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In, Sn, Pb and Zn Contents and Their Relationships in Ore-forming Fluids from Some In-rich and In-poor Deposits in China 被引量:16
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作者 ZHANG Qian ZHU Xiaoqing +1 位作者 HE Yuliang ZHU Zhaohui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第3期450-462,共13页
All the indium-rich deposits with indium contents in ores more than 100×10^-6 seems to be of cassiterite-sulfide deposits or Sn-bearing Pb-Zn deposits, e.g., in the Dachang Sn deposit in Guangxi, the Dulong Sn-Zn... All the indium-rich deposits with indium contents in ores more than 100×10^-6 seems to be of cassiterite-sulfide deposits or Sn-bearing Pb-Zn deposits, e.g., in the Dachang Sn deposit in Guangxi, the Dulong Sn-Zn deposit in Yunnan, and the Meng'entaolegai Ag-Pb-Zn deposit in Inner Mongolia, the indium contents in ores range from 98×10^-6 to 236×10^-6 and show a good positive correlation with contents of zinc and tin, and their correlation coefficients are 0.8781 and 0.7430, respectively. The indium contents from such Sn-poor deposits as the Fozichong Pb-Zn deposit in Guangxi and the Huanren Pb-Zn deposit in Liaoning are generally lower than 10×10^-6, i.e., whether tin is present or not in a deposit implies the enrichment extent of indium in ores. Whether the In enrichment itself in the ore -forming fluids or the ore-forming conditions has actually caused the enrichment/depletion of indium in the deposits? After studying the fluid inclusions in quartz crystallized at the main stage of mineralization of several In-rich and In-poor deposits in China, this paper analyzed the contents and studied the variation trend of In, Sn, Pb and Zn in the ore-forming fluids. The results show that the contents of lead and zinc in the ore-forming fluids of In-rich and -poor deposits are at the same level, and the lead contents range from 22×10^-6 to 81×10^-6 and zinc from 164×10^-6 to 309×10^-6, while the contents of indium and tin in the ore-forming fluids of In-rich deposits are far higher than those of Inpoor deposits, with a difference of 1-2 orders of magnitude. Indium and tin contents in ore-forming fluid of In-rich deposits are 1.9×10^-6-4.1×10^-6 and 7×10^-6-55×10^-6, and there is a very good positive correlation between the two elements, with a correlation coefficient of 0.9552. Indium and tin contents in ore-forming fluid of In-poor deposits are 0.03×10^-6-0.09×10^-6 and 0.4×10^-6-2.0×10^-6, respectively, and there is no apparent correlation between them. This indicates, on one hand, that In-rich oreforming fluids are the material basis for the formation of In-rich deposits, and, on the other hand, tin probably played a very important role in the transport and enrichment of indium. 展开更多
关键词 In-rich deposit In-poor deposit ore-forming fluid fluid inclusion ore-forming elements
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Poor rich demarcation of Matthew effect on scale-free systems and its application
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作者 闫栋 董明 +1 位作者 Abdelaziz Bourasc 于随然 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期27-32,共6页
