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Synthesis of bacillamide 3 and its analogue

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Chinese Chemical Letters 2009年第10期20卷 1195-1197页

作者： Duo Li Hai shen Yang qing Cui shen Jie Mao Xiao Hua Xu State Key Laboratory of Elemento-Organic Chemistry Nankai University Tlanjin 300071 China

The bacillamide 1 is a new algaecide from the marine bacterium Bacillus sp. SY-1. Its analogues bacillamide 3 and alkaloid 4 were firstly synthesized effectively from D-alanine. The key step was a coupling reaction via the mixed anhydride. All structures were confirmed by IH NMR and 13C NMR. The final compounds were confirmed by 1H NMR, 13C NMR and HRMS and the results are consistent with the reported natural products.

关键词： Bacillamide Thiazole rings Tryptamide Synthesis

Using Pre-Estimate with Feedback for Adaptation Web Server QoS Guarantee

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 256-262页

作者： WANG Li shen qing-guo Institute of Communications Engineering PLA University of Science and Technology Nanjing 210007 Jiangsu China

The heterogeneity in the communicating terminals needs to he handled through software-supported adaptation, The real-time dynamical adaptation brings the system more time cost unavoidably. In this paper, we propose QoS pre-estimation for user admission control and system load control. Feedback acts as adjuster of the input parameters of the pre-estimate module. We present tests results to evaluate our approach, The test results show that our service quality control mechanism is effective.

关键词： pre-estimate feedback control QoS adaptation system

Urban Spatial Restructuring in Transitional Economy——Changing Land Use Pattern in Shanghai

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Chinese Geographical Science 2007年第1期17卷 19-27页

作者： XU Jiangang LIAO Banggu shen qing ZHANG Feng MEI Anxin Department of Urban and Resources Sciences Nanjing University Nanjing 210093 China Urban Studies and Planning Program University of Maryland College Park MD 20742 USA Department of Geography East China Normal University Shanghai 200062 China

For almost three decades, China has been undergoing significant transition from a planned economy to a market economy. Fast-paced economic growth and urbanization, interacting with market-oriented reforms in land re- sources allocation, have caused profound spatial restructuring of Chinese cities. This paper examines urban expansion and land use reconfiguration in Shanghai’s central city from 1979 to 2002, with a special focus on the effect of the adoption of the land-leasing system in 1988. The empirical research, which employs GIS-based spatial analysis tech- niques to explore land use data for multiple years, indicates fundamental changes in the spatial characteristics of urban development in Shanghai after this important land policy reform.

关键词： land use pattern land policy GIS Shanghai China

Thermo-hydro-mechanical-chemical(THMC)coupling fracture criterion of brittle rock

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Transactions of Nonferrous Metals Society of China 2021年第9期31卷 2823-2835页

作者： Wei YI Qiu-hua RAO Zhuo LI Dong-liang SUN qing-qing shen School of Civil Engineering Central South UniversityChangsha 410075China

Based on analysis of thermo-hydro-mechanical-chemical(THMC)coupling mechanism for brittle rock,THMC coupling indicator in terms of rock porosity was introduced to represent the influencing degree of THMC coupling field on stress field in order to establish THMC coupling fracture criterion.A novel real-time measurement method of permeability(related to porosity)was proposed to determine the THMC coupling indicator,and self-designed THMC coupling tests and scanning electron microscope tests were conducted on pre-cracked red sandstone specimens to study the macroscopic and microscopic fracture *** results show that the higher the hydraulic pressure is,the smaller the crack initiation load is and the easier the Mode I fracture *** results are in good agreement with prediction results(crack initiation load and angle,and fracture mode),which can verify the effectiveness of the newly established THMC coupling fracture *** new fracture criterion can be also further extended to predict THMC coupling fracture of multi-crack problem.

关键词： THMC coupling fracture criterion THMC coupling indicator brittle rock

High-speed maneuvering target detection approach based on joint RFT and keystone transform

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Science China(Information Sciences) 2013年第6期56卷 93-105页

作者： TIAN Jing CUI Wei shen qing WEI ZiXiang WU SiLiang Radar Research Laboratory Beijing Institute of Technology

Increasing the integration time is an effective method to improve small maneuvering target detection performance in radar ***,range migration and Doppler spread caused by maneuvering target motion during the integration time make it difficult to improve the coherent accumulation of target's energy and detection *** this study,a new method based on Radon Fourier transform(RFT) and keystone transform(KT) for high-speed maneuvering target detection is *** proposed algorithm utilizes second-order KT to correct the range curvature,and the improved dechirping method to compensate for the Doppler *** is then used to correct the range walk for target coherent *** method is capable of correcting the range migration and the time-varied Doppler frequency of the target without knowing its velocity and *** advantage of the proposed method is that it can increase the coherent integration time and improve detection performance under the condition of Doppler frequency *** with the second-order RFT algorithm,the computational burden of the proposed method is greatly reduced under the premise that the two methods have similar estimation accuracy of range,velocity and *** experiments demonstrate the validity of the proposed algorithm.

