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life Prediction Based on Transient Dynamics Analysis of Van Semi-trailer with Air Suspension System

Chinese Journal of Mechanical Engineering 2011年第3期24卷 372-379页

作者： li liang SONG jian HE lin ZHANG Mengjun li Hongzhi State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing 100084 China

The early fatigue damage in the van-body of the semi-trailer is often caused by the unique mechanical characteristics and the dynamic impact of the *** traditional finite element method with static strength analysis cannot support the fatigue design of van-body;thus,the dynamics analysis should be adopted for the endurance *** accurate dynamics model to describe the transient impacts of all kinds of uneven road and the proper system transfer functions to calculate the load transfer effects from tire to van-body are two critical factors for transient dynamics *** order to evaluate the dynamic performance,the dynamics model of the trailer with the air suspension is brought *** the analysis method of the power spectral density （PSD） is set up to study the transient responses of the road dynamic *** transient responses transferred from axles to van-body are calculated,such as dynamic stress,dynamic RMS acceleration,and dynamic load *** on the above dynamic responses,the fatigue life of van-body is predicted with the finite element analysis （FEA） *** the test parameters of the trailer with air suspension,the simulation system with Matlab/Simulink is constructed to describe the dynamic responses of the impacts of the tested PSD of the vehicle axles,and then the fatigue life is predicted with FEA *** simulated results show that the vibration level of the van-body with air suspension is reduced and the fatigue life is *** real vehicle tests on different roads are carried out,and the test results validate the accuracy of the simulation *** proposed fatigue life prediction method is effective for the virtual design of auto-body.

关键词： van-body air suspension system transient dynamics power spectral density (PSD) life prediction

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Road Friction Estimation under Complicated Maneuver Conditions for Active Yaw Control

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Chinese Journal of Mechanical Engineering 2009年第4期22卷 514-520页

作者： li liang li Hongzhi SONG jian YANG Cai WU Hao The State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing 100084 China

Road friction coefficient is a key factor for the stability control of the vehicle dynamics in the critical conditions. Obviously the vehicle dynamics stability control systems, including the anti-lock brake system（ABS）, the traction control system（TCS）, and the active yaw control（AYC） system, need the accurate tire and road friction information. However, the simplified method based on the linear tire and vehicle model could not obtain the accurate road friction coefficient for the complicated maneuver of the vehicle. Because the active braking control mode of AYC is different from that of ABS, the road friction coefficient cannot be estimated only with the dynamics states of the tire. With the related dynamics states measured by the sensors of AYC, a comprehensive strategy of the road friction estimation for the active yaw control is brought forward with the sensor fusion technique. Firstly, the variations of the dynamics characteristics of vehicle and tire, and the stability control mode in the steering process are considered, and then the proper road friction estimation methods are brought forward according to the vehicle maneuver process. In the steering maneuver without braking, the comprehensive road friction from the four wheels may be estimated based on the multi-sensor signal fusion method. The estimated values of the road friction reflect the road friction characteristic. When the active brake involved, the road friction coefficient of the braked wheel may be estimated based on the brake pressure and tire forces, the estimated values reflect the road friction between the braked wheel and the road. So the optimal control of the wheel slip rate may be obtained according to the road friction coefficient. The methods proposed in the paper are integrated into the real time controller of AYC, which is matched onto the test vehicle. The ground tests validate the accuracy of the proposed method under the complicated maneuver conditions.

关键词： active yaw control road friction coefficient estimation sensor fusion

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Cyanidation of gold clay ore containing arsenic and manganese

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 132-136页

作者： Yu-liang li jian liu Wei-sheng Guan School of Environmental Science and Engineering Chang＇an University Xi＇an 710054 China

The extraction process of gold and silver from the gold clay ore containing arsenic and manganese was *** the conventional technique,the leaching rates of gold and silver are 78.23%and 49.02%,*** eliminate the negative effects of arsenic and manganese on cyanidation and increase the gold and silver leaching rates,a novel catalyst was *** content of the catalyst used in the process was 8 g per 500 g org sample,the sample size was 60μm and the pH value was kept between 10 and *** with the catalyst for 3-5 h under certain conditions,the gold leaching rate increased to over 90%and the silver leaching rate increased to 80%-90%.The catalyst can effectively liberate gold and silver from the enclosure of arsenic and manganese and the industrial experiment has great significance to the development and utilization of the gold clay ore containing arsenic and manganese.

