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低阶煤转化机理及计算化学方法在探究中的应用

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煤炭与化工 2024年第2期47卷 143-148,156页

作者：白蛟宣鲁婷李光跃华北理工大学化学工程学院河北唐山063210

褐煤等储量丰富的低阶煤可以通过热解、气化、液化等低阶煤提质转化技术来制备高附加值化学品和优质能源。计算化学方法在低阶煤转化技术的机理探究及工艺优化方面至关重要。对低阶煤转化机理的研究现状进行归纳,综述了计算化学如分子... 详细信息

褐煤等储量丰富的低阶煤可以通过热解、气化、液化等低阶煤提质转化技术来制备高附加值化学品和优质能源。计算化学方法在低阶煤转化技术的机理探究及工艺优化方面至关重要。对低阶煤转化机理的研究现状进行归纳,综述了计算化学如分子动力学模拟和密度泛函理论在低阶煤转化机理研究中的应用,并提出了计算化学方法在低阶煤转化机理探究中可行的优化方向。

关键词：低阶煤提质计算化学反应力场分子动力学模拟密度泛函理论

On the Range of the Common Cycle Time in a Road Network

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Journal of Harbin Institute of Technology(New Series) 2015年第6期22卷 31-36页

作者： ting lu Marko Wlki Peter Wagner Institute of Transportation Systems German Aerospace Center (DLR) Faculty of Maritime and Transportation Ningbo University

In a coordinated road network,the optimal common cycle time is determined by evaluating the performance of the network in the given range of cycles. Normally,this range is determined by users 'experience. And a large range of common cycle time,e. g. [30,200] is chosen,which requires long computation time. This study considers that the optimal common cycle time ranges between the minimal and maximal value of intersections' individual optimal cycle time. It is proved mathematically from the convexity condition,that the delay of the network and each individual intersection are convex functions of the cycle time according to Webster delay model. Finally,2 000 random cases for the network composed of two intersections and of eight intersections are created to underline the proposed conclusions. The results of all cases confirm the validity,and show up to 90% improvement in computation time to compare with experience range. The signal optimization tool,Synchro,is also used to validate the conclusion by 50 random cases. The results confirm reliability further.

关键词： common cycle traffic signal optimization convexity Webster model

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全缘铁线莲种子休眠特性及破眠方法研究

中国野生植物资源 2024年第6期43卷 44-50页

作者：周睿陆婷刘爱民新疆农业大学林学与风景园林学院新疆乌鲁木齐830052 新疆哈巴河县林业局新疆阿勒泰836700

目的:全缘铁线莲(Clematis integrifolia L.)是铁线莲属直立多年生草本或亚灌木,有很高的观赏价值,了解种子休眠特性及破眠方法可为其引种驯化和园林应用提供科学依据。方法:以全缘铁线莲种子为研究材料,通过纸培法探究控制条件下种子... 详细信息

目的:全缘铁线莲(Clematis integrifolia L.)是铁线莲属直立多年生草本或亚灌木,有很高的观赏价值,了解种子休眠特性及破眠方法可为其引种驯化和园林应用提供科学依据。方法:以全缘铁线莲种子为研究材料,通过纸培法探究控制条件下种子休眠及萌发的生物学特性。结果:果实形态成熟时种子尚不具备发芽能力,种子生活力为86.33%±2.87%,种皮(包括瘦果果皮)透水性良好,种胚无吸水障碍。种子浸取液对小白菜种子发芽及幼苗生长有显著抑制作用。果实形态成熟时种胚发育尚不完全,低温层积能促进种胚发育。低温层积90 d可将种子发芽率提高到73.33%±4.71%。使用200 mg·L-1赤霉素浸种24 h可使种子发芽率提高到61.11%±5.67%。结论:全缘铁线莲种子休眠是由于萌发抑制物和种胚分化不完全而导致的形态生理休眠,播种前将种子低温层积90 d或使用200 mg·L-1赤霉素浸种24 h可以有效打破种子的休眠从而促进种子萌发。

关键词：全缘铁线莲种子休眠萌发抑制物低温层积赤霉素

LncRNA GAS5 enhances tumor stem cell-like medicated sensitivity of paclitaxel and inhibits epithelial-to-mesenchymal transition by targeting the miR-18a-5p/STK4 pathway in prostate cancer

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Asian Journal of Andrology 2022年第6期24卷 643-652页