关键词： high-speed maneuvering target range migration correction Doppler spread coherent integration keystone transform

基于TiO_(2)/KCC-1固相萃取的亲水作用超高效液相色谱-串联质谱法测定南极磷虾磷脂

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食品科学 2024年第15期45卷 168-177页

作者：张欣彤唐光治沈清雷敏谭舒萍林碧玲周瑞淇梁秀碧郭莲仙李林秋广东医科大学海洋医药研究院南海海洋生物医药资源研发公共服务平台广东湛江524023 广东医科大学公共卫生学院东莞市卫生检验与检疫重点实验室广东东莞523808 浙江工商大学海洋食品研究院浙江杭州310012 上海爱博才思分析仪器贸易有限公司上海200335

以自制钛基树枝状纤维形SiO_(2)(TiO_(2)/KCC-1)纳米材料作为固相萃取(solid phase extraction,SPE)填料对南极磷虾中的磷脂进行纯化,采用亲水色谱柱结合超高效液相色谱串联质谱法进行磷脂组学分析。选取南极磷虾中最主要的4类磷脂(磷... 详细信息

以自制钛基树枝状纤维形SiO_(2)(TiO_(2)/KCC-1)纳米材料作为固相萃取(solid phase extraction,SPE)填料对南极磷虾中的磷脂进行纯化,采用亲水色谱柱结合超高效液相色谱串联质谱法进行磷脂组学分析。选取南极磷虾中最主要的4类磷脂(磷脂酰胆碱(phosphatidylcholines,PC)、磷脂酰乙醇胺(phosphatidyl ethanolamine,PE)、磷脂酰丝氨酸(phosphatidylserine,PS)、磷脂酰肌醇(phosphatidylinositol,PI))作为研究对象。结果显示,在最优条件下共检测到291种磷脂,比已报道的方法多近1倍。在这些磷脂中,含有单不饱和脂肪酸链的磷脂占总磷脂含量的54.73%,含有多不饱和脂肪酸链的磷脂占总磷脂含量的26.17%。南极磷虾中共检出PC 75种、PE 120种、PI 54种、PS 42种。其中PC(40:6)(41.63%)、PE(36:0)(39.77%)、PI(38:3)(80.05%)、PS(36:1)(81.62%)在4类磷脂中的含量最高。多元统计分析结果显示,SPE处理前后磷脂种类有明显差异,Ti O_(2)/KCC-1材料对磷脂的富集效果显著,特别是对PC(18:0/18:0)、PE(16:0/18:1)、PI(16:0/18:2)等富集作用明显。PC、PE和PS的检出限均为0.05μg/g,PI的检出限为0.01μg/g,4种磷脂的相对标准偏差在0.89%~5.05%之间,回收率在87%~112%之间。该方法专一性强、提取效率高、灵敏度和精密度高、准确度好,在生物样本中磷脂的提取、纯化及其检测方面具有广阔的应用前景。

关键词：钛基树枝状纤维形SiO_(2) 固相萃取亲水作用超高效液相色谱-串联质谱法南极磷虾磷脂

Interacting mechanism and initiation prediction of multiple cracks

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Transactions of Nonferrous Metals Society of China 2021年第3期31卷 779-791页

作者： qing-qing shen Qiu-hua RAO Zhuo LI Wei YI Dong-liang SUN School of Civil Engineering Central South UniversityChangsha 410075China

The maximum Mode Ⅰ and Mode Ⅱ stress intensity factors(SIFs), KI,kmax(θ) and KII,kmax(θ)(0°<θ<360°), of inclined parallel multi-crack varying with relative positions(including horizontal and vertical spacings) are calculated by the complex function and integration method to analyze their interacting mechanism and determine the strengthening and weakening zone of SIFs. The multi-crack initiation criterion is established based on the ratio of maximum tension-shear SIF to predict crack initiation angle, load, and mechanism. The results show that multi-crack always initiates in Mode Ⅰ and the vertical spacing is better not to be times of half crack-length for crack-arrest, which is in good agreement with test results of the red-sandstone cube specimens with three parallel cracks under uniaxial compression. This can prove the validity of the multi-crack initiation criterion.

