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Effect of Skeleton Grain Size on the Saturation of Gas Hydrate in Natural Sediments

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Journal of Ocean University of China 2024年第3期23卷 676-682页

作者： xu zhenqiang LI Yang College of Marine Sciences Ocean University of ChinaQingdao 266100China China Petroleum&Chemical Corporation Beijing 100728China

Natural gas hydrate is prospected as a new and promising,highly clean energy resource that mainly occurs in perma-frost or at continental margins.Its formation is subject to many soil conditions,such as grain size,matrix materials,pore morphology,and permeability.In this study,we propose that grain size is the most decisive parameter that affects the saturation of gas hydrate in sediments based on data from Ocean Drilling Program Leg 164 and Mallik 5L-38,which represent marine sediments and terrestrial sediments,respectively.Our study reveals that high gas hydrate saturation generally occurs in coarse-grained sand,regardless of whether sediment formation is homogeneous or inhomogeneous,and the sorting of sediments may affect the hydrate saturation to a certain degree.Using grain size and sorting of sediments may be the most intuitive proxy method for a rough estimation of hydrate saturation.Further study is necessary to fully understand the relationship between hydrate morphology and sediment grain size,even though massive hydrates are typically found in fine clayey-rich sediments.

关键词： grain size saturation gas hydrates ODP Leg 164 Mallik 5L-38

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Peroxyacetyl nitrate observed in Beijing in August from 2005 to 2009

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Journal of Environmental Sciences 2014年第10期26卷 2007-2017页

作者： Tianyu Gao Li Han Bin Wang Guang Yang zhenqiang xu Limin Zeng Jianbo Zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University

Measurements of peroxyacetyl nitrate（PAN） were made at a Beijing urban site each August from2005 to 2009. Over this 5-year period, the average PAN concentration for August in each year increased from 3（2005） to 11.7 μg/m3（2007）; however, it decreased rapidly in 2008（4.1 μg/m3）.Generally, the variation over the 5 years showed a rise in the first part of the study period,followed by a decline. We considered two categories of local and regional air masses in this study, which revealed that the PAN concentration in Beijing was affected mainly by southeastern air masses. The August PAN variation was influenced predominantly by local air masses in 2005,but by 2009 regional air masses had become more important. This study showed the level and variation of PAN in the month of August in 5 consecutive years for the first time, and proved that control measures are useful in decreasing photochemical pollution; hence, these measures are probably feasible for other megacities too. Furthermore, this method of analyzing regional and local impacts might be useful for other studies as well.

关键词： PAN Beijing Transport Local Regional

Feed conversion ratio,residual feed intake and cholecystokinin type A receptor gene polymorphisms are associated with feed intake and average daily gain in a Chinese local chicken population

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Journal of Animal Science and Biotechnology 2018年第4期9卷 794-802页

作者： Zhenhua Yi Xing Li Wen Luo zhenqiang xu Congliang Ji Yan Zhang Qinghua Nie Dexiang Zhang Xiquan Zhang Department of Animal Genetics Breeding and ReproductionCollege of Animal ScienceSouth China Agricultural UniversityGuangzhou 510642GuangdongChina Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding and Key Laboratory of Chicken Genetics Breeding and ReproductionMinistry of AgricultureGuangzhou 510642GuangdongChina Wen’s Nanfang Poultry Breeding Co.Ltd Yunfu 527400GuangdongChina

