354-359,共6页
The tribological tests were performed using Nitinol 60 alloy pin sliding over GCr15 steel disc in the tribometer system. Four kinds of oils were experimentally investigated as lubrication oils for lubricating Nitinol ... The tribological tests were performed using Nitinol 60 alloy pin sliding over GCr15 steel disc in the tribometer system. Four kinds of oils were experimentally investigated as lubrication oils for lubricating Nitinol 60 alloy in the boundary lubrication regime. The experimental results were compared with a reference dry friction. It was found that Nitinol 60 alloy can be lubricated significantly and has shown remarkable lubrication performance. A superlubricity behavior of Nitinol 60 alloy was observed under castor oil lubrication. An ultra-low coefficient of friction of Nitinol 60 alloy about 0.008 between Nitinol 60 alloy and GCr15 steel was obtained under castor oil lubrication condition after a running-in period. Accordingly, the present study is focused on the lubrication behaviors of castor oil as potential lubrication oil for Nitinol 60 alloy. In the presence of castor oil, coefficient of friction is kept at 0.008 at steady state, corresponding to so-called superlubricity regime (when sliding is then approaching pure rolling). The mechanism of superlubricity is attributed to the triboformed OH-terminated surfaces from friction-induced dissociation of castor oil and the boundary lubrication films formed on the contact surface due to high polarity and long chain of castor oil allowing strong interactions with the lubricated surfaces. 展开更多
关键词 Nitinol 60 alloy oil lubrication SUPERLUBRICITY lubrication films
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Lubrication properties of Nitinol 60 alloy used as high-speed rolling bearing and numerical simulation of flow pattern of oil-air lubrication 被引量:2
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作者 曾群锋 赵西朦 +1 位作者 董光能 吴红星 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第10期2431-2438,共8页
The friction and wear tests were performed using Nitinol 60 alloy pin sliding over GCr15 steel disk in a pin-on-disk tribometer system under PAO oil lubrication conditions. It was found that Nitinol 60 alloy can be lu... The friction and wear tests were performed using Nitinol 60 alloy pin sliding over GCr15 steel disk in a pin-on-disk tribometer system under PAO oil lubrication conditions. It was found that Nitinol 60 alloy can be lubricated well and has shown remarkable tribological performance. Average coefficient of friction (COF) of Nitinol 60 is 0.6 under dry friction; however, average COF decreases to 0.1 under PAO oil lubrication. SEM image of the worn surface shows that Nitinol 60 exhibits excellent wear resistance and the wear mechanism is mainly adhesive wear. Flow pattern of oil-air flow in oil pipe was simulated by FLUENT software with VOF model for acquiring working performance of oil-air lubrication. The optimum velocity of oil and air at the inlet was achieved, which provides the great proposal for the design of experiment of oil-air lubrication of Nitinol 60 alloy. The simulation results showed that the optimum annular flow of flow pattern was obtained when air velocity is 10 m/s and oil velocity is 0.05 m/s. The formation mechanism of annular flow was also discussed in the present study. 展开更多
关键词 Nitinol 60 alloy lubrication properties oil-air lubrication numerical simulation two-phase flow
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EFFECT OF COOLING/LUBRICATION MEDIUM ON MACHINABILITY OF Ti6Al4V 被引量:5
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作者 戚宝运 何宁 李亮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第3期225-230,共6页
To better understand and know the roles of cooling/lubrication medium in the cutting process and expand their applicability,uncoated cemented carbide tools are used in high-speed turning Ti6Al4V.Dry,cold air,minimal q... To better understand and know the roles of cooling/lubrication medium in the cutting process and expand their applicability,uncoated cemented carbide tools are used in high-speed turning Ti6Al4V.Dry,cold air,minimal quantity lubrication(MQL),cryogenic MQL,and ionized air as the cooling/lubrication conditions are studied.Experimental results show that at speed 120 m/min turning Ti6Al4V,the cutting force under ionized air is smallest under all lubricant conditions,and tool life is best,next is cryogenic MQL.MQL and cold air almost have the same effect,a little better than dry.Meanwhile the smallest surface roughness is also obtained under ionized air condition.Flank wear and crater wear are the dominant failure modes when high-speed turning Ti6Al4V by SEM analysis.Finally the conclusion is drawn that ionized air and cryogenic MQL have better cooling/lubrication effects and can effectively improve the tool life. 展开更多