In a scale-free network, only a minority of nodes are connected very often, while the majority of nodes are connected rarely. However, what is the ratio of minority nodes to majority nodes resulting from the Matthew e... In a scale-free network, only a minority of nodes are connected very often, while the majority of nodes are connected rarely. However, what is the ratio of minority nodes to majority nodes resulting from the Matthew effect? In this paper, based on a simple preferential random model, the poor-rich demarcation points are found to vary in a limited range, and form a poor-rich demarcation interval that approximates to k/m E [3,4]. As a result, the (cumulative) degree distribution of a scale-free network can be divided into three intervals: the poor interval, the demarcation interval and the rich interval. The inequality of the degree distribution in each interval is measured. Finally, the Matthew effect is applied to the ABC analysis of project management. 展开更多
关键词 Matthew effect scale-free networks poor-rich demarcation project management
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Narrowing Gap Between Rich and Poor
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作者 STAFF REPORTER YUN XIANG 《The Journal of Human Rights》 2005年第2期14-16,共3页
Inequality in distribution has become an issue of public concern in China. Incomes of the Chinese people have grown year after year ever since the reform and opening era began in the late 1970s. Meanwhile, the income ... Inequality in distribution has become an issue of public concern in China. Incomes of the Chinese people have grown year after year ever since the reform and opening era began in the late 1970s. Meanwhile, the income gap between urban and rural residents has widened constantly, from 1.8:1 in the mid-1980s to 3.2:1 in 2003. In a report entitled Analysis and Forecast of China's Social Conditions 2004-2005, experts with the Chinese Academy of Social Sciences listed the widening income gaps as the second most serious of the six problems China is facing. The report notes that such gaps have kept widening not only between individual workers in the same profession but also between workers in different industries and regions. In view of this, the national economic work conference held in early January called for effort to improve the order of income distribution and readjust the distribution of national wealth in an appropriate manner. How to view the problem of inequality in distribution as we see now? How the divide of the rich and the poor affects the improvement of human rights? What should be done to narrow the gap between the rich and the poor? We have dis- cussed these questions with two leading social scientists in China, Sun Guohua, pro- fessor of law at the Renmin University of China and Prof. Hu Angang of Qinghua University, a noted expert in study of the conditions in China. 展开更多
关键词 Narrowing Gap between rich and poor rich BANK HIGH World
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Optimizing band structure of CoP nanoparticles via rich-defect carbon shell toward bifunctional electrocatalysts for overall water splitting 被引量:4
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作者 Juncheng Wu Zhe‐Fan Wang +7 位作者 Taotao Guan Guoli Zhang Juan Zhang Jie Han Shengqin Guan Ning Wang Jianlong Wang Kaixi Li 《Carbon Energy》 SCIE CSCD 2023年第3期112-125,共14页
