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Interannual evolution of the chemical composition,sources and processes of PM_(2.5)in Chengdu,China:Insights from observations in four winters

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Journal of Environmental Sciences 2024年第4期138卷 32-45页

作者： Junke Zhang Jiaqi Li Yunfei Su Chunying Chen Luyao Chen Xiaojuan Huang fangzheng wang Yawen Huang Gehui wang Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Department of Environmental Science&Engineering Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3)Fudan UniversityShanghai 200438China Key Lab of Geographic Information Science of the Ministry of Education School of Geographic SciencesEast China Normal UniversityShanghai 200241China

The air quality in China has improved significantly in the last decade and,correspondingly,the characteristics of PM_(2.5)have also *** studied the interannual variation of PM_(2.5)in Chengdu,one of the most heavily polluted megacities in southwest China,during the most polluted season(winter).Our results show that the mass concentrations of PM_(2.5)decreased significantly year-by-year,from 195.8±91.0μg/m~3in winter 2016 to 96.1±39.3μg/m^(3)in winter *** mass concentrations of organic matter(OM),SO_()4^(2-),NH_(4)^(+)and NO_(3)^(-)decreased by 49.6%,57.1%,49.7% and 28.7%,*** differential reduction in the concentrations of chemical components increased the contributions from secondary organic carbon and NO_(3)^(-)and there was a larger contribution from mobile *** contribution of OM and NO_(3)^(-)not only increased with increasing levels of pollution,but also increased year-by-year at the same level of *** sources of PM_(2.5)were identified:combustion sources,vehicular emissions,dust and secondary *** aerosols made the highest contribution and increased year-by-year,from 40.6%in winter 2016 to 46.3% in winter *** contrast,the contribution from combustion sources decreased from 14.4% to 8.7%.Our results show the effectiveness of earlier pollution reduction policies and emphasizes that priority should be given to key pollutants(e.g.,OM and NO_(3)^(-))and sources(secondary aerosols and vehicular emissions)in future policies for the reduction of pollution in Chengdu during the winter months.

关键词： PM_(2.5) Chemical composition Sources Interannual evolution Winter Chengdu

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双馈风机对电网频率扰动的动态响应建模与分析

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电力系统自动化 2024年第9期48卷 75-85页

作者：李鲁阳王方政陈磊王罗闵勇刘喜泉清华大学电机工程与应用电子技术系北京市100084 中国长江三峡集团有限公司科学技术研究院北京市100038

含高比例新能源和高比例电力电子设备的电力系统频率调节能力下降,频率安全问题突出。新能源发电设备利用电力电子接口并网,一般采用最大功率点跟踪控制,被认为不响应系统频率变化。但是,双馈风机通过定子回路与电网直接耦合,会在机电... 详细信息

含高比例新能源和高比例电力电子设备的电力系统频率调节能力下降,频率安全问题突出。新能源发电设备利用电力电子接口并网,一般采用最大功率点跟踪控制,被认为不响应系统频率变化。但是,双馈风机通过定子回路与电网直接耦合,会在机电耦合与转子回路解耦控制的共同作用下对频率扰动产生复杂的响应。已有研究注意到该特性,但目前还缺乏准确描述双馈风机频率响应过程的模型和对特性机理的深入分析。为此,提出一种不依赖并网点电压信息、可直接集成于电力系统频率响应模型的双馈风机降阶频率响应模型。利用该模型揭示了双馈风机的频率响应机制为锁相环和外环的级联耦合效应,并证明其频率响应不属于惯量响应的范畴。最后,分析了双馈风机对电力系统频率动态的影响。

关键词：双馈风机频率响应新能源频率安全惯量响应

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法律视角下的第三方物流监管难题及治理路径

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物流科技 2024年第8期47卷 14-16,23页

作者：王方正扬州大学江苏扬州225009

随着我国经济的突飞猛进,现代物流行业迎来前所未有的发展机遇。然而,我国传统的第一方物流和第二方物流行业,其组织和管理模式已经无法满足当今社会对物流的多元化需求。于是,第三方物流行业应运而生,相比传统物流,它更加专业化,针对... 详细信息

