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Engineering Strategies for Suppressing the Shuttle Effect in Lithium–Sulfur Batteries 被引量:2
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作者 Jiayi li li gao +7 位作者 Fengying Pan Cheng Gong limeng Sun Hong gao Jinqiang Zhang Yufei Zhao Guoxiu Wang Hao liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期187-221,共35页
Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost.Nevertheless,the shuttle effect of firm multi-step two-elect... Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost.Nevertheless,the shuttle effect of firm multi-step two-electron reaction between sulfur and lithium in liquid electrolyte makes the capacity much smaller than the theoretical value.Many methods were proposed for inhibiting the shuttle effect of polysulfide,improving corresponding redox kinetics and enhancing the integral performance of Li–S batteries.Here,we will comprehensively and systematically summarize the strategies for inhibiting the shuttle effect from all components of Li–S batteries.First,the electrochemical principles/mechanism and origin of the shuttle effect are described in detail.Moreover,the efficient strategies,including boosting the sulfur conversion rate of sulfur,confining sulfur or lithium polysulfides(LPS)within cathode host,confining LPS in the shield layer,and preventing LPS from contacting the anode,will be discussed to suppress the shuttle effect.Then,recent advances in inhibition of shuttle effect in cathode,electrolyte,separator,and anode with the aforementioned strategies have been summarized to direct the further design of efficient materials for Li–S batteries.Finally,we present prospects for inhibition of the LPS shuttle and potential development directions in Li–S batteries. 展开更多
关键词 Shuttle effect Designed strategies Li-S battery Lithium polysulfides
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A novel live attenuated vaccine candidate protects chickens against subtype B avian metapneumovirus
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作者 lingzhai Meng Mengmeng Yu +15 位作者 Suyan Wang Yuntong Chen Yuanling Bao Peng liu Xiaoyan Feng Tana He Ru Guo Tao Zhang Mingxue Hu Changjun liu Xiaole Qi Kai li li gao Yanping Zhang Hongyu Cui Yulong gao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1658-1670,共13页
Avian metapneumovirus(aMPV) is a highly contagious pathogen that causes acute upper respiratory tract diseases in chickens and turkeys, resulting in serious economic losses. Subtype B aMPV has recently become the domi... Avian metapneumovirus(aMPV) is a highly contagious pathogen that causes acute upper respiratory tract diseases in chickens and turkeys, resulting in serious economic losses. Subtype B aMPV has recently become the dominant epidemic strain in China. We developed an attenuated aMPV subtype B strain by serial passaging in Vero cells and evaluated its safety and efficacy as a vaccine candidate. The safety test showed that after the 30th passage, the LN16-A strain was fully attenuated, as clinical signs of infection and histological lesions were absent after inoculation.The LN16-A strain did not revert to a virulent strain after five serial passages in chickens. The genomic sequence of LN16-A differed from that of the parent wild-type LN16(wtLN16) strain and had nine amino acid mutations. In chickens, a single immunization with LN16-A induced robust humoral and cellular immune responses, including the abundant production of neutralizing antibodies, CD4^(+) T lymphocytes, and the Th1(IFN-γ) and Th2(IL-4 and IL-6)cytokines. We also confirmed that LN16-A provided 100% protection against subtype B aMPV and significantly reduced viral shedding and turbinate inflammation. Our findings suggest that the LN16-A strain is a promising live attenuated vaccine candidate that can prevent infection with subtype B aMPV. 展开更多
关键词 avian metapneumovirus ATTENUATED protection vaccine candidate CHICKENS
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The impact of toroidal mode coupling on high-density discharges in J-TEXT
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作者 Peng DENG Wenzhe MAO +13 位作者 Zhipeng CHEN Yinan ZHOU Peng SHI Zhoujun YANG li gao Tao LAN Jinlin XIE Hong li Zian WEI Adi liU Chu ZHOU Weixing DING Wandong liU Ge ZHUANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第12期1-8,共8页