Background: The feed conversion ratio(FCR) and residual feed intake(RFI) are common indexes in measuring feed efficiency for livestock. RFI is a feed intake adjusted for requirements for maintenance and production so these two traits are related. Similarly, FCR is related to feed intake and weight gain because it is their ratio. Cholecystokinin type A receptor(CCKAR) plays an important role in animal digestive process. We examined the interplay of these three parameters in a local Chinese chicken population.Results: The feed intake(FI) and body weights(BW) of 1,841 individuals were monitored on a daily basis from 56 to 105 d of age. There was a strong correlation between RFI and average daily feed intake(ADFI) and a negative correlation between the FCR and daily gain(r_g=-0.710). Furthermore, we identified 51 single nucleotide polymorphisms(SNPs) in the CCKAR and 4 of these resulted in amino acid mutations. The C334A mutation was specifically associated with FI and the expected feed intake(EFI)(P < 0.01) and significantly associated with the average daily gain(ADG)(P < 0.05). G1290A was significantly associated with FI and EFI(P < 0.05).Conclusion: FCR is apply to weight selecting, and RFI is more appropriate if the breeding focus is feed intake. And C334A and G1290A of the CCKAR gene can be deemed as candidate markers for feed intake and weight gain.

关键词： CCKAR Chicken FCR RFI SNP

Dual-additives enable stable electrode-electrolyte interfaces for long life Li-SPAN batteries

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Chinese Chemical Letters 2024年第5期35卷 459-465页

作者： zhenqiang Guo Huicong Yang Qian Wei Shengjun xu Guangjian Hu Shuo Bai Feng Li School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Biochemistry and Molecular Biology College of Life ScienceChina Medical UniversityShenyang 110122China Dalian National Laboratory for Clean Energy Dalian 116023China Shenyang King Power Technology Co. Ltd.Shenyang 110016China

Sulfurized polyacrylonitrile(SPAN)is proposed as a promising cathode material for lithium sulfur batteries.However,the continuous side reactions at the electrolyte-electrode interfaces as well as the slow redox kinetics of SPAN cathode deteriorate the electrochemical performance.In this study,an electrolyte with dual-additives comprising 2-fluoropyridine(2-FP)and lithium difluorobis(oxalato)phosphate(LiDFBOP)was used to improve the performance of Li||SPAN cells.2-FP has a lower lowest occupied molecular orbital energy than that of the solvents in the electrolyte,leading to its prior reduction.A LiF-rich film can be formed on the electrode,effectively improving the stability of the electrolyte-electrode interfaces and prolonging the life.Simultaneously,LiDFBOP could form an electrolyte-electrode interface film containing a large amount of Li_(x)PO_(y)F_(z) species,compensating for the kinetic deterioration caused by the lower ionic conductive of LiF formed at the electrolyte-electrode interface.Hence,an electrode-interface film with good chemical stability and high Li^(+) transport was established by LiF and Li_(x)PO_(y)F_(z)-rich species.The Li||SPAN cell with the electrolyte containing dual-additives demonstrates an excellent capacity retention of 97.5%after 200 cycles at 1.0 C,25℃,comparing to 56.2%capacity retention without additives.Moreover,the rate capacities of cells with dual-additives can reach 1128.1 mAh/g at 5 C,comparing to only 813.5 mAh/g using electrolyte without additives.Our results shown that the dual-additives in electrolyte provide a promising strategy for practical application of lithium sulfur batteries with SPAN cathodes.

关键词： Sulfurized polyacrylonitrile Lithium metal Interface film 2-Fluoropyridine Difluorobis(oxalato)phosphate

Wind-sand flow simulation and radius optimization of highway embankment under different vertical curve radius

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Journal of Mountain Science 2024年第8期 2533-2546页

作者： LI Liangying LI Qi WANG xu XIN Guowei WANG zhenqiang School of Civil Engineering Lanzhou Jiaotong University