作者： ting-ting lu Xia Tao Hua-Lei Li Ling Gai Hua Huang Feng Li Department of Laboratory Medicine Affiliated Hospital of Nantong UniversityNantong 226001China Department of Pathology Nantong University Medical SchoolNantong 226001China Department of Pharmacy Affiliated Hospital of Nantong UniversityNantong 226001China Department of Urology Affiliated Hospital of Nantong UniversityNantong 226001China Department of Chemotherapy Affiliated Hospital of Nantong UniversityNantong 226001China Department of Pathology Affiliated Hospital of Nantong UniversityNantong 226001China

The onset of prostate cancer(PCa)is often hidden,and recurrence and metastasis are more likely to occur due to chemotherapy ***,we identified downregulated long noncoding RNA(lncRNA)growth arrest-specific 5(GAS5)in PCa that was associated with metastasis and paclitaxel ***5 acted as a tumor suppressor in suppressing the proliferation and metastasis of paclitaxel-resistant PCa ***5 overexpression in vivo inhibited the tumor growth of xenografts and elevated PCa sensitivity to *** of GAS5 and paclitaxel treatment showed great potential in PCa ***,mechanistic analysis revealed a novel regulatory network of GAS5/miR-18a-5p/serine/threonine kinase 4(STK4)that inhibits epithelial-to-mesenchymal transition(EMT)and enhances tumor stem cell-like-mediated sensitivity to paclitaxel in *** findings provide a novel direction for the development of a potential adjunct to cancer chemotherapy that aims to improve the sensitivity of chemotherapy drugs in PCa.

关键词： epithelial-to-mesenchymal transition growth arrest-specific 5 long noncoding RNA paclitaxel prostate cancer

颈动脉支架置入术后发生并发症风险预测模型ABCD的构建与验证

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中华老年心脑血管病杂志 2024年第9期26卷 1035-1038页

作者：卢婷王建红薛朝杨范羽温贤秀杨杰四川省医学科学院·四川省人民医院神经内科成都610072 四川省医学科学院·四川省人民医院护理部成都610072

目的探讨颈动脉支架置入术(carotid artery stenting, CAS)术后1年发生并发症的危险因素,基于危险因素建立并发症的风险预测模型并验证。方法回顾性选取2017年1月至2021年12月于四川省人民医院神经内科行CAS的颈动脉狭窄患者313例。根... 详细信息

目的探讨颈动脉支架置入术(carotid artery stenting, CAS)术后1年发生并发症的危险因素,基于危险因素建立并发症的风险预测模型并验证。方法回顾性选取2017年1月至2021年12月于四川省人民医院神经内科行CAS的颈动脉狭窄患者313例。根据CAS术后复查时间的先后顺序以3:1的比例分为建模组235例和验证组78例,建模组根据有无并发症分为无并发症组182例和并发症组53例。比较建模组与验证组一般资料,采用单因素logistic分析和多因素logistic分析发生并发症的危险因素,采用逻辑评分法构建模型,采用ROC曲线下面积(area under curve, AUC)验证模型。结果多因素logistic分析显示,抗血小板药物未遵医嘱服用、体质量指数异常、吸烟史、高低密度脂蛋白胆固醇是CAS术后1年发生并发症的独立危险因素(OR=65.656,95%CI:12.052~357.683,P=0.000;OR=2.298,95%CI:1.023~5.163,P=0.044;OR=5.965,95%CI:2.527~14.079,P=0.000;OR=6.290,95%CI:1.828~21.645,P=0.004)。建模组AUC为0.827,验证组AUC为0.806。结论抗血小板药物未遵医嘱服用、体质量指数异常、吸烟史、高低密度脂蛋白胆固醇是CAS术后1年发生并发症的独立危险因素。本研究构建的ABCD风险预测模型具有良好的区分度和准确性,可为临床早期识别和预防CAS术后并发症的高危人群提供参考。

关键词：颈动脉狭窄卒中危险因素颈动脉支架置入术风险预测模型

Fine Particulate Matter Exposure Induces Toxicity by Regulating Nuclear Factor-κB/toll-like Receptor 4/myeloid Differentiation Primary Response Signaling Pathways in RAW264.7 Cells

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Biomedical and Environmental Sciences 2023年第5期36卷 458-462页

作者： ZHENG Mei Zhu lu Yao lu ting ting QIN Peng LI Yu Qiu SHI Dong Fang The Central Laboratory Changchun Normal UniversityChangchun 130000JilinChina College of Life Science Changchun Normal UniversityChangchun 130000JilinChina Soybean Research Institute Jilin Academy Agricultural of ScienceChangchun 130033JilinChina

Global air pollution has become a major threat to human health. Daily variations in air pollution have been linked to increased risks of cardiopulmonaryrelated morbidity and mortality. In particular, fine particulate matter(PM) with an aerodynamic diameter ≤ 2.5 μm(PM2.5), which mostly originates from coal combustion, vehicle exhaust, and open sources in Chinese cities, is detrimental to health[1].Epidemiological and experimental investigations have demonstrated that long-term exposure to PM2.5, the most dangerous particulate in the Earth’s atmosphere, is a pivotal risk factor for cardiorespiratory diseases.