Transition-metal phosphides(TMPs)with high catalytic activity are widely used in the design of electrodes for water splitting.However,a major challenge is how to achieve the trade-off between activity and stability of... Transition-metal phosphides(TMPs)with high catalytic activity are widely used in the design of electrodes for water splitting.However,a major challenge is how to achieve the trade-off between activity and stability of TMPs.Herein,a novel method for synthesizing CoP nanoparticles encapsu-lated in a rich-defect carbon shell(CoP/DCS)is developed through the self-assembly of modified polycyclic aromatic molecules.The graft and removal of high-activity C-N bonds of aromatic molecules render the controllable design of crystallite defects of carbon shell.The density functional theory calculation indicates that the carbon defects with unpaired electrons could effectively tailor the band structure of CoP.Benefiting from the improved activity and corrosion resistance,the CoP/DCS delivers outstanding difunctional hydrogen evolution reaction(88 mV)and oxygen evolution reaction(251 mV)performances at 10 mA cm^(−2)current density.Furthermore,the coupled water electrolyzer with CoP/DCS as both the cathode and anode presents ultralow cell voltages of 1.49 V to achieve 10 mA cm^(−2)with long-time stability.This strategy to improve TMPs electrocatalyst with rich-DCS and heterogeneous structure will inspire the design of other transition metal compound electrocatalysts for water splitting. 展开更多
关键词 band structure bifunctional electrocatalysts CoP nanoparticles overall water splitting rich‐defect carbon
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The Rich Help the Poor
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《China Today》 1997年第2期12-14,共3页
关键词 the rich Help the poor
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The Rich Help the Poor
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作者 KUANG YI 《China Today》 1996年第10期41-43,共3页
TheRichHelpthePoorMoreandmorewealthyregionsandbusinesspeopleareparticipatinginthecampaignagainstpoverty,andh... TheRichHelpthePoorMoreandmorewealthyregionsandbusinesspeopleareparticipatinginthecampaignagainstpoverty,andhavemadeconsiderab... 展开更多
关键词 the rich Help the poor
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On the Pain Points and Governance of the Constructionof the Socialist Market Economy in Contemporary China
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作者 夏德建 《石家庄经济学院学报》 2016年第3期6-10,共5页
经过3 0 多年的改革开放,中国的社会主义市场经济建设取得了丰硕成果,成为了中国特色社会主义制度的重要支柱,奠定了建设全面小康社会的坚实基础.但是,随着我国经济步入深化发展与转型调整阶段,市场的优化配置功能在社会管理、公共产品... 经过3 0 多年的改革开放,中国的社会主义市场经济建设取得了丰硕成果,成为了中国特色社会主义制度的重要支柱,奠定了建设全面小康社会的坚实基础.但是,随着我国经济步入深化发展与转型调整阶段,市场的优化配置功能在社会管理、公共产品供应等民生问题上出现了越位、缺位等异化现象,引发了官民对立、干群关系紧张、贫富两极分化、社会保障缺失等不和谐问题,严重掣肘了中国社会主义市场经济的健康与持续发展D 为治理上述痛点,论文提出了党要坚持执政为民的治国理念、完善社会考评制度、合理分配社会财富、健全社会保障体系等治理上的一些简单思路,以起抛砖引玉之效. 展开更多
关键词 社会主义市场经济 改革开放 资源分配 贫富差距 社会保障
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Neutron-Capture Elements in the Double-Enhanced Star HE 1305-0007: a New s- and r-Process Paradigm
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作者 崔文元 崔冬暖 +1 位作者 杜云霜 张波 《Chinese Physics Letters》 SCIE CAS CSCD 2007年第5期1417-1420,共4页