Density limit has long been a widely studied issue influencing the operating range of tokamaks.The rapid growth of the m/n=2/1(where m and n are poloidal and toroidal mode numbers,respectively)tearing mode is generall... Density limit has long been a widely studied issue influencing the operating range of tokamaks.The rapid growth of the m/n=2/1(where m and n are poloidal and toroidal mode numbers,respectively)tearing mode is generally regarded as a primary precursor to the density limit disruption.In this experiment,the coupling of the m/n=1/1 mode and the m/n=2/1 mode in highdensity plasma was observed.During a sawtooth cycle,the frequencies of the two modes gradually converge until they become equal.After that,toroidal coupling occurs between the 1/1 and 2/1 modes,resulting in a mutually fixed phase relationship.With the occurrence of toroidal coupling,the 2/1 mode is stabilized.Prior to the disruption,the cessation of the 1/1 and 2/1 mode coupling,along with the rapid growth in the amplitude of the 2/1 mode,can be observed.Additionally,under the same parameters,comparing discharges with or without the 1/1 mode,it is found that the presence of the 1/1 mode leads to higher plasma density and temperature parameters. 展开更多
关键词 toroidal coupling tearing mode density limit SAWTOOTH
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Experimental Investigations of Quasi-Coherent Micro-Instabilities in J-TEXT Ohmic Plasmas
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作者 石鹏 庄革 +5 位作者 程芝峰 高丽 周乙楠 刘永 罗景庭 李景春 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第5期47-52,共6页
Quasi-coherent micro-instabilities is one of the key topics of magnetic confinement fusion. This work focuses on the quasi-coherent spectra of ion temperature gradient(ITG) and trapped-electron-mode instabilities usin... Quasi-coherent micro-instabilities is one of the key topics of magnetic confinement fusion. This work focuses on the quasi-coherent spectra of ion temperature gradient(ITG) and trapped-electron-mode instabilities using newly developed far-forward collective scattering measurements within ohmic plasmas in the J-TEXT tokamak.The ITG mode is characterized by frequencies ranging from 30 to 100 k Hz and wavenumbers(k_(θρs)) less than 0.3. Beyond a critical plasma density threshold, the ITG mode undergoes a bifurcation, which is marked by a reduction in frequency and an enhancement in amplitude. Concurrently, enhancements in ion energy loss and degradation in confinement are observed. This ground-breaking discovery represents the first instance of direct experimental evidence that establishes a clear link between ITG instability and ion thermal transport. 展开更多
关键词 ITG mode COLLECTIVE
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Regional Brand and High-quality Development of Fruits in Ethnic Areas of the Yangtze River Economic Belt under the Greater Food Approach
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作者 li gao Jianjun ZHANG +2 位作者 Yuanpeng SUN Zhiyang liU Zhiguo SUN 《Asian Agricultural Research》 2024年第3期1-7,共7页
Establishing the Greater Food Approach and promoting the Yangtze River Economic Belt s national major regional development strategy can better support and serve the agricultural power and Chinese-style modernization.T... Establishing the Greater Food Approach and promoting the Yangtze River Economic Belt s national major regional development strategy can better support and serve the agricultural power and Chinese-style modernization.This paper introduces the characteristics of fruit industry in 16 autonomous prefectures and 47 autonomous counties under the jurisdiction of the Yangtze River Economic Belt.It studies the intellectual property resources of brand marks from the aspects of geographical indications,collective trademarks,certification trademarks,well-known trademarks in China and national design patents,and analyzes the main problems of brand and high-quality development of fruit industry in these ethnic autonomous areas.Finally,it puts forward some strategies,such as improving the protection of intellectual property rights of geographical indications,using intellectual property rights of brand signs,building modern seed industry upgrading project,drawing lessons from the experience of thousand villages demonstration project,ensuring that large-scale poverty does not occur,and building a diversified food supply system. 展开更多
关键词 GREATER FOOD APPROACH Fruit industry Regional brand The Yangtze River Economic Belt ETHNIC areas
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Thoughts on Pairing Assistance to Tibet for Promoting Agricultural High-quality Development in Southern Tibet from the Perspective of Agricultural Power
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作者 Zhiguo SUN li gao +3 位作者 Yuanpeng SUN Guangchao CAO Xinying ZHOU Xiaoqiang li 《Asian Agricultural Research》 2024年第3期18-24,共7页