关键词 cooling/lubrication high-speed turning TI6AL4V minimal quantity lubrication(MQL) ionized air
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THERMOHYDRODYNAMIC LUBRICATION ANALYSIS ON EQUILIBRIUM POSITION AND DYNAMIC COEFFICIENT OF JOURNAL BEARING 被引量:1
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作者 李元生 于明 +1 位作者 敖良波 岳珠峰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第3期227-236,共10页
The finite element method (FEM) is introduced to calculate the oil film pressure and temperature distribution of a journal bearing. The perturbation is performed directly on the finite element equation. Consequently... The finite element method (FEM) is introduced to calculate the oil film pressure and temperature distribution of a journal bearing. The perturbation is performed directly on the finite element equation. Consequently, the Jacobian matrices of the oil film forces are concisely obtained. The equilibrium position of the bearing with a given static load is found by the Newton-Raphson method. As byproducts, dynamic coefficients are obtained simultaneously without any extra computing time. From the numerical results, it is concluded that the effects of film temperature on stiffness coefficients are bigger than those on damping coefficients. With the increase of rotational speed, the load capacity and the stiffness coefficients of the journal bearing are increased when the eccentricity is small, while decreased when the eccentricity is big. 展开更多
关键词 thermohydrodynamic lubrication thermal effect finite element analysis journal bearing
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Dynamic Simulation Study of Friction and Lubrication on ICE Bearings 被引量:2
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作者 王文清 王静 《Journal of Beijing Institute of Technology》 EI CAS 2000年第4期459-464,共6页
Friction and lubrication simulation analysis of internal combustion engine bearings are studied. A series of software implementary precepts for mathematical modeling, to analytic calculating and realizing simulation o... Friction and lubrication simulation analysis of internal combustion engine bearings are studied. A series of software implementary precepts for mathematical modeling, to analytic calculating and realizing simulation outcome are brought forward. As a dynamic simulating technique is introduced into the process of engine bearing design, simulation models of the oil film are built and the emulational analysis of the shaft center track is carried out. A software program package “Engine Bearing Friction and Lubrication Dynamic Simulation System” is developed to realize the real time simulation of the working status of bearing during the design process. Through developing virtualized products, the defects of the product design can be found in time and improve the products at once. Thus the purpose of predicting and controlling the cost, quality and design period of the products can be achieved. 展开更多
关键词 internal combustion engine bearings friction and lubrication SIMULATION
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A fatigue life prediction method of rolling bearing under elliptical contact elastohydrodynamic lubrication 被引量:1
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作者 路春雨 刘少军 《Journal of Southeast University(English Edition)》 EI CAS 2017年第1期46-52,共7页
In order to more accurately predict the contact fatigue life of rolling bearing, a prediction method of fatigue life of rolling bearing is proposed based on elastohydrodynamic lubrication (EHL), the 3-paameter Weibu... In order to more accurately predict the contact fatigue life of rolling bearing, a prediction method of fatigue life of rolling bearing is proposed based on elastohydrodynamic lubrication (EHL), the 3-paameter Weibull distribution ad fatigue strength. First,the contact stress considering elliptical EHL is obtained by mapping film pressure onto the Hertz zone. Then,the basic strength model of rolling bearing based on the 3-parameter Weibull distribution is deduced by the series connection reliability theory. Considering the effect of the type of stress, variation of shape and fuctuation of load, the mathematical models of the 尸 -tS-TV curve of the minimum life and the characteristic life for rolling bearing are established, respectively, and thus the prediction model of fatigue life of rolling bearing based on the 3-paameter Weibull distribution and fatigue strength is further deduced. Finally, the contact fatigue life obtained by the proposed method ad the latest international standard (IS0281: 2007) about the fatigue life prediction of rolling bearing are compared with those obtained by the statistical method. Results show that the proposed prediction method is effective and its relative error is smaier than that of the latest international standard (IS0281: 2007) with reliability R 〉 0. 93. 展开更多