关键词： gold ore cyanidation catalyst gold silver leaching rate

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Intra-portal transplantation of bone marrow stromal cells ameliorates liver fibrosis in mice

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Hepatobiliary & Pancreatic Diseases International 2008年第3期7卷 264-270页

作者： Zheng, Jin-Fang liang, li-jian Peoples Hosp Hainan Prov Dept Hepatobiliary Surg Haikou 570311 Peoples R China Sun Yat Sen Univ Affiliated Hosp 1 Dept Hepatobiliary Surg Guangzhou 510080 Peoples R China

BACKGROUND: Bone marrow cells can differentiate into hepatocytes in a suitable microenvironment. This study was undertaken to investigate the effects of transplanted bone marrow stromal cells (BMSCs) on liver fibrosis in mice. METHODS: BMSCs were harvested and cultured from male BALB/c mice, then transplanted into female syngenic BALB/c mice via the portal vein. After partial hepatectomy, diethylnitrosamine (DEN) was administered to induce liver fibrosis. Controls received BMSCs and non-supplemented drinking water, the model group received DEN with their water, and the experimental group received BMSCs and DEN. Mice were killed after 3 months, and ALT, AST, hyaluronic acid (HA), and laminin (LN) in serum and hydroxyproline (Hyp) in the liver were assessed. Alpha-smooth muscle actin (alpha-SMA) in the liver was assessed by immunohistochemistry. Bone marrow-derived hepatocytes were identified by fluorescent in situ hybridization (FISH) in liver sections. RESULTS: BMSCs were shown to differentiate into hepatocyte-like phenotypes after hepatocyte growth factor treatment in vitro. Serum ALT, AST, HA, and LN were markedly reduced by transplanted BMSCs. liver Hyp content and alpha-SMA staining in mice receiving BMSCs were lower than in the model group, consistent with altered liver pathology. FISH analysis revealed the presence of donor-derived hepatocytes in the injured liver after cross-gender mouse BMSC transplantation. After three months, about 10% of cells in the injured liver were bone marrow-derived. CONCLUSION: BMSCs transplanted via the portal vein can convert into hepatocytes to repair liver injury induced by DEN, restore liver function, and reduce liver fibrosis.

关键词： bone marrow stromal cell hepatocyte differentiation cell therapy liver fibrosis

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Novel Synthesis of Sol-gel Derived Nanosized Mullite Powder

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Chinese Journal of Aeronautics 2006年第B12期19卷 71-73页

作者： liang Long li jian-bao liN Hong GUO Gang-feng HE Ming-sheng State Key Lab of New Ceramics and Fine Processing Dept of Materials Science and Engineering Tsinghua University Beijing 100084 China

Using hydrous aluminum chloride （AlCl3·6H2O） and silicon ethoxide （Si （OC2H5）4） as raw materials, a kind of nano-sized mullite powder was synthesized with the sol-gel process at the medium calcination temperature. The microstructures of the alumina-silica binary aerogel and calcined nano-sized materials were investigated by means of thermogravimetry-differential thermal analysis （TG-DTA）, scanning electron microscopy （SEM） and X-ray diffractometer （XRD）. The results show that the mullitization of Al2O3-SiO2 in gel starts from about 1 000℃ and its formation ofmullite takes place in the range of 1 100℃-1 250 ℃. The size of the nano-sized mullite powder calcined at 1 250 ℃ is measured to be about 30 nm.

