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Study of the interfacial interactions in the molybdenite floatation system

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Journal of China University of Mining and Technology 2008年第1期18卷 82-87页

作者： wang hui GU Guo-hua FU Jian-gang CHEN Li HAO Ye School of Chemistry and Chemical Engineering Central South University Changsha Hunan 410083 China

Interfacial interactions involving Van der Waals force, hydrophobic attractive force and hydration exclusive force were investigated in this paper. The interfacial interactive free energy of a series of interfaces occurring between minerals, water, collectors and bubble was calculated. The results show that a Van der Waals attractive force and a hydrophobic attractive force exist between each mineral and water interface. The hydrophobic attractive force between molybdenite and water is markedly weaker than the hydrophobic attractive force between gangue and water. The hydrophobic attractive force between collector molecules and water is the main driving force that causes the collectors to become dispersed in the pulp. The strong hydrophobic attractive force between molybdenite and the bubble interface is the basic reason for the natural floatability of molybdenite. The Van der Waals force between molybdenite and the collectors is attractive in water solution, but it is not the cause of the main force between them. The main force that results in the collection effect is a hydrophobic attractive force caused by the Lewis acid-base interaction at the molybdenite surface. A floatation experiment shows that the adsorption intensity of the collector on the molybdenite surface is not the crucial factor for molybdenite floatation. Rather, the dispersing capability of the collector in the water phase and its selectivity for the various minerals in the floatation system are more important.

关键词： molybdenite flotation interfacial interaction contact angle surface free energy

政府会计、财政透明度与经济治理——基于中国省级面板数据的经验研究

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中国软科学 2020年第3期 161-170页

作者：王汇华东北财经大学会计学院辽宁大连116025

文章从理论上构建符合经济治理需求的包含预算、财务和管理会计的政府会计体系,并以我国2007-2014年省级数据实证检验了政府会计信息披露对促进经济增长和抑制经济风险的作用。研究发现,政府会计信息披露质量的提升能够显著促进经济发展... 详细信息

文章从理论上构建符合经济治理需求的包含预算、财务和管理会计的政府会计体系,并以我国2007-2014年省级数据实证检验了政府会计信息披露对促进经济增长和抑制经济风险的作用。研究发现,政府会计信息披露质量的提升能够显著促进经济发展,抑制地区经济风险水平,以及能够显著缓解经济风险对经济增长的削弱作用,当前经济制度形势下通过提高财政透明度来提高经济治理能力是有效途径,地区经济发展水平和居民受教育水平在上述影响中具有显著的正向调节效应。本文在一定程度深化了政府会计与经济治理的理论研究,就如何提升国家治理对政府相关部门提出了完善政府会计体系,提升会计信息质量,促进财政透明度提升,助力"稳增长"与"防风险"的经济治理,促进区域协调发展与提升教育水平等政策建议。

关键词：政府会计经济治理财政透明度

Thermodynamic analysis on tin precipitation behavior in Ti-bearing peritectic steel after magnesium treatment

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Journal of Central South University 2020年第12期27卷 3637-3651页

作者： QU Tian-peng wang De-yong wang hui-hua HOU Dong TIAN Jun Shagang School of Iron and Steel Soochow UniversitySuzhou 215021China

TiN,which is ubiquitous in Ti-bearing steel,has a critical influence on both the mechanical properties and the welding process of steel,and therefore researche on the precipitation behavior of TiN in molten steel bath is of great *** this paper,Ti-bearing peritectic steel was taken as the study object and FactSage was adopted to explore how the precipitation behavior of typical inclusions in steel was affected by the steel ***,microsegregation models were used to analyze the precipitation process of TiN at solidification front,and the calculation results were finally verified by scanning electron microscope(SEM).Research showed that a multitude of dispersed particles of high melting oxide MgAl2O4 or MgO always existed in molten steel after magnesium *** consideration of the segregation and enrichment of solute elements at the solidification front,the Ohnaka microsegregation model was employed to compute the precipitation during *** the event of the solid fraction reaching 0.95 or more,the concentration product of[Ti][N]at the solidification front exceeded the equilibrium concentration product,then TiN began to *** or MgAl2O4 cores were generally found in TiN particles of peritectic steel after the magnesium treatment,which was consistent with the thermodynamic calculation ***,the average size of TiN particles was reduced by approximately 49%.This demonstrated that Mg-rich high melting inclusions were formed after the magnesium treatment,by which the heterogeneous nucleation of TiN was promoted it;therefore,favorable nucleation sites were provided for further refining the high-temperature ferrite phase.