In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style mod... In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style modernization.Southern Tibet,located in the southeastern part of the Tibet Autonomous Region,includes Shannan City and Nyingchi City,is a region assisted by four provincial partners including Hubei Province.This paper introduces the agricultural environment in southern Tibet,studies its agricultural characteristics,and analyzes the main issues of its pairing assistance.Taking forging the strong consciousness of the Chinese national community as the main line,the paper explores strategies for promoting agricultural high-quality development in southern Tibet through pairing assistance to Tibet from the perspective of agricultural power,and proposes some strategies,such as inheriting agricultural cultural heritage,promoting the upgrading of modern seed industry,enhancing the characteristic advantages of highland barley(naked barley)and animal husbandry industries,and developing edible fungi and cold water fish industries. 展开更多
关键词 PAIRING ASSISTANCE to TIBET Southern TIBET Shannan CITY Nyingchi CITY AGRICULTURAL high-quality development AGRICULTURAL power
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Promoting High-quality Development of Grain and Oil in Ethnic Areas of the Yangtze River Economic Belt from the Perspective of Agricultural Power
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作者 li gao Jianjun ZHANG +2 位作者 Yuanpeng SUN Zhiyang liU Zhiguo SUN 《Asian Agricultural Research》 2024年第2期1-7,11,共8页
Accelerating the construction of agricultural power,further promoting the high-quality development of the Yangtze River Economic Belt,and better supporting and serving Chinese-style modernization are the key issues at... Accelerating the construction of agricultural power,further promoting the high-quality development of the Yangtze River Economic Belt,and better supporting and serving Chinese-style modernization are the key issues at present.This paper first introduces the Yangtze River Economic Belt and its ethnic areas,and studies the characteristics of the grain and oil industry in the ethnic autonomous areas of the economic belt,as well as the current situation of various types of intellectual property resources,such as industrial cultural heritage,scientific and tech-nological innovation,and brand marking intellectual property.Besides,it analyzes the main problems in the high-quality development of grain and oil in the Yangtze River Economic Belt ethnic areas.Finally,it comes up with recommendations,including protecting the intellectual prop-erty rights of cultural heritage in the field of grain and oil,leading the inheritance and development of excellent traditional Chinese culture,use scientific and technological innovation intellectual property rights to promote the innovation-driven development strategy of the grain and oil in-dustry,and providing counterpart assistance to ethnic autonomous areas in the Yangtze River Economic Belt to further promote the high-quality development of the Yangtze River Economic Belt. 展开更多
关键词 The Yangtze River Economic Belt Ethnic areas Grain and oil Intellectual property Agricultural power
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Geographical Indication Intellectual Property Protection and Regional Public Brand Construction of Rape Industry in China 被引量:7
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作者 li gao Yamin PENG +3 位作者 Leying WU Jin ZENG Yuanpeng SUN Zhiguo SUN 《Asian Agricultural Research》 2023年第6期7-13,共7页
As China s largest oil crop,rape occupies a central position in ensuring the safety of China s cooking oil supply.This paper introduced China s rapeseed industry from the rape type,rapeseed production,planting area,na... As China s largest oil crop,rape occupies a central position in ensuring the safety of China s cooking oil supply.This paper introduced China s rapeseed industry from the rape type,rapeseed production,planting area,national rapeseed production protected area,rape national dominant characteristic industrial clusters,and rapeseed industry,etc.Besides,from the aspects of geographical indication products,geographical indication trademarks,and geographical indications of agricultural products,this paper discussed the intellectual property protection of geographical indications of rape,rapeseed,and rapeseed oil in China.It analyzed the main problems such as the lag in the formulation of relevant standards for geographical indications and the low use of special signs for geographical indications,and finally came up with recommendations including building a public brand of geographical indications and expanding foreign exchanges of geographical indications. 展开更多
关键词 RAPE RAPESEED Rapeseed oil Geographical indication Regional public brand China