随着我国经济的突飞猛进,现代物流行业迎来前所未有的发展机遇。然而,我国传统的第一方物流和第二方物流行业,其组织和管理模式已经无法满足当今社会对物流的多元化需求。于是,第三方物流行业应运而生,相比传统物流,它更加专业化,针对性更强,运作成本也不高,效率也得到提高,同时也符合现代物流业的发展趋势。但是第三方物流也存在很多问题,其主要原因是缺乏法律方面的监管,而且对这一方面的研究也是少之又少,所以针对第三方物流建立监管法律制度已经迫在眉睫。文章首先介绍我国第三方物流的概念和特点,之后对第三方物流监管方面存在的问题进行分析,最后提出相对合理的治理路径。

关键词：第三方物流监管体系物流法

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Heating of heavy oil by circulating hot water in closed double casing in ultra-deep wells

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Petroleum Science 2012年第4期9卷 506-510页

作者： Lin Riyi wang fangzheng wang Xinwei College of Pipeline and Civil Engineering China University of Petroleum(East)QingdaoShandong 266580China

In heavy oil production,the loss of energy to ambient surroundings decreases the temperature of the heavy oil flowing upwards in a vertical wellbore,which increases the oil viscosity and the oil may not flow normally in the ***,it is necessary to lower the heavy oil viscosity by heating methods to allow it to be lifted *** of heavy oil in an oil well is achieved by circulating hot water in annuli in the well（tubing-casing annulus,casing-casing annulus）.In this paper,based on heat transfer principles and fluid flow theory,a model is developed for produced fluids and hot water flowing in a vertical *** temperature and pressure of produced fluids and hot water in the wellbore are calculated and the effect of hot water on heavy oil temperature is *** results show that the hot water circulating in the annuli may effectively heat the heavy oil in the tubing,so as to significantly reduce both oil viscosity and resistance to oil flow.

关键词： Heavy oil double casing hot water injection viscosity reduction

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Long-term follow-up of right ventricular outflow tract septal pacing

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老年心脏病学杂志：英文版 2009年第2期6卷 71-74页

作者： Xiaoqing Ren Shu Zhang Jielin Pu fangzheng wang Center of Arrhythmia Diagnosis and Treatment Fuwai Hospital and Cardiovascular Institute Peking Union Medical College and Chinese Academy of Medical Sciences Beijing 100037 China

客观恰好室的流出道中隔广泛地变得使用我们一个电极放置地点。然而，有关为与这种技术重新定位的铅的铅表演和复杂并发症的数据是欠缺的。这研究的目的是观察长期的铅表演和恰好室的流出道的复杂并发症氏族的踱步并且为选择一个最佳的... 详细信息

客观恰好室的流出道中隔广泛地变得使用我们一个电极放置地点。然而，有关为与这种技术重新定位的铅的铅表演和复杂并发症的数据是欠缺的。这研究的目的是观察长期的铅表演和恰好室的流出道的复杂并发症氏族的踱步并且为选择一个最佳的电极培植地点提供证据。方法有氏族的活跃电极培植的 36 个病人并且 39 在这研究与顶端的被动电极培植被注册。为在培植和后续的二个组的踱步的阀值，察觉到的 R 波浪，铅阻抗，踱步的 QRS 宽度和步相关的复杂并发症被比较。在那里的结果更高与顶端的组相比在氏族的组在培植正在在阀值和更短的踱步 QRS 宽度上踱步。在之间没有差别氏族并且在在后续期间在阀值， R 波浪敏感，铅阻抗和步相关的复杂并发症上踱步的顶端的组。因为它与传统的顶端的地点相比有长期的稳定的铅表演和没有严肃的复杂并发症，结论恰好室的流出道中隔能为培植地点被用作第一种选择。

关键词：右心室起搏离子植入选择电极随访 QRS波并发症网站

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Cardiac atrioventricular conduction improved by autologous transplantation of mesenchymal stem cells in canine atrioventricular block models

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Journal of Geriatric Cardiology 2007年第4期4卷 238-243页

作者： Xiaoqing Ren Jielin Pu Shu Zhang Liang Meng fangzheng wang Cardiac Arrhythmia Center Cardiovascular Institute and Fuwai Hospital CAMS and PUMC Beijing 100037 China Cardiac Arrhythmia Center Cardiovascular Institute and Fuwai Hospital CAMS and PUMC Beijing 100037 China Cardiac Arrhythmia Center Cardiovascular Institute and Fuwai Hospital CAMS and PUMC Beijing 100037 China Cardiac Arrhythmia Center Cardiovascular Institute and Fuwai Hospital CAMS and PUMC Beijing 100037 China Cardiac Arrhythmia Center Cardiovascular Institute and Fuwai Hospital CAMS and PUMC Beijing 100037 China