关键词： magnesium treatment peritectic steel TiN heterogeneous nucleation thermodynamic analysis

Effects of Panicle Nitrogen Fertilization on Non-Structural Carbohydrate and Grain Filling in Indica Rice

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Agricultural Sciences in China 2010年第11期9卷 1630-1640页

作者： ZHENG Yong-mei, DING Yan-feng, LIU Zheng-hui and wang Shao-hua Key Laboratory of Crop Growth Regulation, Ministry of Agriculture, Nanjing Agriculture University, Nanjing 210 095, P.R.China [a] Key Laboratory of Crop Growth Regulation Ministry of Agriculture Nanjing Agriculture University Nanjing 210 095 P.R. China

Grain filling, a crucial stage of grain yield formation in rice, is usually affected by the panicle nitrogen （N） fertilization. Field and pot culture experiments were conducted to explore the underlying mechanisms of N effect. Two rice cultivars with high lodging resistance were grown in the field and pot. Four panicle N fertilization treatments were conducted in 2006 and repeated in 2007. The result showed that medium level of panicle N fertilization treatment （NM） enhanced the accumulation and translocation of non-structural carbohydrate （NSC） in the stem and sheath. Compared with non-nitrogen treatment （NO）, NM promoted the translocation of labeled ^13C from stem and sheath to grain. But, low level of panicle N fertilization treatment （NL） and high level of panicle N fertilization treatment （NH） showed the negative effect. The endosperm cell, grain length, and grain width of NM increased more quickly than that of NO from 4 to 10 d after anthesis. During the early period of grain filling, sucrose-phosphate synthase （EC 2.***.1.14, SPS） activity were significantly higher for the NM treatment than those of the NL and NH treatments. Sucrose synthase （EC 2.***.1.13, SuSase） activity in the grains was substantially enhanced by NM, with the duration of higher activity being longer than those of the other treatments. At maturing stage, NM significantly increased the filled grain number, the seed-setting rate, and the grain weight compared with NL and NH. The results suggest that NM have a positive effect on the activities of enzymes of physiological importance, thereby increasing the grain size and promoting grain filling.

关键词： rice panicle nitrogen fertilization grain filling non-structural carbohydrate sink capacity sucrose-phosphatesynthase sucrose synthase

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两种宽缝超宽带天线的脉冲波形保真度比较

南京邮电大学学报（自然科学版） 2008年第6期28卷 56-60页

作者：王会华程崇虎南京邮电大学通信与信息工程学院江苏南京210003

设计了两种小型宽缝结构超宽带天线,一种采用接地CPW馈电方式,另一种采用带状线馈电方式。结果表明这两种天线都有较宽的阻抗带宽。分析了两种天线的特性参数,并比较两种天线的增益和辐射特性,给出两种天线在远区场的脉冲波形比较,并得... 详细信息

设计了两种小型宽缝结构超宽带天线,一种采用接地CPW馈电方式,另一种采用带状线馈电方式。结果表明这两种天线都有较宽的阻抗带宽。分析了两种天线的特性参数,并比较两种天线的增益和辐射特性,给出两种天线在远区场的脉冲波形比较,并得出不同天线结构对脉冲波形的保真度的影响,这对实际超宽带脉冲天线的设计与应用意义重大。

关键词：接地共面波导带状线超宽带脉冲天线脉冲保真度

Prehospital road traffic injuries among the elderly in Beijing, China： data from the Beijing Emergency Medical Center, 2004-2010

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Chinese Medical Journal 2013年第15期126卷 2859-2865页

作者： AN Shuai ZHANG Jin-jun ZHANG Pei-xun YIN Xiao-feng KOU Yu-hui wang Yan-hua wang Zhen-wei JIANG Bao-guo wang Tian-bing Peking Univ Peoples Hosp Dept Orthopaed & Traumatol Beijing 100044 Peoples R China Peking Univ Traff Med Ctr Beijing 100191 Peoples R China Beijing Emergency Med Ctr Beijing 100031 Peoples R China