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Inheritance,Innovation and High-quality Development of Herbaceous Edible Oils in Hubei Province under the Strategy of Strengthening the Country with Intellectual Property 被引量:4
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作者 li gao Yuanpeng SUN +2 位作者 Jin ZENG Jianjun ZHANG Zhiguo SUN 《Asian Agricultural Research》 2023年第12期5-15,共11页
Only by improving the production capacity of domestic herbal edible oil can China ensure the safety of the supply chain of the important industrial chain of vegetable edible oil in China and practice the big food conc... Only by improving the production capacity of domestic herbal edible oil can China ensure the safety of the supply chain of the important industrial chain of vegetable edible oil in China and practice the big food concept.In addition to rice,maize,and soybean for using as grain and oil,there are eight kinds of herbaceous edible oil crops in Hubei Province,including rape,peanut,sesame,sunflower,perilla(perilla seed),cotton,linen and tiger nut(Cyperus esculentus).This paper studies the main industries of herbaceous edible oil crops and their intellectual property resources in Hubei Province,and analyzes the main problems of its inheritance,innovation and high-quality development under the strategy of strengthening the country with intellectual property.Finally,it proposes the countermeasures of carrying forward and inheriting traditional knowledge and traditional culture,maintaining the biodiversity of crops,strengthening the creation of new plant varieties and breeding patents,and opening up the whole chain of intellectual property rights. 展开更多
关键词 HERBACEOUS EDIBLE OIL crops Vegetable EDIBLE OIL Big food concept INTELLECTUAL property right HUBEI Province
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页岩-液体反应及其对地应力的影响
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作者 李皋 李泽 +2 位作者 胡嵩 李明昊 李卓阳 《西南石油大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第5期115-123,共9页
页岩地层钻完井过程中,页岩-液体反应难以避免。为研究页岩-液体反应机理及其对地应力分布的影响,选取川南地区龙马溪组页岩,开展了页岩-液体反应室内实验,明确了其反应机理及结果。在此基础上利用数值模拟技术研究了页岩-液体反应对地... 页岩地层钻完井过程中,页岩-液体反应难以避免。为研究页岩-液体反应机理及其对地应力分布的影响,选取川南地区龙马溪组页岩,开展了页岩-液体反应室内实验,明确了其反应机理及结果。在此基础上利用数值模拟技术研究了页岩-液体反应对地应力分布的影响。结果表明,页岩-液体反应将造成页岩损伤,衍生微裂缝,同时导致页岩的膨胀变形。页岩-液体反应将对应力分布状态产生影响,且影响程度与缝网复杂程度高度正相关。考虑页岩-液体反应后,压裂过程中地应力分布状态出现显著变化,并造成套管应力随页岩-液体作用时间增加,对套管变形产生影响。 展开更多
关键词 页岩-液体反应 页岩膨胀变形 地应力分布状态 套管变形
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Lycium ruthenicum Murr. treatment attenuates APP_(SWE)/PS1ΔE9 mouse model-like mitochondrial dysfunction in Slc25a46 knockout mouse model
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作者 Min Wang Tianxiong Xu +7 位作者 li gao Chujun Huang Piao Xu Congcong Gong William Kwame Amakye linfeng liao Maojin Yao Jiaoyan Ren 《Food Science and Human Wellness》 SCIE CSCD 2023年第5期1618-1625,共8页
Mitochondrial dysfunction is proposed to be substantially associated with ageing and ageing-related diseases like Alzheimer's disease(AD). However, it is unclear whether different mouse models with mitochondrialre... Mitochondrial dysfunction is proposed to be substantially associated with ageing and ageing-related diseases like Alzheimer's disease(AD). However, it is unclear whether different mouse models with mitochondrialrelated diseases have similar changes in mitochondrial morphology of the same tissues. Moreover, whether similarities in mitochondrial morphology can be a suitable marker for screening and/or discovering mitochondrial-protective substances remains unknown. Mitochondria morphology in different tissues of a novel mitochondrial outer membrane protein Slc25a46 knockout mouse and a traditional APP_(SWE)/PS1ΔE9 transgenic mouse were examined using transmission electron microscope(TEM). Both young Slc25a46 knockout mice and aged APP_(SWE)/PS1ΔE9 mice models showed similar mitochondrial damage in cerebellum tissues. The results indicated that different mitochondrial-related diseases shared similar alteration and defects in mitochondrial morphology. Furthermore, Lycium ruthenicum Murr. extract, a bioactive food substance with cognition-improving property, could effectively improve muscle strength and increase body weight in the Slc25a46 knockout mice. These findings suggest that mitochondrial morphology defects in mice models, particularly in the mitochondrial compartment, represent a unified and effective marker for screening and validating natural product-derived functional substances with mitochondrial protective properties. It also holds potential application in mitochondrial-impaired senile neurodegenerative diseases, especially in AD. 展开更多
关键词 Mitochondria dysfunction Ageing Slc25a46 knockout mouse Alzheimer’s disease Lycium ruthenicum Murr.