The star HE 1305-0007 is a metal-poor double-enhanced star with metallicity [Fe/H] = -2.0, which is just at the upper limit of the metallicity for the observed double-enhanced stars. Using a parametric model, we find ... The star HE 1305-0007 is a metal-poor double-enhanced star with metallicity [Fe/H] = -2.0, which is just at the upper limit of the metallicity for the observed double-enhanced stars. Using a parametric model, we find that almost all s-elements were made in a single neutron exposure. This star should be a member of a post-commonenvelope binary. After the s-process material has experienced only one neutron exposure in the nucleosynthesis region and is dredged-up to its envelope, the AGB evolution is terminated by the onset of common-envelope evolution. Based on the high radial-velocity of HE 1305-0007, we speculate that the star could be a runaway star from a binary system, in which the AIC event has occurred and produced the r-process elements. 展开更多
关键词 ASYMPTOTIC GIANT BRANCH METAL-poor STARS rich STARS GALACTIC HALO CARBONSTARS DREDGE-UP EVOLUTION NUCLEOSYNtheSIS MODEL ORIGIN
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基尼系数测度贫富差距的一种改进方法
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作者 彭妮娅 《统计与决策》 北大核心 2024年第4期12-16,共5页
基尼系数是测度贫富差距的重要指标,但是洛伦兹曲线的构造使得基尼系数存在结构性局限,即代表着不同的贫富差距情况的两条洛伦兹曲线可能对应着同一个基尼系数,仅凭基尼系数无法反映贫富差距的结构特征。文章提出将洛伦兹曲线上切线斜率... 基尼系数是测度贫富差距的重要指标,但是洛伦兹曲线的构造使得基尼系数存在结构性局限,即代表着不同的贫富差距情况的两条洛伦兹曲线可能对应着同一个基尼系数,仅凭基尼系数无法反映贫富差距的结构特征。文章提出将洛伦兹曲线上切线斜率为1的点叫做平均增长点,每条洛伦兹曲线有且仅有一个平均增长点,洛伦兹曲线切线斜率具有单调性,可以通过引入平均增长点,与基尼系数共同测度贫富差距,突破单纯依靠基尼系数测度贫富差距的结构性局限。 展开更多
关键词 基尼系数 贫富差距 结构性局限 平均增长点
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主佃借贷与贫富相资——对宋代契约租佃制下富民借贷的探讨
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作者 黎志刚 《思想战线》 北大核心 2024年第1期75-82,共8页
宋代是我国古代民间借贷关系空前发展的重要时期。随着富民阶层的崛起和契约租佃主导地位的确立,民间借贷关系与契约租佃关系的结合表现得越来越紧密,有效地实现了生产要素的优化配置,逐渐成为当时重要的制度选择和制度安排。而宋政府... 宋代是我国古代民间借贷关系空前发展的重要时期。随着富民阶层的崛起和契约租佃主导地位的确立,民间借贷关系与契约租佃关系的结合表现得越来越紧密,有效地实现了生产要素的优化配置,逐渐成为当时重要的制度选择和制度安排。而宋政府也逐渐认识并重视这一点,利用主佃借贷来实现贫富相资,促进了乡村经济的稳定和发展。 展开更多
关键词 契约租佃关系 富民阶层 主佃借贷 贫富相资
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Co_(3)O_(4)@碳纤维诱导贫/富电子中心活化PMS高效降解2,4-二氯酚
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作者 张禹洵 卫月星 +4 位作者 焦路畅 秦育红 申浩楠 贺冲 崔丽萍 《太原理工大学学报》 CAS 北大核心 2024年第3期538-549,共12页
【目的】工业快速发展导致水体中氯酚类污染物含量上升,对生态系统和人类生存发展造成影响,高效降解工业废水中难降解污染物2,4-二氯酚(2,4-DCP)成为。【方法】通过一步浸渍法制备了具有贫/富电子活性中心的Co_(3)O_(4)包覆碳纤维催化剂... 【目的】工业快速发展导致水体中氯酚类污染物含量上升,对生态系统和人类生存发展造成影响,高效降解工业废水中难降解污染物2,4-二氯酚(2,4-DCP)成为。【方法】通过一步浸渍法制备了具有贫/富电子活性中心的Co_(3)O_(4)包覆碳纤维催化剂(Co_(3)O_(4)@CF),并应用于活化过硫酸盐降解2,4-DCP研究中。【结果】研究结果表明,Co_(3)O_(4)被均匀的涂覆在具有规则骨架结构的碳纤维表面,在Co(Ⅱ)-π的相互作用下形成了富电子钴中心和贫电子碳中心。在pH值为3.0~7.8,2,4-DCP的质量浓度为50mg/L,Co_(3)O_(4)@CF质量浓度为0.1g/L,PMS浓度为10mmol/L的初始条件下,Co_(3)O_(4)@CF在20min内可实现2,4-DCP的完全降解。在此过程中,Co_(3)O_(4)@CF可诱导反应体系中电子从贫电子中心向富电子中心转移,实现Co_(3+)的快速还原和PMS的快速活化。表征结果也进一步证明,碳纤维不仅可以作为载体,还可以通过其结构缺陷参与过硫酸盐活化的链式自由基反应,从而促进SO_(4)^(-)·转换为1O_(2)和O_(2)^(-)·,达到高效降解2,4-DCP的目的。 展开更多
关键词 碳纤维 Co_(3)O_(4) 贫/富电子中心 2 4-二氯酚 催化降解
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共同富裕:从马克思的现代性批判到中国式现代化
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作者 徐亮 《岭南学刊》 2024年第4期72-81,共10页
贫富分化是资本主义现代性危机的重要表征,也是马克思现代性批判的重要切入点。马克思揭示了以生产资料私人占有制为基础的资本主义现代化必然造成劳动与财产、劳动与所有权的内在分离,使得“生产和社会福利的这两个杠杆不能结合起来”... 贫富分化是资本主义现代性危机的重要表征,也是马克思现代性批判的重要切入点。马克思揭示了以生产资料私人占有制为基础的资本主义现代化必然造成劳动与财产、劳动与所有权的内在分离,使得“生产和社会福利的这两个杠杆不能结合起来”,进而导致贫富分化的现代性困境,并使现代文明有陷入堕落境遇的危险。为此,马克思建构了一种以“所有的人富裕”为本质规定之一的社会主义现代性,它是对以贫富分化为重要表征的资本主义现代性危机的积极扬弃,指向超越整个现代性本身并创造一种新文明类型的终极目标。在中国式现代化的历史性实践中,中国共产党人将马克思现代性思想运用于中国现实场域并同中华优秀传统文化相结合,创造性地提出了“共同富裕”这一作为中国式现代化本质要求之一的理念与目标,不断推进与拓展中国式现代化,并为以共同富裕为重要标识之一的人类文明新形态创造了现实可能性。 展开更多