Background Road traffic injuries （RTIs） are a worldwide issue associated with increasing development and motorization. However, statistical studies do not include any analyses of Beijing＇s geriatric population. Using data from the Beijing Emergency Medical Center, we present the main characteristics of traffic injuries involving the elderly in Beijing. We also provide objective information for those concerned with the safety of traffic systems and the prevention of traffic injuries. Methods In a longitudinal, retrospective study, data were collected on 1706 victims aged 65 years and older who sustained traffic injuries in Beijing between 2004 and 2010. Personal information, time of injury event, emergency care response time, road user type, striking vehicle type, injury site, and severity of injury were analyzed using ;~2 tests and Logistic regression analysis. Results The annual rate of traffic injuries was 21.80 per 100 000 elderly people in Beijing, and the morbidity rate decreased from 2004 to 2010 （P 〈0.001）. The mean age was （72.92＋5.67） years, and 911 （53.40%） of the victims were male. The majority of victims sustained head and lower limb injuries and were classified as being of medium severity. Traffic collisions occurred most frequently in the daytime excluding rush hours; these collisions included being hit by a car （85.64%） and pedestrian victim injuries （79.19%）. Our statistical analysis found three factors for injury severity： abdominal injuries （P 〈0.001）, number of injury sites （P=0.027）, and head injuries （P=0.034）. The decline in traffic injuries is due to a decrease in victims aged 65-74 years and pedestrians; the sevedty of RTIs also decreased. Conclusions This study highlights the declining trend in traffic injuries among older adults in Beijing. However, traffic injuries remain a serious public health problem for the elderly and effective measures are required to reduce their incidence.

关键词： road traffic injury older adults emergency medical services

联合免疫婴儿的娩出方式对乙型肝炎病毒母婴传播影响的Meta分析

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中华预防医学杂志 2010年第3期44卷 221-223页

作者：王慧华王正平浙江大学医学院附属妇产科医院杭州310006

目的综合评价乙型肝炎（乙肝）疫苗及乙肝免疫球蛋白联合免疫婴儿的娩出方式对乙肝病毒（HBV）母婴垂直传播的影响。方法系统检索相关文献，共696篇，按纳入及排除标准从中选择符合标准的7篇文献，进行Meta分析，评估乙肝主动和被动联... 详细信息

目的综合评价乙型肝炎（乙肝）疫苗及乙肝免疫球蛋白联合免疫婴儿的娩出方式对乙肝病毒（HBV）母婴垂直传播的影响。方法系统检索相关文献，共696篇，按纳入及排除标准从中选择符合标准的7篇文献，进行Meta分析，评估乙肝主动和被动联合免疫婴儿的娩出方式对婴儿HBV感染率的影响。结果共检索到符合标准的文献7篇，共1435名研究对象。自然分娩组831名婴儿，61例感染HBV，阳性率为7．34％；剖宫产组604名婴儿，29例感染HBV，阳性率为4．80％。婴儿HBV感染率两组间差异无统计学意义（OR合计=0．70，95％CI：0．45～1．11，Z=1．52，P=0．13）。

关键词：肝炎病毒乙型分娩疾病传播垂直 Meta分析[文献类型]

公立医院品牌传播的感性诉求策略——基于ELM的研究

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中国卫生事业管理 2015年第1期32卷 29-30,47页

作者：王慧华南京中医药大学江苏南京210023

公立医院品牌传播作为公立医院品牌建设的有效途径之一,不如公立医院宣传为人熟知。精细加工可能性模型指出了信息说服活动中边缘路径存在的必然性,并分析了感性诉求要点,为公立医院品牌传播提供了理论依据。公立医院品牌传播的感性诉... 详细信息

公立医院品牌传播作为公立医院品牌建设的有效途径之一,不如公立医院宣传为人熟知。精细加工可能性模型指出了信息说服活动中边缘路径存在的必然性,并分析了感性诉求要点,为公立医院品牌传播提供了理论依据。公立医院品牌传播的感性诉求策略以公众情感为出发点,选择容易与公众产生情感共鸣的信息内容,并以自尊、权威、同情、关联和普通人等感性诉求表现形式,从而通过边缘路径使公众对公立医院品牌态度发生改变。

关键词：公立医院品牌传播感性诉求精细加工可能性模型

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合肥“新地中心”超长地下室结构无缝设计

工程抗震与加固改造 2012年第5期34卷 111-115页

作者：王华辉中国建筑科学研究院建筑设计院北京100013

通过合肥新地中心超长地下室结构的无缝设计,介绍了补偿收缩混凝土无缝设计原理和裂缝控制原则;综合考虑混凝土水化热、混凝土收缩和徐变、环境温差影响及膨胀剂的补偿收缩作用影响,计算分析了膨胀加强带的设置间距和限制膨胀率的取值... 详细信息

通过合肥新地中心超长地下室结构的无缝设计,介绍了补偿收缩混凝土无缝设计原理和裂缝控制原则;综合考虑混凝土水化热、混凝土收缩和徐变、环境温差影响及膨胀剂的补偿收缩作用影响,计算分析了膨胀加强带的设置间距和限制膨胀率的取值。实践表明,合理设置膨胀加强带,采用补偿收缩混凝土,采取有效的结构和施工措施,本工程超长地下室可不设伸缩缝,实现无缝设计。本文给出的思路和方法,可为其他超长地下室结构的无缝设计提供参考。

关键词：超长地下室无缝设计膨胀加强带补偿收缩混凝土