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基于SWOT分析的矿山生态修复治理EOD模式研究 被引量:1
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作者 李高 杨自安 +2 位作者 杜斌 初娜 裴森龙 《中国矿业》 北大核心 2024年第4期132-140,共9页
矿山的生态修复治理已成为亟需解决的生态环境和区域协调发展的关键难题。本文系统分析了政府和社会资本合作模式(Public-Private-Partnership,PPP模式)及工程总承包模式(Engineering-Procurement-Construction,EPC模式)在矿山生态修复... 矿山的生态修复治理已成为亟需解决的生态环境和区域协调发展的关键难题。本文系统分析了政府和社会资本合作模式(Public-Private-Partnership,PPP模式)及工程总承包模式(Engineering-Procurement-Construction,EPC模式)在矿山生态修复治理中的现状,并基于SWOT分析法梳理出生态环境导向的矿山生态修复治理开发模式(Eco-environment-oriented Development,EOD模式)下矿山修复的内在优劣势和外部的机遇与挑战。研究结果表明,EOD模式可以很好地吸纳EPC模式和PPP模式的优点,将矿山修复工作融合到区域经济发展中,EOD模式的优势表现在促进区域融合发展、加速土地指标流转、废弃资源综合利用、经济增长与环境保护相协调、缓解政府治理环境的压力、国家部门政策支持,以及环境治理资金投入不断加大等方面。EOD模式在矿山生态修复治理方面的劣势主要表现为对于区位优势不突出的矿山难以起到很好的融资效果,进而实现经济效益,并且在利益分配方面也面临着尾矿处置权益边界不清晰和国家在生态修复过程中的制度缺陷等问题。 展开更多
关键词 矿山生态修复 PPP模式 EPC模式 EOD模式 SWOT分析
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氮气钻井岩爆动力学演化机制的数值模拟及岩爆实录特征分析
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作者 罗成波 何龙 +5 位作者 蒋祖军 李皋 孟英峰 欧彪 严焱诚 谢平 《科学技术与工程》 北大核心 2024年第12期4925-4931,共7页
为了厘清氮气钻井井底岩爆动力学演化机理,应用多物理场耦合分析软件COMSOL Multiphysics 4.3,建立井底逐渐接近裂缝的数值模型,基于致密砂岩岩体内部微裂缝起裂时对应的等效塑性应变为判断标准,分别应用CWFS(cohesion weakening and fr... 为了厘清氮气钻井井底岩爆动力学演化机理,应用多物理场耦合分析软件COMSOL Multiphysics 4.3,建立井底逐渐接近裂缝的数值模型,基于致密砂岩岩体内部微裂缝起裂时对应的等效塑性应变为判断标准,分别应用CWFS(cohesion weakening and frictional strengthening)-DP(Drucker-Prager)内聚力弱化摩擦力强度准则、DP强度准则及MC(Mohr-Coulomb)强度准则进行平行数值计算,得出了氮气钻井井底岩爆的动态演化过程。结果表明:井底逐渐靠近裂缝过程中致密砂岩基质会产生两种不同的破坏方式,即是沿着潜在剪切面,向井筒剪切滑移破坏及应力集中条件下的微剪切方式的挤压屈服破坏,直至破坏区延伸连通低压井筒,裂缝内的高压气体及岩爆碎屑释放大量能量,产生井底岩爆。研究成果可系统解释X8-2井井底岩爆发生前后随钻监测参数的异常变化,为准确判断氮气钻井井下工况提供了理论支撑,同时为及时采取针对性的对策措施提供了依据。 展开更多
关键词 氮气钻井 岩爆 动力学演化 数值模拟 岩爆实录
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气体钻井高效开发致密砂岩气藏的典型案例分析
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作者 李皋 张毅 +3 位作者 杨旭 胥志雄 何龙 龚汉渤 《钻采工艺》 CAS 北大核心 2024年第1期30-38,I0001,共10页
目前气体钻井开发致密砂岩气藏是否高效建产受多方面制约,建产机理尚不清晰,阻碍了气体钻井发挥技术优势。为此,文章选取塔里木迪北地区和川西地区的典型高产井为研究对象,在综合分析随钻资料的基础上,探究了高效建产的共性特征。研究发... 目前气体钻井开发致密砂岩气藏是否高效建产受多方面制约,建产机理尚不清晰,阻碍了气体钻井发挥技术优势。为此,文章选取塔里木迪北地区和川西地区的典型高产井为研究对象,在综合分析随钻资料的基础上,探究了高效建产的共性特征。研究发现,产气点的井深与砂泥岩岩性界面存在高度相关性,证实了岩性界面处发育的缝网系统是有利渗流通道;有水致密气藏中,受断裂带影响,地层水在断层下降盘上部富集概率高,部署在断层上升盘的井产水程度低,加之岩性界面缝的存在,使气水实现同产、稳产。分析认为,井位部署应以构造高部位和断层上升盘为依据,确保气源富集的同时避免水体突进,井轨迹应将岩性界面缝作为重点穿越目标,上部井段下套管应避免完全封隔目的层泥岩段,以充分释放岩性界面缝的产气潜力。未来还应加强技术攻关,提升气体钻井钻穿复杂砂泥岩互层的能力。 展开更多
关键词 致密砂岩气藏 气体钻井 岩性界面缝 井位部署
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基于三维地质力学的压力剖面钻前预测研究
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作者 白鸣生 杨旭 +3 位作者 上官自然 李皋 郭建华 王秋彤 《中国安全生产科学技术》 CAS CSCD 北大核心 2024年第7期87-93,共7页
为解决目前基于邻井测井资料评价得到的压力剖面与待钻井实际井轨迹上的结果不符等问题,提出基于三维地质力学的待钻井井眼轨迹上的压力剖面钻前预测方法。以地震解释的层位数据为基础,结合断层数据、钻井分层数据等构建三维地质模型。... 为解决目前基于邻井测井资料评价得到的压力剖面与待钻井实际井轨迹上的结果不符等问题,提出基于三维地质力学的待钻井井眼轨迹上的压力剖面钻前预测方法。以地震解释的层位数据为基础,结合断层数据、钻井分层数据等构建三维地质模型。然后,利用已钻井测井数据,通过序贯高斯插值法获得三维岩石力学参数场,并且通过有限元数值模拟得到区域地应力以及压力系统,进而获得待钻井井眼轨迹上的压力剖面。研究结果表明:该方法预测精度较高,已钻井的孔隙压力预测值与实测值的误差为3.57%,地应力预测值与实测值误差为5.8%。现场2口井的预测层位与实钻层位吻合程度较高,预测的三压力剖面能够较好地解释实钻过程中出现的井下复杂问题。研究结果可为钻前地质工程设计、井身结构优化、井下复杂问题预防等提供较为可靠的数据参考。 展开更多
关键词 地质力学 压力剖面 钻前预测 井眼轨迹 测井
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气体钻井岩屑含水量快速检测系统
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作者 李田禹 朱睿 +6 位作者 陈向东 丁星 夏文鹤 李皋 陈一健 苟浩淞 黄维尧 《仪表技术与传感器》 CSCD 北大核心 2024年第8期45-52,共8页