关键词 现代性 贫富分化 共同富裕 中国式现代化 人类文明新形态
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富水粉细砂地层暗挖大断面地铁隧道地下水综合控制措施研究
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作者 黄刚 《江西建材》 2024年第1期173-175,共3页
文中依托北京地铁12号线三元桥站-芳园里站区间暗挖大断面停车线隧道工程,分析注浆试验段采用常规水泥-水玻璃双液浆进行超前深孔注浆存在的问题,提出并实施了渗透注浆与劈裂注浆相结合的复合式注浆方法,并基于数值计算结果,给出“最优... 文中依托北京地铁12号线三元桥站-芳园里站区间暗挖大断面停车线隧道工程,分析注浆试验段采用常规水泥-水玻璃双液浆进行超前深孔注浆存在的问题,提出并实施了渗透注浆与劈裂注浆相结合的复合式注浆方法,并基于数值计算结果,给出“最优深孔注浆厚度”概念,在此基础上确定本工程超前深孔注浆加固厚度,另外针对粉细砂层和粉质黏土层之间的层间水(三),深孔注浆后隧道开挖仍存在残留水问题,提出一种新型真空井点降水成孔方法,提高了成孔效率,确保了井点降水效果。 展开更多
关键词 富水粉细砂地层 渗透注浆 劈裂注浆 最优注浆厚度 井点降水 成孔方法
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元宇宙视域下贫富差距的问题分析和治理之策
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作者 沈先陈 《合肥大学学报》 2024年第3期79-86,共8页
元宇宙以前所未有的方式深层次地影响了人类社会,并可能导致人类社会的贫富差距进一步扩大。究其原因,元宇宙由于其经济技术和人员的门槛过高,容易导致资本垄断资源,并进一步加剧资本对劳动者的剥削,进而导致人类社会贫富差距拉大。有... 元宇宙以前所未有的方式深层次地影响了人类社会,并可能导致人类社会的贫富差距进一步扩大。究其原因,元宇宙由于其经济技术和人员的门槛过高,容易导致资本垄断资源,并进一步加剧资本对劳动者的剥削,进而导致人类社会贫富差距拉大。有鉴于此,出于对元宇宙发展带来的人类社会贫富差距的警思,应考虑以普惠发展来降低其门槛,以制度建构来规制资源合理分配,以技术和法律规制来削弱资本对劳动者的剥削,从而有效解决元宇宙发展带来的贫富差距问题,造福人类社会。 展开更多
关键词 元宇宙 贫富差距 虚拟世界 资源垄断 技术
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富水砂层短结构竖井盾构分体始发技术研究
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作者 刘炜龙 《工程技术研究》 2024年第2期91-93,共3页
为解决分体始发过程中因效率低造成施工风险大的问题,文章结合西安地铁14号线盾构在全断面富水砂层分体始发的工程实例,分析了满足盾构始发的最优结构尺寸,并确定了合理的分体始发程序及管线延长方案;根据施工需求,着重分析了盾构施工... 为解决分体始发过程中因效率低造成施工风险大的问题,文章结合西安地铁14号线盾构在全断面富水砂层分体始发的工程实例,分析了满足盾构始发的最优结构尺寸,并确定了合理的分体始发程序及管线延长方案;根据施工需求,着重分析了盾构施工的水平运输技术及始发过程中常见的技术问题与解决措施。 展开更多
关键词 富水砂层 短结构竖井 盾构分体始发技术
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Rejuvenation of Ovary and Thin Endometrium by Autologous PRP Injection in POR and Recurrent Implantation Failure 被引量:1
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作者 Yazhini Selvaraj Kanchana Malaisamy 《Advances in Sexual Medicine》 2021年第1期1-15,共15页
In India</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> the problem of infertility is growing and in the last 5 years</span><s... In India</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> the problem of infertility is growing and in the last 5 years</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> it has gone up to 20%</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">30%. This ongoing prospective clinical study brings forth a novel, innovative, effective, simple, affordable, easily performed outpatient procedure (OP) and a promising therapeutic method in rejuvenating the Ageing Ovaries and Thin Endometrium, with autologous Platelet Rich Plasma (PRP). This clinical study proves to give a better result in rejuvenating Ovary and treating the Thin Endometrium. This pilot study include</span><span style="font-family:Verdana;">d</span><span style="font-family:Verdana;"> five women (28</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">44 years) with Poor Ovarian Response (POR), Premature Ovarian Insufficiency (POI) and Perimenopause and Thirty-nine women (22</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">43</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">years.) with recurrent implantation failure due to Thin Endometrium were subjected to autologous PRP instillation under Ultrasound Guidance, and Hysteroscopic guided PRP. After PRP</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> a significant output was obtained, with improved Anti Mullerian Hormone (AMH) and Antral Follicle Count (AFC) and out of five women three women conceived by Intra Cytoplasmic Sperm Injection (ICSI). PRP injected in women with Poor Ovarian Response found successful ovarian rejuvenation within 1</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">3 months and had a 60% of pregnancy rate, PRP into the endometrium had 53.8% successful pregnancies. We have not encountered any complications. 展开更多