关键词： mullite sol-gel synthesis temperature

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Pancreatic head carcinoma:clinical analysis of 189 cases

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Hepatobiliary & Pancreatic Diseases International 2009年第1期8卷 79-84页

作者： Hua, Yun-Peng liang, li-jian Peng, Bao-Gang li, Shao-Qiang Huang, Jie-Fu Sun Yat Sen Univ Affiliated Hosp 1 Dept Hepatobiliary Surg Guangzhou 510080 Guangdong Peoples R China

BACKGROUND: Pancreatic cancer is a lethal disease with an increasing incidence. We retrospectively reviewed the clinical data on diagnosis and treatment of pancreatic head carcinoma, and analyzed the factors affecting prognosis of the disease. METHODS: The data of 189 patients with pancreatic head carcinoma treated from September 1, 1995 to August 31, 2005 were reviewed retrospectively. Ninety-four patients treated from September 1, 2000 to August 31, 2005 were followed up in April 2008. The median survival time (MST) and 1- to 5-year cumulative survival rates of the patients were calculated by the life table method and the Kaplan-Meier method. Cox regression was used to screen out significant risk factors. RESULTS: 96.9% of the patients were more than 40 years old, and the male/female ratio was 1.63. The detection rate of transabdominal ultrasonography (US), computed tomography (CT), endoscopic ultrasonography (EUS), and serum tumor marker CA19-9 were 82.0%, 93.1%, 94.7% and 79.8%, respectively. The MST of patients with pancreatic head carcinoma was 360 +/- 60 days. The 1- to 5-year cumulative survival rates were 50.0%, 19.2%, 12.1%, 9.4% and 4.7%, respectively. However, patients with unresectable tumor survived for a shorter time (183 +/- 18 days). Their 1- to 2-year cumulative survival rates were 28.3% and 0.0%. Cox regression analysis showed that in pancreatic head carcinoma, the independent predictors for prognosis included tumor size, invasion of the superior mesenteric vessel, and radical resection. The MST of patients with pancreatic head carcinoma after radical resection was 510 days, significantly longer than that of patients undergoing non-specific treatment and palliative therapy (225 days). In addition, patients with slight jaundice survived for the longest time (533 +/- 51 days), compared with patients with severe jaundice (236 +/- 43 days) and without jaundice (392 +/- 109 days). CONCLUSIONS: Pancreatic head carcinoma is easily misdiagnosed, and is us

关键词： pancreatic head carcinoma surgical procedure diagnosis prognosis

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Surgical resection for hepatoportal bile duct cancer

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World Journal of Gastroenterology 1999年第2期5卷 40-43页

作者： HE Xiao Shun, HUANG Jie Fu, liang li jian, LU Ming De and CAO Xiu Hu

AIM To discuss the effect of surgical procedures on the prognosis of patients of bile duct cancer and their *** A retrospective analysis was made for 52 cases of hepatoportal bile duct cancer treated from January 1991 to December 1996. All the cases were classified according to the modified Bismuth-Corlettle system and received appropriate operation. Therapeutic effects were evaluated on the basis of their survival rates, jaundice elimination, comfort index, operative mortality and *** Seventeen cases received surgical resection (32.7%). The survival rate was 71.4%, 35.7% and 10.4% for one, two and three years respectively, and was 30%, 16.8% and 0% for those with drainage (P＜0.05). The mortality rate was 6.0% for the drainage group and 5.9% for the resection group (P＞0.05). Of the 17 resected patients, 8 (47.1%) had curative resection and 9 (52.9%) noncurative resection. Their mean survival time was 21.1 months and 7.5 months respectively (P＜0.05).CONCLUSION Proper surgical procedure should be used on the basis of the local and general conditions of the patients, and aggressive resection with or without liver resection is a valid procedure for the treatment of hepatoportal bile duct cancer and can significantly improve the prognosis of patients.