Objective Atrioventricular block (AVB) is a common and serious arrhythmia. At present, there is no perfect method of treatment for this kind of arrhythmia. The purpose of this study was to regenerate cardiac atrioventricular conduction by autologous transplantation of bone marrow mesenchymal stem cells (MSCs), and explore new methods for therapy of atrioventricular block. Methods Eleven Mongrel canines were randomized to MSCs transplantation (n=6) or control (n=5) group. The models of permanent and complete AVB in 11 canines were established by ablating His bundle with radiofrequency technique. At 4 weeks after AVB, bone marrow was aspirated from the iliac crest. MSCs were isolated and culture-expanded by means of gradient centrifugal and adherence to growth technique, and differentiated by 5-azacytidine in vitro. Differentiated MSCs (1ml, 1.5×107cells) labeled with BrdU were autotransplanted into His bundle area of canines by direct injection in the experimental group, and 1ml DMEM in the control group. At 1-12 weeks after operation, the effects of autologous MSCs transplantation on AVB models were evaluated by electrocardiogram, pathologic and immunohistochemical staining technique. Results Compared with the control group, there was a distinct improvement in atrioventricular conduction function in the experimental group. MSCs transplanted in His bundle were differentiated into analogous conduction system cells and endothelial cells in vivo, and established gap junction with host cardiomyocytes. Conclusions The committed-induced MSCs transplanted into His bundle area could differentiate into analogous conduction system cells and improve His conduction function in canine AVB models. (J Geriatr Cardiol 2007;4:238-243.)

关键词： mesenchymal stem cells His bundle cell transplantation differentiation 5-azacytidine

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Foreword

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Journal of China University of Geosciences 2004年第2期15卷 133-134页

作者： Lü guxian,wang fangzheng,Liu Ruixun

Since the discovery of a lot of eclogites with coesite and diamond inclusions related to the continent-continent collision-orogeny environment, the ultrahigh-pressure metamorphism (UHPM) in the Dabie-Sulu has aroused great interest in geologists. Experimental studies have proved that such minerals as diamond, coesite and omphacite etc. formed at pressures 2-5 GPa (and corresponding temperatures). However, it does not mean that by the formation pressure we can directly determine that the metamorphic rocks are the products of a deep-seated subducting plate downward to depths of 100-200 km and then returning to the surface. The calculation method of P/SW (depth=pressure/specific gravity), i.e. the formula of pressure=depth×specific gravity, needs to be thought about again.

关键词： PP Foreword

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Epithermal Gold Mineralization in Chinese Tianshan Province

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Journal of Earth Science 2000年第4期19卷 38-43页

作者： Xiao Long wang fangzheng Department of Science and Technology, China University of Geosciences, Wuhan 430074

Tianshan is a part of the complex system of orogenic belts of Phanerozoic in Central Asia. In the northwestern Chinese Tianshan, Borohoro range, the major metallogenic belt in this area is situated between the Yili block and Keguqinshan-Sairim uplift. The intra-arc basins resulting from southward subduction of the Junggar plate and accompanying volcanism are the essential factors for the formation of the hydrothermal system that caused gold mineralization. The adularia-sericite-style epithermal Arxi gold deposit formed in an extensional tectonic setting. In the eastern Tianshan, post-orogenic magmatism resulted in a hydrothermal system that produced the epithermal Xitan gold deposit. Both gold deposits are related to local extensional setting, although differences exist in their timing and location.

关键词： gold deposit mineralization Tianshan China.