关键词： interaction mechanism multi-crack initiation criterion initiation prediction multiple cracks stress intensity factor

Effect of L-cysteine on remote organ injury in rats with severe acute pancreatitis induced by bile-pancreatic duct obstruction

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Hepatobiliary & Pancreatic Diseases International 2013年第4期12卷 428-435页

作者： Li-Juan Yang Rong Wan Jia-qing shen Jie shen Xing-Peng Wang Department of Gastroenterology Shanghai First People's Hospital Shanghai Jiaotong University Shanghai Key Laboratory of Pancreatic Diseases Shanghai First People's Hospital Shanghai Jiaotong University Department of Gastroenterology Shanghai Tenth People's Hospital Tongji University School of Medicine Department of Gastroenterology Shanghai Tenth People's Hospital Tongji University School of Medicine

BACKGROUND: Remote organ failure occurs in cases of acute pancreatitis (AP); however, the reports on AP induced by pancreatic duct obstruction are rare. In this study we determined the effect of L-cysteine on pancreaticobiliary inflammation and remote organ damage in rats after pancreaticobiliary duct ligation (PBDL). METHODS: AP was induced by PBDL in rats with 5/0 silk Sixty rats were randomly divided into 4 groups. Groups A and B were sham-operated groups that received injections of saline or L-cysteine (10 mg/kg) intraperitoneally (15 rats in each group). Groups C and D were PBDL groups that received injections of saline or L-cysteine (10 mg/kg) intraperitoneally (15 rats in each group). The tissue samples of the pancreas and remote organs such as the lung, liver, intestine and kidney were subsequently examined for pathological changes under a light microscope. The samples were also stored for the determination of malondialdehyde and glutathione levels. Blood urea nitrogen (BUN), plasma amylase, ALT and AST levels were determined spectrophotometrically using an automated analyzer. Also, we evaluated the effect of L-cysteine on remote organ injury in rats with AP induced by retrograde infusion of 3.5% sodium taurocholate (NaTc) into the bile-pancreatic duct. RESULTS: Varying degrees of injury in the pancreas, lung, liver intestine and kidney were observed in the rats 24 hours after PBDL. The severity of injury to the lung, liver and intestine was attenuated, while injury status was not changed significantly in the pancreas and kidney after L-cysteine treatment. Oxidativestress was also affected by L-cysteine in PBDL-treated rats. The concentration of tissue malondialdehyde decreased in the pancreas and remote organs of PBDL and L-cysteine administrated rats, and the concentration of glutathione increased more significantly than that of the model control group. However, L-cysteine administration reduced the severity of injury in remote organs but not in the pancre

关键词： pancreatitis oxidative stress lung injury liver failure animal models pathological changes

运动联合呼吸训练在慢性阻塞性肺疾病患者康复治疗中的应用效果

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中国社区医师 2024年第21期40卷 144-146页

作者：沈清陈淑琴朱文婷樊琦沈宇峰上海市静安区静安寺街道社区卫生服务中心上海200040

目的:探讨运动联合呼吸训练在慢性阻塞性肺疾病患者康复治疗中的应用效果。方法:选取2022年10月—2023年4月上海市静安寺街道社区卫生服务中心收治的慢性阻塞性肺疾病患者72例作为研究对象,采用随机数字表法分为对照组和试验组,各36例... 详细信息

目的:探讨运动联合呼吸训练在慢性阻塞性肺疾病患者康复治疗中的应用效果。方法:选取2022年10月—2023年4月上海市静安寺街道社区卫生服务中心收治的慢性阻塞性肺疾病患者72例作为研究对象,采用随机数字表法分为对照组和试验组,各36例。对照组采用常规康复治疗,试验组在对照组基础上采用运动联合呼吸训练治疗。比较两组肺功能指标、6 min步行距离、呼吸困难程度、生活质量评分及治疗效果。结果:治疗前,两组用力肺活量(FVC)和第1秒用力呼气容积(FEV_(1))、FEV1/FVC比较,差异无统计学意义(P>0.05);治疗后,两组FVC、FEV_(1)、FEV_(1)/FVC均高于治疗前,试验组高于对照组(P0.05);治疗后,两组mMRC和SGRQ评分均低于治疗前,且试验组低于对照组(P<0.05)。试验组治疗总有效率高于对照组(P<0.001)。结论:运动联合呼吸训练在慢性阻塞性肺疾病患者康复治疗中的应用效果较好,能够改善患者呼吸困难症状,促进肺功能恢复,提升其生活质量。

关键词：慢性阻塞性肺疾病运动呼吸训练肺功能