针对目前钻井现场检测地层出水的方法速度慢、抗干扰能力弱的问题,利用近红外光在水中具有显著的吸收特性,提出了一种基于近红外图像的岩屑含水量快速检测系统。系统利用940 nm波段的近红外摄像头采集图像,消除可见光干扰,提高了检测的... 针对目前钻井现场检测地层出水的方法速度慢、抗干扰能力弱的问题,利用近红外光在水中具有显著的吸收特性,提出了一种基于近红外图像的岩屑含水量快速检测系统。系统利用940 nm波段的近红外摄像头采集图像,消除可见光干扰,提高了检测的灵敏度。借助基于小波变换的滤波算法有效去除图像中的散射噪声,并采用区域生长算法进行图像分割,排除干扰物,避免误分割情况,提升系统的抗干扰能力。此外,运用HDBSCAN聚类算法快速精确提取岩屑区域,获取岩屑图像的灰度平均值。最后,利用分段线性回归算法构建了灰度值-含水量模型,预测岩屑含水量。实验结果表明:系统在复杂的天然气钻井环境中工作有效,最大绝对误差为1.87%,精度较高。平均检测时间不超过6 s,速度较快。相较于烘干法,系统在保证准确率的基础上显著提高了检测速度。与湿度传感器相比,系统不仅具有更高的检测精度,还能覆盖更大面积岩屑的水分检测需求。 展开更多
关键词 气体钻井 岩屑含水量 近红外图像 HDBSCAN聚类
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探究减瘤手术对合并远处转移的上尿路尿路上皮癌患者预后的影响
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作者 赵昱 张荣杰 +3 位作者 陈元浩 李高 矫宾宾 张鑫 《首都医科大学学报》 CAS 北大核心 2024年第2期340-347,共8页
目的探究减瘤手术对合并远处转移的上尿路尿路上皮癌患者预后的影响。方法筛选2010年1月至2015年12月SEER数据库中已经发生远处转移的上尿路尿路上皮癌患者的临床数据,根据是否行减瘤手术分为减瘤手术组和未做减瘤手术组,比较组间基线... 目的探究减瘤手术对合并远处转移的上尿路尿路上皮癌患者预后的影响。方法筛选2010年1月至2015年12月SEER数据库中已经发生远处转移的上尿路尿路上皮癌患者的临床数据,根据是否行减瘤手术分为减瘤手术组和未做减瘤手术组,比较组间基线差异。通过单因素和多因素Cox比例风险回归模型分析与已经发生远处转移的上尿路尿路上皮癌患者生存有关的预后影响因素。通过Kaplan-Meier法绘制生存曲线分析各组的生存情况。结果本研究共纳入患者238例,减瘤手术者157例,未做减瘤手术者81例,总体基线较为平稳。单因素和多因素Cox回归分析结果显示:减瘤手术、化学药物治疗(以下简称化疗)、肝转移是总生存期(overall survival,OS)的独立风险因素;减瘤手术和化疗是癌症特异性生存期(cancer special survival,CSS)的独立风险因素。Kaplan-Meier曲线显示:年龄、减瘤手术、化疗、肝转移与OS密切相关;减瘤手术、化疗、肝转移与CSS密切相关。结论对于已经发生远处转移的上尿路尿路上皮癌患者,减瘤手术可明显改善患者预后,减瘤手术、化疗、肝转移是总生存结局的独立影响因素,减瘤手术和化疗是疾病相关生存结局的独立影响因素。 展开更多
关键词 上尿路尿路上皮癌 远处转移 减瘤手术 预后 SEER
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Expert consensus on pediatric orthodontic therapies of malocclusions in children 被引量:1
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作者 Chenchen Zhou Peipei Duan +22 位作者 Hong He Jinlin Song Min Hu Yuehua liu Yan liu Jie Guo Fang Jin Yang Cao lingyong Jiang Qingsong Ye Min Zhu Beizhan Jiang Wenhua Ruan Xiao Yuan Huang li Rui Zou Yulou Tian li gao Rui Shu Jianwei Chen Renkai liu Shujuan Zou Xiaobing li 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第2期186-196,共11页
Malocclusion,identified by the World Health Organization(WHO)as one of three major oral diseases,profoundly impacts the dental-maxillofacial functions,facial esthetics,and long-term development of~260 million children... Malocclusion,identified by the World Health Organization(WHO)as one of three major oral diseases,profoundly impacts the dental-maxillofacial functions,facial esthetics,and long-term development of~260 million children in China.Beyond its physical manifestations,malocclusion also significantly influences the psycho-social well-being of these children.Timely intervention in malocclusion can foster an environment conducive to dental-maxillofacial development and substantially decrease the incidence of malocclusion or reduce the severity and complexity of malocclusion in the permanent dentition,by mitigating the negative impact of abnormal environmental influences on the growth.Early orthodontic treatment encompasses accurate identification and treatment of dental and maxillofacial morphological and functional abnormalities during various stages of dental-maxillofacial development,ranging from fetal stages to the early permanent dentition phase.From an economic and societal standpoint,the urgency for effective early orthodontic treatments for malocclusions in childhood cannot be overstated,underlining its profound practical and social importance.This consensus paper discusses the characteristics and the detrimental effects of malocclusion in children,emphasizing critical need for early treatment.It elaborates on corresponding core principles and fundamental approaches in early orthodontics,proposing comprehensive guidance for preventive and interceptive orthodontic treatment,serving as a reference for clinicians engaged in early orthodontic treatment. 展开更多