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风电机组变桨减载一次调频模型及聚合方法

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电网技术 2023年第4期47卷 1360-1368页

作者：奥博宇王方政陈磊王罗闵勇刘喜泉郭剑波清华大学电机工程与应用电子技术系北京市海淀区100084 中国长江三峡集团有限公司科学技术研究院北京市西城区100038 中国电力科学研究院有限公司北京市海淀区100192

风电参与频率调节已经成为明确的趋势,因此在电力系统频率动态仿真中需要加入风电场的一次调频模型。风电机组通过变桨减载预留备用参与调频是风电调频的一种典型方式,针对该方式建立了风电机组的一次调频模型并提出了风电场调频模型的... 详细信息

风电参与频率调节已经成为明确的趋势,因此在电力系统频率动态仿真中需要加入风电场的一次调频模型。风电机组通过变桨减载预留备用参与调频是风电调频的一种典型方式,针对该方式建立了风电机组的一次调频模型并提出了风电场调频模型的聚合建模方法。首先建立单风机变桨减载一次调频模型,保留风能捕获、转子动态、有功控制和桨距角控制等关键环节,忽略快速的变流器控制过程。然后提出了采用同型号风机的风电场调频模型聚合方法,考虑到风机运行工况和调频能力的差异,以保证聚合前后功率动态过程一致为目标,推导了调频模型参数的聚合等值方法,将多台风机聚合为一台等值机,使得等值机在调频过程中的输出功率尽可能等于各单机输出功率之和。仿真结果验证了所提方法的有效性。

关键词：聚合模型风电机组一次调频频率响应模型

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Determination of the optimal atrioventricular and interventricular delays in cardiac resynchronization therapy

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Journal of Geriatric Cardiology 2005年第4期2卷 207-210页

作者： Hongxia NIU Wei HUA Shu ZHANG fangzheng wang Keping CHEN Xin CHEN Division of Clinical Electrophysiology Fu Wai Hospital and Cardiovascular Institute CAMS and PUMC Beijing 100037 China Division of Clinical Electrophysiology Fu Wai Hospital and Cardiovascular Institute CAMS and PUMC Beijing 100037 China Division of Clinical Electrophysiology Fu Wai Hospital and Cardiovascular Institute CAMS and PUMC Beijing 100037 China Division of Clinical Electrophysiology Fu Wai Hospital and Cardiovascular Institute CAMS and PUMC Beijing 100037 China Division of Clinical Electrophysiology Fu Wai Hospital and Cardiovascular Institute CAMS and PUMC Beijing 100037 China Division of Clinical Electrophysiology Fu Wai Hospital and Cardiovascular Institute CAMS and PUMC Beijing 100037 China

In order to provide the maximum benefit of cardiac resynchronization therapy (CRT), we tried to use an echocardiography method to optimize the atrioventricular and interventricular delay. Methods The study included 6 patients who underwent implantation of biventricular pacemakers for drug-resistant heart failure. Two-dimensional echocardiography and tissue Doppler imaging were carried out before and after the pacemaker implantation. The optimal AV delay was defined as the AV delay resulting in maximum timevelocity integral (TVI) of transmitral filling flow, the longest left ventricular filling time (LVFT) and the minimum mitral regurgitation(MR). The optimal VV delay was defined as the VV delay producing the maximum LV synchrony and the largest aortic TVI. Results CRT was successfully performed in all patients. After pacemaker implantation, an acute improvement in left ventricular ejection fraction (LVEF) was observed from 26.5% to 35%. Meanwhile, the QRS duration decreased from 170ms to 150ms. The optimal AV delay was programmed at 130, 120, 120, 120, 150 and 110ms respectively with heart rate corrected, LVFT significantly lengthened and TVI of MR decreased (non-optimal vs optimal AV delay: LVFT: 469ms vs 523ms; TVI of MR: 16.43cm vs 13.06cm, P＜0.05). The optimal VV delay was programmed at 4, 4, 4, 8, 12 and 8ms with LV preactivation respectively. Programming the optimal VV delay increased the aortic TVI from 17.33cm up to 21.42cm (P＜0.05). In the septal and lateral wall, peak systolic velocities improved from2.70cm/s to 3.02cm/s (P＞0.05) and froml.31cm/s to 2.50cm/s (P＜0.05) respectively. The septal-to-lateral delay in peak velocity improved from 56.4ms to 13.3ms after CRT (P＜0.01). Conclusions Optimization of AV and VV delays may further enhance the efficacy of CRT. However, there was interindividual variability of optimal values, warranting individual patient examination.

关键词： cardiac resynchronization therapy optimal atrioventricular delay optimal interventricular delay tissue Doppler imaging

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