关键词： biliary tract neoplasms/surgery prognosis hepatic portal

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Long-term outcome and prognostic factors of intrahepatic cholangiocarcinoma

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Chinese Medical Journal 2009年第19期122卷 2286-2291页

作者： li Shao-qiang liang li-jian HUA Yun-peng PENG Bao-gang HE Qiang LU Ming-de CHEN Dong Department of Hepatobiliary Surgery the First Affiliated Hospital Sun Yat-sen University Guangzhou Guangdong 510080 China

Background The management of intrahepatic cholangiocarcinoma （ICC） remains a challenge due to poor prognosis. The aim of this study was to summarize the surgical management experience in recent 10 years and to identify the influencing factors related to outcome of patients with ICC in a single hepatobiliary center. Methods From January 1995 to June 2005, 136 patients with ICC undergoing surgery were reviewed retrospectively. Survival rates of patients were calculated using the Kaplan-Meier method and compared by using the log-rank test. The prognostic factors were identified by the Cox regression model. Results Seventy-nine of 136 patients underwent resection, and 65 of 79 patients were curative （R0）. The surgical mortality was 2.2%. The 1-, 3- and 5-year survival rates of patients undergoing R0 resection were 72.1%, 35.6% and 20.1% respectively, which were significantly longer than those who underwent palliative resection and exploration, respectively （P 〈0.01）. At stage IV of the disease, 10 patients who underwent aggressive curative resection achieved a better median survival than those （n=12） without resection （14 months vs 3 months, P 〈0.001）. The independent prognostic factors of the whole group were TNM stage （OR, 2.013, P=0.008） and curative resection （OR, 2.957, P=0.003）. Higher TNM stage （OR, 1.894, P=0.004） and lymph node metastasis （OR, 4.248, P=0.005） linked to poor prognosis after R0 resection. For patients without lymph node metastasis, the median survival of those who underwent regional lymphadenectomy was comparable with those who did not （18 months vs 22 months, P=0.817）. Conclusions R0 resection is mandatory for ICC patient to achieve long-term survival. Aggressive resection benefits for selected patients with local advanced disease. Higher TNM stage and lymph node metastasis were poor prognostic factors for ICC patients after R0 resection.

关键词： cholangiocarcinoma intrahepatic prognosis

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Simulation of Induction Heating Process of Continuous Casting Slab

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Computer Aided Drafting,Design and Manufacturing 2007年第1期17卷 54-59页

作者： liU Hao CHEN li-liang ZHOU jian-xin liAO Dun-ming State Key Laboratory of Material Processing and Die ＆ Mould Technology Huazhong University of Science and Technology Wuhan 430074 China

Induction heating of steel in continuous casting/rolling process is an important means to reduce energy consumption, decrease cost and improve efficiency, thus becoming an attractive research direction. A mathematical model with Finite Difference Method （FDM） was developed to describe the electromagnetic field and predict the temperature distribution in the steel slab for the whole induction heating process. To validate feasibility of the model, computational results were compared with the ANSYS simulation results. According to the comparing results, the temperature distributions of the slab cast under different technical parameters were investigated, which may provide useful information to optimize the parameters of technology in heating process.

关键词： induction heating finite difference method finite element method ANSYS temperature distribution

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A study of the ameliorating effects of carnitine on hepatic steatosis induced by total parenteral nutrition in rats

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World Journal of Gastroenterology 1999年第4期5卷 40-43页

作者： liang li jian, YIN Xiao Yu, LUO Shi Min, ZHENG Jin Fang, LU Ming De and HUANG Jie Fu

AIM To investigate the effects of carnitine on ameliorating hepatic steatosis induced by total parenteral nutrition (TPN) in animal model. METHODS Eighteen normal Wistar rats and 19 cirrhotic Wistar rats induced by carbon tetrachloride were randomly divided into three groups, i.e., free access to food and drink (group A), TPN (group B) and TPN+carnitine (group C) for one week, respectively. Hepatic function, histology and its fat content were determined on the 7th day. RESULTS Hepatic triglyceride (TG) and cholesterol (CHO) contents were significantly higher in groups B and C than in group A, and significantly lower in group C than in group B in both normal and cirrhotic rats (all P liorate hepatic steatosis associated with TPN in both non cirrhotic and cirrhotic rats.

关键词： carnitine hepatic steatosis total parenteral nutrition rats

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