关键词 Platelet rich Plasma (PRP) poor Ovarian Reserve (POR) Premature Ovarian Insufficiency (POI) Anti Mullerian Hormone (AMH) Antral Follicle Counts (AFC) Intra Cytoplasmic Sperm Injection (ICSI) Outpatient Procedure (OP)
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Genetic causes of oil-rich and oil-poor reservoirs: Implications from two Cenozoic basins in the eastern North China Craton 被引量:2
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作者 Chiyang LIU Lei HUANG +4 位作者 Dongdong ZHANG Junfeng ZHAO Yu DENG Pei GUO Yijian HUANG &Jianqiang WANG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第12期1910-1931,共22页
The Bohai Bay and Hehuai(southern North China) rift basins in the eastern part of the North China Craton are southnorth-adjacent. They have shown synchronous evolutionary processes, and possess generally identical sup... The Bohai Bay and Hehuai(southern North China) rift basins in the eastern part of the North China Craton are southnorth-adjacent. They have shown synchronous evolutionary processes, and possess generally identical superficial and shallow structural characteristics as well as similar basin areas. However, there is a large difference in the richness of oil resources between the two basins. The Bohai Bay Basin has extremely abundant oil reserves, while commercial oil reserves have not been found in the Hehuai Basin. The deep tectonic structures, magmatic activities, and modern and paleo-geothermal fields of the two basins are significantly different. Compared with the Hehuai Basin, the Bohai Bay Basin has a thinner crust and more complex structure with multiple low-velocity layers. It is also characterized by intense magmatic activity, high modern and paleogeothermal fields, frequent seismic activity, and active deep interactions, small effective elastic thickness of the isotropic lithosphere, and shorter balanced transformation wavelength of the lithosphere with a high likelihood of local compensation. The Hehuai Basin has a simple deep structure and homogeneous crustal composition, with a high likelihood of regional compensation. The characteristics of the deep structures mentioned above are generally similar to those of the southern part of the stable Ordos Basin, except for the smaller crust thickness. This indicates the presence of differences in Mesozoic destruction between the southern and northern zones in the eastern part of the North China Craton. The northern zone was subjected to significant destruction, while the southern zone was subjected to modifications, primarily in the form of local changes in the structures and/or properties of the crust or lithospheric mantle, with the overall structure and stability of the craton kept intact. The formation of high-quality source rock is primarily influenced by the abnormal flourishment of organisms in water bodies during the syndepositional period, and is also strongly associated with the high