关键词 PERMANENT stated CHILDREN
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Scientific Advances and Weather Services of the China Meteorological Administration’s National Forecasting Systems during the Beijing 2022 Winter Olympics
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作者 Guo DENG Xueshun SHEN +23 位作者 Jun DU Jiandong GONG Hua TONG liantang DENG Zhifang XU Jing CHEN Jian SUN Yong WANG Jiangkai HU Jianjie WANG Mingxuan CHEN Huiling YUAN Yutao ZHANG Hongqi li Yuanzhe WANG li gao li SHENG Da li li li Hao WANG Ying ZHAO Yinglin li Zhili liU Wenhua GUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期767-776,共10页
Since the Beijing 2022 Winter Olympics was the first Winter Olympics in history held in continental winter monsoon climate conditions across complex terrain areas,there is a deficiency of relevant research,operational... Since the Beijing 2022 Winter Olympics was the first Winter Olympics in history held in continental winter monsoon climate conditions across complex terrain areas,there is a deficiency of relevant research,operational techniques,and experience.This made providing meteorological services for this event particularly challenging.The China Meteorological Administration(CMA)Earth System Modeling and Prediction Centre,achieved breakthroughs in research on short-and medium-term deterministic and ensemble numerical predictions.Several key technologies crucial for precise winter weather services during the Winter Olympics were developed.A comprehensive framework,known as the Operational System for High-Precision Weather Forecasting for the Winter Olympics,was established.Some of these advancements represent the highest level of capabilities currently available in China.The meteorological service provided to the Beijing 2022 Games also exceeded previous Winter Olympic Games in both variety and quality.This included achievements such as the“100-meter level,minute level”downscaled spatiotemporal resolution and forecasts spanning 1 to 15 days.Around 30 new technologies and over 60 kinds of products that align with the requirements of the Winter Olympics Organizing Committee were developed,and many of these techniques have since been integrated into the CMA’s operational national forecasting systems.These accomplishments were facilitated by a dedicated weather forecasting and research initiative,in conjunction with the preexisting real-time operational forecasting systems of the CMA.This program represents one of the five subprograms of the WMO’s high-impact weather forecasting demonstration project(SMART2022),and continues to play an important role in their Regional Association(RA)II Research Development Project(Hangzhou RDP).Therefore,the research accomplishments and meteorological service experiences from this program will be carried forward into forthcoming highimpact weather forecasting activities.This article provides an overview and assessment of this program and the operational national forecasting systems. 展开更多