关键词： pollution mostly Earth

China＇s Nonfinancial Corporate Debt Dynamics

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China & World Economy 2016年第1期24卷 1-17页

作者： Yongding Yu ting lu Associate Research Fellow Institute of World Economics and Politics Chinese Academy of Social Sciences Beijing China

Since the global financial crisis broke out in 2008, China＇s nonfinancial corporate debt has been rising steadily and rapidly, posing serious threat to China ＂s financial stability. China ＂s rising corporate debt is mainly attributable to three factors： worsening capital efficiency, worsening corporate profitability and high funding costs. Based on a dynamic recursive model developed in the paper, we simulate the trajectories of China＇s corporate debt-to- GDP ratio, and find that if China fails to reverse the current trends in capital efficiency, corporate profitability and financing costs, China ＂s nonfinancial corporate debt-to-GDP ratio will continue to rise without converging to a limit. Against most economists ＇ intuition, given the current trends of changes in parameters, higher economic growth will not help China to escape the corporate debt trap. On the contrary, it will make China ＂s corporate debt problem even worse. To avert a corporate debt crisis, China needs to speed up the structural reform and change the growth paradigm so as to enhance capital efficiency and firms＇ profitability, while reducing firms ＇financing costs.

关键词： debt-to-GDP ratio financial stability nonfinancial corporate debt

Influence of vibration on the grain flow sensor during the harvest and the difference elimination method

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International Journal of Agricultural and Biological Engineering 2021年第5期14卷 149-162页

作者： Pengfei Qian ting lu Cheng Shen Shuren Chen Key Laboratory of Modern Agricultural Equipment and Technology Ministry of EducationJiangsu UniversityZhenjiang 212013JiangsuChina School of Mechanical Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina Nanjing Institute of Agricultural Mechanization Ministry of Agriculture and Rural AffairsNanjing 210014China

The grain yield data collected by the intelligent yield measurement system of the combine harvester is generated into a field plot yield distribution map,which is of great significance for guiding agricultural ***,in the process of drawing the yield map,the combine harvester is affected by vibration during operation and the generated error data in the process of collecting data which will cause the drawing results to be *** study researched two factors that cause errors,then,the influence of vibration interference on the measurement signal was eliminated by filtering,vibration isolation,and designing a double-plates differential grain flow *** methods were taken to eliminate random errors,gross errors and systematic errors,including using the arithmetic average value to replace the true value,the 3σcriterion,and removing the filling time data and the delaying time ***,the grain yield distribution map was obtained through Matlab and *** results showed that the interference frequency above 50 Hz could be eliminated by filtering,but it was difficult to filter the low-frequency signal which was close to the grain impact *** vibration amplitude was reduced to 14.29%by adding a vibration isolation plate,and the SNR was increased from−4.67 dB to 29.21 dB by combining low-pass filtering and damping vibration *** the grain feeding rate was 2 kg/s,the natural vibration amplitude of the sensor after difference was about 0.02 V and evenly distributed around the zero voltage 0.2 *** influence of positive and negative offset on the average value of grain impact signal could be ignored,and the signal-to-noise ratio was increased from 29.21 dB to 62.49 *** results of field experiments showed that the yield map drawn can clearly display the yield value of the harvest area,which is used to guide agricultural production.

关键词： combine harvester grain flow sensor vibration interference double-plates differential elimination method

Factors for wireless operators'collusion and competition

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 61-64页

作者： WEN Dan-hui CHEN Rong-bang lu ting-jie School of Economics and Management Tsinghua UniversityBeijing 100084 China School of Higher Vocational Education Henan Polytechnic UniversityJiaozuo 454000 China School of Economics and Management Science Beijing University of Posts andTelecommunications Beijing 100876 China

This article analyses on why China Mobile and China Unicom have chosen price war rather than tacit collusion these years. On the basis of the analysis on factors that influence tacit collusion, and combined with the facts of wireless communication market, the author suggests that the market asymmetries, cost asymmetries, and product differentiation are the basic factors, which trigger price competition between the Chinese wireless operators. By constructing a game model based on Chum rate, this article discusses how these factors cause a fight between the operators and how vigorous the price competition will be. At last, the author suggests that to keep vigor in this industry, continuous structural adjustment is essential. Besides, the number portability policies may cause tacit collusion.

关键词： chum rate wireless communication collusion,market asymmetries cost asymmetries product differentiation