geothermal setting of basins and nutrients from hydrothermal solutions and volcanoes. In other words, it is mainly controlled by deep processes and deep-major fault activity. The differences in the deep structures and modern and paleo geothermal fields of the two basins correspond to the difference in richness of oil resources, suggesting that there is an important internal or causal relationship between the two aspects. This viewpoint coincides with the conditions and environments required for the development of high-quality source rock in hydrocarbon-rich basins(sags)in China and other countries, and is evidenced by the modern lake basin of the East African Rift. A new hydrocarbon generation model is proposed in this work: petroleum is a comprehensive product of the integration of bioenergy, thermal energy, and other related energies(such as chemical and kinetic energy) and their interactions; the degree of richness of petroleum is generally controlled by the regional tectonic structure, thermal environment, and deep processes; nonmarine basins or depressions with abundant resources are closely related to active deep processes, intense exchange of material between the deep and shallow layers, participation of external hydrocarbons, and energy integration and conversion. 展开更多
关键词 GENETIC CAUSES of oil-rich and oil-poor RESERVOIRS Bohai Bay Basin Hehuai Basin Destruction of North China Craton Deep processes High-quality source rock formation
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普惠保险、人力资本投资与贫富差距 被引量:1
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作者 郑军 桂静怡 《河北农业大学学报(社会科学版)》 2023年第6期20-33,共14页
尝试构建包含普惠保险、人力资本投资与贫富差距的柯布道格拉斯生产函数研究框架,分析普惠保险通过人力资本投资缩小贫富差距并助推共同富裕的作用渠道与影响效应;基于熵权法构建普惠保险指数并结合中介效应模型,实证检验普惠保险的就... 尝试构建包含普惠保险、人力资本投资与贫富差距的柯布道格拉斯生产函数研究框架,分析普惠保险通过人力资本投资缩小贫富差距并助推共同富裕的作用渠道与影响效应;基于熵权法构建普惠保险指数并结合中介效应模型,实证检验普惠保险的就业效应与人力资本投资、增收效应与贫富差距间的相互关系。研究发现:普惠保险促进人力资本投资是缩小贫富差距并助推共同富裕的重要机制;普惠保险的公平性和市场性降低金融服务门槛,增加教育和技能培训机会,提高就业竞争力,产生就业效应;普惠保险的保障性与政策性有利于减少教育投资失败风险,增加居民教育投资意愿,提高教育投资回报率,产生增收效应;人力资本投资强化了普惠保险缩小贫富差距并助推共同富裕的作用;普惠保险对贫富差距的影响因教育投入水平不同而存在明显差异。对普惠保险的多维增收效应研究发现:普惠保险对低收入家庭相对收入与生活水平均有显著的正向作用。进一步研究发现:当教育投入与受教育水平越高时,普惠保险缩小贫富差距的影响更显著。 展开更多
关键词 普惠保险 人力资本投资 贫富差距
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富血小板血浆在生殖医学领域应用的研究进展
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作者 袁彩霞 杨欢 +1 位作者 宋海霞 范玲玲 《中国计划生育学杂志》 2023年第5期1242-1246,共5页
富血小板血浆(PRP)是一种高浓度血小板血浆,被应用于临床多个学科,本文旨在总结和评价PRP在生殖医学领域的作用,包括薄型子宫内膜、反复着床失败(RIF)、慢性子宫内膜炎和卵巢功能低下等方面,期望为PRP在生殖领域的临床治疗及未来的科学... 富血小板血浆(PRP)是一种高浓度血小板血浆,被应用于临床多个学科,本文旨在总结和评价PRP在生殖医学领域的作用,包括薄型子宫内膜、反复着床失败(RIF)、慢性子宫内膜炎和卵巢功能低下等方面,期望为PRP在生殖领域的临床治疗及未来的科学研究提供参考。 展开更多
关键词 富血小板血浆 薄型子宫内膜 复发性着床失败 慢性子宫内膜炎 卵巢功能低下
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技术之殇:两宋时期的农业减灾技术与救荒制度
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作者 金勇强 《农业考古》 北大核心 2023年第4期130-139,共10页
以农学、工学和生物防治技术为代表的农业减灾技术,在两宋灾荒救济中发挥着无可估量的作用但在官府救荒实践中,技术之外的蠲阁、灾赈等制度手段仍居于最核心和最根本的地位。一方面,传统农业减灾技术的革新过于缓慢,难以适应实际减灾需... 以农学、工学和生物防治技术为代表的农业减灾技术,在两宋灾荒救济中发挥着无可估量的作用但在官府救荒实践中,技术之外的蠲阁、灾赈等制度手段仍居于最核心和最根本的地位。一方面,传统农业减灾技术的革新过于缓慢,难以适应实际减灾需求;另一方面,减灾技术的革新与推广需要官府力量的推动,而两宋地方官员在此间所扮演的角色,更显得力不从心。劝农之制虽然为技术传播提供了一个制度平台,但传统官僚的劝农之为,更侧重于伦理教化之功,弱于技术的推广应用。当然,技术手段在传统救荒中的弱化,不仅仅是因为传统农业技术落后尚不能担当其救济灾荒的重任,更在于宋代贫富分化,土地兼并的现实。时势要求,宋代政府必须着眼于通过调节财富的分配,来缓解、消弭灾荒易造成动乱的社会危机。 展开更多
关键词 两宋时期 减灾技术 救荒制度 劝农 贫富分化
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