关键词 rolling bearing 3-parameter Weibull distribution elastohydrodynamic lubrication (EHL) fatigue strength contact fatigue life
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Selection of Cotton Variety Suitable for Cottonwheat Intercropping in Rainy and Poor Sunshine Years
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作者 王树林 刘文艺 +5 位作者 祁虹 王燕 张谦 冯国艺 林永增 梁青龙 《Agricultural Science & Technology》 CAS 2016年第9期2008-2011,2036,共5页
The year of 2013 is a typical rainy and poor sunshine year, and the monthly sunshine hours from May to October were all lower than the average, which from July to September was only 69.3%,71.1% and 56.2% of average, r... The year of 2013 is a typical rainy and poor sunshine year, and the monthly sunshine hours from May to October were all lower than the average, which from July to September was only 69.3%,71.1% and 56.2% of average, respectively. In cotton-wheat system 10 cotton varieties (lines) were planted to select the most suitable varieties for cotton-wheat system in rainy and poor sunshine years through investigating cotton growing traits in 2013. The results showed that in cotton-wheat system the vegetative growth of cotton was mainly from late June to middle July especially in rainy and poor sunshine years. And with the increase of the cotton growth period the peak of vegetative growth delayed, the ratio of the autumn bolls increased, and the ratio of pre-frost yield decreased. In all the varieties unginned cottonyield of Zhongmiansuo 50 with shorter growth period, higher rate of summer bolls and better fiber quality, seed yield reached 3 814.1 kg/hm2, higher than that of other varieties (lines) significantly, and the rate of pre-frost yield reached 83.4%, which was the most suitable variety for cotton-wheat system in rainy and poor sunshine years. 展开更多
关键词 Rainy and poor sunshine Cotton-wheat intercropping Cotton Variety selection
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MoS_(2)Lubricate‑Toughened MXene/ANF Composites for Multifunctional Electromagnetic Interference Shielding
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作者 Jiaen Wang Wei Ming +8 位作者 Longfu Chen Tianliang Song Moxi Yele Hao Zhang Long Yang Gegen Sarula Benliang Liang Luting Yan Guangsheng Wang 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期358-371,共14页
The design and fabrication of high toughness electromagnetic interference(EMI)shielding composite films with diminished reflection are an imperative task to solve electromagnetic pollution problem.Ternary MXene/ANF(ar... The design and fabrication of high toughness electromagnetic interference(EMI)shielding composite films with diminished reflection are an imperative task to solve electromagnetic pollution problem.Ternary MXene/ANF(aramid nanofibers)–MoS_(2)composite films with nacre-like layered structure here are fabricated after the introduction of MoS_(2)into binary MXene/ANF composite system.The introduction of MoS_(2)fulfills an impressive“kill three birds with one stone”improvement effect:lubrication toughening mechanical performance,reduction in secondary reflection pollution of electromagnetic wave,and improvement in the performance of photothermal conversion.After the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 50:50),the strain to failure and tensile strength increase from 22.1±1.7%and 105.7±6.4 MPa and to 25.8±0.7%and 167.3±9.1 MPa,respectively.The toughness elevates from 13.0±4.1 to 26.3±0.8 MJ m^(−3)(~102.3%)simultaneously.And the reflection shielding effectiveness(SE_(R))of MXene/ANF(mass ratio of 50:50)decreases~10.8%.EMI shielding effectiveness(EMI SE)elevates to 41.0 dB(8.2–12.4 GHz);After the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 60:40),the strain to failure increases from 18.3±1.9%to 28.1±0.7%(~53.5%),the SE_(R)decreases~22.2%,and the corresponding EMI SE is 43.9 dB.The MoS_(2)also leads to a more efficient photothermal conversion performance(~45 to~55℃).Additionally,MXene/ANF–MoS_(2)composite films exhibit excellent electric heating performance,quick temperature elevation(15 s),excellent cycle stability(2,2.5,and 3 V),and long-term stability(2520 s).Combining with excellent mechanical performance with high MXene content,electric heating performance,and photothermal conversion performance,EMI shielding ternary MXene/ANF–MoS_(2)composite films could be applied in many industrial areas.This work broadens how to achieve a balance between mechanical properties and versatility of composites in the case of high-function fillers. 展开更多