关键词 Beijing Winter Olympic Games CMA national forecasting system data assimilation ensemble forecast bias correction and downscaling machine learning-based fusion methods
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Influence of perinatal factors on full-term low-birth-weight infants and construction of a predictive model
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作者 liang Xu Xue-Juan Sheng +4 位作者 lian-Ping Gu Zu-Ming Yang Zong-Tai Feng Dan-Feng Gu li gao 《World Journal of Clinical Cases》 SCIE 2024年第26期5901-5907,共7页
BACKGROUND Being too light at birth can increase the risk of various diseases during infancy.AIM To explore the effect of perinatal factors on term low-birth-weight(LBW)infants and build a predictive model.This model ... BACKGROUND Being too light at birth can increase the risk of various diseases during infancy.AIM To explore the effect of perinatal factors on term low-birth-weight(LBW)infants and build a predictive model.This model aims to guide the clinical management of pregnant women’s healthcare during pregnancy and support the healthy growth of newborns.METHODS A retrospective analysis was conducted on data from 1794 single full-term pregnant women who gave birth.Newborns were grouped based on birth weight:Those with birth weight<2.5 kg were classified as the low-weight group,and those with birth weight between 2.5 kg and 4 kg were included in the normal group.Multiple logistic regression analysis was used to identify the factors influencing the occurrence of full-term LBW.A risk prediction model was established based on the analysis results.The effectiveness of the model was analyzed using the Hosmer–Leme show test and receiver operating characteristic(ROC)curve to verify the accuracy of the predictions.RESULTS Among the 1794 pregnant women,there were 62 cases of neonatal weight<2.5 kg,resulting in an LBW incidence rate of 3.46%.The factors influencing full-term LBW included low maternal education level[odds ratio(OR)=1.416],fewer prenatal examinations(OR=2.907),insufficient weight gain during pregnancy(OR=3.695),irregular calcium supplementation during pregnancy(OR=1.756),and pregnancy hypertension syndrome(OR=2.192).The prediction model equation was obtained as follows:Logit(P)=0.348×maternal education level+1.067×number of prenatal examinations+1.307×insufficient weight gain during pregnancy+0.563×irregular calcium supplementation during pregnancy+0.785×pregnancy hypertension syndrome−29.164.The area under the ROC curve for this model was 0.853,with a sensitivity of 0.852 and a specificity of 0.821.The Hosmer–Leme show test yieldedχ^(2)=2.185,P=0.449,indicating a good fit.The overall accuracy of the clinical validation model was 81.67%.CONCLUSION The occurrence of full-term LBW is related to maternal education,the number of prenatal examinations,weight gain during pregnancy,calcium supplementation during pregnancy,and pregnancy-induced hypertension.The constructed predictive model can effectively predict the risk of full-term LBW. 展开更多
关键词 Pregnant women Perinatal care Low-birth-weight infants Influencing factors Prediction model
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