关键词 MXene-MoS_(2) lubrication toughening EMI shielding Photothermal conversion Electric heating performance
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基底材料对润滑油中金属元素LIBS检测的影响
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作者 赵静怡 段皓 +2 位作者 蔡明洋 李倩 李业秋 《沈阳理工大学学报》 CAS 2025年第1期78-84,共7页
润滑油中金属元素的含量和成分的变化能反映发动机的使用状态。通过对比四种基底(Al、Ni、Zn、Cu)增强下润滑油中金属元素BaⅡ455.4 nm的激光诱导击穿光谱(LIBS)特性,对不同基底材料的激发效果进行了评价,并利用多元线性回归模型建立了B... 润滑油中金属元素的含量和成分的变化能反映发动机的使用状态。通过对比四种基底(Al、Ni、Zn、Cu)增强下润滑油中金属元素BaⅡ455.4 nm的激光诱导击穿光谱(LIBS)特性,对不同基底材料的激发效果进行了评价,并利用多元线性回归模型建立了Ba元素激发效果与基底元素物理特性的联系。结果表明:第一电离能、蒸发潜热、热传导率对润滑油中金属元素的激发效果影响较小,且呈正相关;相对原子质量、原子序数、熔化潜热、密度对润滑油中金属元素的激发效果影响较大,且呈负相关。该结果为润滑油金属元素LIBS检测过程中基底材料的选择提供了依据,并为提高金属元素检测准确率和检出限提供了一种可行性方案,对发动机故障检测有重要意义。 展开更多
关键词 激光诱导击穿光谱 润滑油 基底材料 多元线性回归
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Oncogenic ADAM28 induces gemcitabine resistance and predicts a poor prognosis in pancreatic cancer 被引量:7
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作者 Li Wei Jing-Yun Wen +4 位作者 Jie Chen Xiao-Kun Ma Dong-Hao Wu Zhan-Hong Chen Jiang-Long Huang 《World Journal of Gastroenterology》 SCIE CAS 2019年第37期5590-5603,共14页
BACKGROUND Pancreatic cancer is a major cause of cancer-related death,with a 5-year overall survival rate being below 5%.The main causes of poor prognosis in pancreatic cancer include easy metastasis,high recurrence r... BACKGROUND Pancreatic cancer is a major cause of cancer-related death,with a 5-year overall survival rate being below 5%.The main causes of poor prognosis in pancreatic cancer include easy metastasis,high recurrence rate,and robust drug resistance.Gemcitabine is a first-line drug for patients with unresectable pancreatic cancer.However,due to drug resistance,the clinical effect is not satisfactory.ADAM28 is reported as a tumor promoter in some cancers,but its role in pancreatic cancer and gemcitabine chemoresistance in pancreatic cancer has not been elucidated.AIM To identify if ADAM28 can act as an important target to reverse the gemcitabine drug resistance in pancreatic cancer.METHODS RNA-sequence analysis was applied to explore the potential targets involved in the gemcitabine of pancreatic cancer.SW1990 pancreatic cancer cells were treated with an increased dose of gemcitabine,and the mRNA levels of ADAM28 were evaluated by RT-PCR.The protein and mRNA levels of ADAM28 were confirmed in the gemcitabine resistant and parallel SW1990 cells.The ADAM28 expression was also assessed in TCGA and GEO databases,and the results were confirmed in the collected tumor and adjacent normal tissues.The overall survival(OS)rate and relapse-free survival(RFS)rate of pancreatic cancer patients with high ADAM28 level and low ADAM28 level in TCGA were evaluated with Kaplan-Meier Plotter.Furthermore,the OS rate was calculated in pancreatic cancer patients with high tumor mutation burden(TMB)and low TMB.CCK-8 assay was used to examine the effect of ADAM28 on the viability of SW1990 cells.The ADAM28 and its co-expressed genes were analyzed in the cBioPortal for cancer genomics and subjected to GSEA pathway analysis.The correlations of ADAM28 with GSTP1,ABCC1,GSTM4,and BCL2 were analyzed based on TCGA data on pancreatic cancer.RESULTS RNA-sequence analysis identified that ADAM28 was overexpressed in gemcitabine-resistant cells,and gemcitabine treatment could induce the expression of ADAM28.The mRNA and protein levels of ADAM28 were elevated in gemcitabine-resistant SW1990 cells compared with parallel cells.Also,the expression of ADAM28 was upregulated in pancreatic tumor tissues against normal pancreatic tissues.Notably,ADAM28 was highly expressed in the classical type than in the basal tumor type.Furthermore,the high expression of ADAM28 was associated with low OS and RFS rates.Interestingly,the high levels of ADAM28 was associated with a significantly lower OS rate in the high TMB patients,but not in the low TMB patients.Moreover,overexpression of ADAM28 could reduce the cell viability inhibition by gemcitabine,and knockdown of ADAM28 could enhance the proliferation inhibition by gemcitabine.The GSEA analysis showed that ADAM28 was related to the regulation of drug metabolism,and ADAM28 was significantly positively correlated with GSTP1,ABCC1,GSTM4,and BCL2.CONCLUSION This study demonstrates that ADAM28 is overexpressed in pancreatic cancer,and closely involved in the regulation of gemcitabine resistance.Overexpression of ADAM28 is a novel prognostic biomarker in pancreatic cancer. 展开更多
关键词 ADAM28 DRUG RESISTANCE OVEREXPRESSION poor prognosis DRUG metabolism GEMCITABINE
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Effect of Die Wall Lubrication on Warm Compaction Powder Metallurgy 被引量:13
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作者 LI Yuan-yuan, NGAI Tungwai Leo, ZHANG Da-tong, LONG Yan, XIA Wei (College of Mechanical Engineering, South China University of Technology, Guangzhou 510640, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期45-46,共2页
Die wall lubrication was applied on warm compaction powder metallurgy in hope to reduce the concentration level of the admixed lubricant since lubricant is harmful to the mechanical property of the sintered materials.... Die wall lubrication was applied on warm compaction powder metallurgy in hope to reduce the concentration level of the admixed lubricant since lubricant is harmful to the mechanical property of the sintered materials. Iron-based samples were prepared by die wall lubricated warm compaction at 135 ℃ and 175 ℃, using polytetrafluoroethylene (PTFE) emulsion as die wall lubricant. A compacting pressure of 700 MPa and 550 MPa were used. The admixed lubricant concentration ranging from 0 to 0.6 wt.% was used in this study. Compared with non-die wall lubricated samples, the die wall lubricated samples have higher green densities. Results show that in addition to the decrease in ejection forces, green density of the compacts increased linearly with the decrease in admixed lubricant content. Mechanical property of the sintered compacts increase sharply when the admixed lubricant concentration reduced to 0.125 wt.% or less. Ejection force data indicated that samples with die wall lubrication show lower ejection forces when compared with samples without die wall lubrication. No scoring was observed in all experiments even for samples contain no admixed lubricant. Our results indicated that under experimental condition used in this study, no matter at which compaction pressure, compaction temperature, graphite and lubricant contents in the powder the die wall lubricated warm compaction would give the highest green density and lowest ejection force. It can be concluded that combination of die wall lubrication and warm compaction can provide P/M products with higher density and better quality. It is a feasible way to produce high performance P/M parts if suitable die wall lubrication system was applied. 展开更多
关键词 warm compaction die wall lubrication powder metallurgy
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Multi-factor analysis of initial poor graft function after orthotopic liver transplantation 被引量:12
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作者 Chen, Hao Peng, Cheng-Hong +5 位作者 Shen, Bai-Yong Deng, Xia-Xing Shen, Chuan Xie, Jun-Jie Dong, Wei Li, Hong-Wei 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2007年第2期141-146,共6页
BACKGROUND: In the early period of orthotopic liver transplantation (OLT), initial poor graft function (IPGF) is one of the complications which leads to primary graft non-function (PGNF) in serious cases. This study s... BACKGROUND: In the early period of orthotopic liver transplantation (OLT), initial poor graft function (IPGF) is one of the complications which leads to primary graft non-function (PGNF) in serious cases. This study set out to establish the clinical risk factors resulting in IPGF after OLT. METHODS: Eighty cases of OLT were analyzed. The IPGF group consisted of patients with alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) above 1500 IU/L within 72 hours after OLT, while those in the non-IPGF group had values below 1500 IU/L. Recipient-associated factors before OLT analyzed were age, sex, primary liver disease and Child-Pugh classification; factors analyzed within the peri-operative period were non-heart beating time (NHBT), cold ischemia time (CIT), rewarming ischemic time (RWIT), liver biopsy at the end of cold ischemia; and factors analyzed within 72 hours after OLT were ALT and/or AST values. A logistic regression model was applied to filter the possible factors resulting in IPGF. RESULTS: Donor NHBT, CIT and RWIT were significantly longer in the IPGF group than in the non-IPGF group; in the logistic regression model, NHBT was the risk factor leading to IPGF (P < 0.05), while CIT and RWIT were possible risk factors. In one case in the IPGF group, PGNF appeared with moderate hepatic steatosis. CONCLUSIONS: Longer NHBT is an important risk factor leading to IPGF, while serious steatosis in the donor liver, CIT and RWIT are potential risk factors. 展开更多
关键词 orthotopic liver transplantation poor liver function multi-factor analysis
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