It is of great practical value to explore the correlation between the vertical curve radius of desert highway and the increase of sand accumulation in local lines, and to select the appropriate vertical curve radius for reducing the risk of sand accumulation. In this study, three-dimensional models of desert highway embankments with different vertical curve radii were constructed, and Fluent software was used to simulate the wind-sand flow field and sand accumulation distribution of vertical curve embankments. The results show that:(1) Along the direction of the road, the concave and the convex vertical curve embankments have the effect of collecting and diverging the wind-sand flow, respectively. When the radius of the concave vertical curve is 3000 m, 5000 m, 8000 m, 10000 m and 20000 m, the wind velocity in the middle of the vertical curve is 31.76%, 22.58%, 10.78%, 10.53% and 10.44%, higher than that at both ends. When the radius of the convex vertical curve is 6500 m, 8000 m, 10000 m, 20000 m and 30000 m, the wind velocity at both ends of the vertical curve is 14.06%, 9.99%, 6.14%, 3.22% and 2.41%, higher than that in the middle. The diversion effect also decreases with the increase of the radius.(2) The conductivity of the concave and convex vertical curve embankments with different radii is greater than 1, which is the sediment transport roadbed. The conductivity increases with the increase of radius and gradually tends to be stable. When the radius of the concave and convex vertical curves reaches 8000 m and 20000 m respectively, the phenomenon of sand accumulation is no longer serious. Under the same radius condition, the concave vertical curve embankment is more prone to sand accumulation than the convex one.(3) Considering the strength of the collection and diversion of the vertical curve embankment with different radii, and the sand accumulation of the vertical curve embankment in the desert section of Wuma Expressway, the radius of the concave vertical curve is not less than 8000 m, and the radius of

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ImmunoCytTM and cytology for diagnosis of bladder carcinoma：a meta analysis

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Chinese Medical Journal 2014年第4期127卷 758-764页

作者： Yang Minggen Zheng Zhouda Zhuang Zhiming Zhao Xiaokun xu zhenqiang Lin Haili Department of Urology Zhangzhou Affiliated Hospital Fujian Medical University Zhangzhou Fujian 363000 China Department of Urology The Second Xiangya Hospital Central South University Changsha Hunan 410011 China

Background Currently,cystoscopy and urine cytology are standard modalities in therapy monitoring and follow-up of bladder carcinoma （BC）.Cystoscopy is an invasive and uncomfortable procedure while cytology has a limited value because it is operator-dependent and has low sensitivity.This study was to assess the accuracy of ImmunoCyt in detecting BC by comparing it with cytology using systemic analyses of studies published in both English and Chinese.Methods Cochrane systematic evaluation was used to search through MEDLINE,EMBASE,Cochrane Library,CMCC,and CNKI for studies regarding ImmunoCyt and cytology for detection of BC.Data were extracted and analyzed by the software MetaDiSc 1.4.Results In total 42 relevant studies were searched,of which 15 were enrolled and 12 491 patients were included.Heterogeneity,except for threshold effects,was found within these studies.A meta-analysis was performed using the random effect model.Pooled accuracy indicators like sensitivity,specificity,and diagnostic odds ratio of ImmunoCytTM and cytology were 0.75 （0.73-0.77） vs.0.45 （0.43-0.48）,0.73 （0.72-0.74） vs.0.97 （0.96-0.97）,and 10.97 （7.53-15.99） vs.16.40 （10.57-25.46）,respectively.The sensitivity of both was increased with the increase of tumor grade and stage.The area under summary receiver operating characteristics curve was 0.834 4 and 0.853 4 and the Q index 0.766 7 and 0.785 3 for ImmunoCyt and cytology,respectively.Combination of both can obviously improve the accuracy of diagnosis.Conclusions ImmunoCyt has a high sensitivity in detecting BC,but its specificity is low.As an important adjunct,ImmunoCytTM can not replace cytology,but combined with cytology it could improve sensitivity with high specificity in the detection and postoperative monitoring of BC.

关键词： bladder carcinoma ImmunoCytTM cytology

A high-speed true random number generator based on Ag/SiNx/n-Si memristor

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Frontiers of physics 2024年第1期19卷 241-250页

作者： Xiaobing Yan Zixuan Zhang Zhiyuan Guan Ziliang Fang Yinxing Zhang Jianhui Zhao Jiameng Sun xu Han Jiangzhen Niu Lulu Wang Xiaotong Jia Yiduo Shao Zhen Zhao zhenqiang Guo Bing Bai Institute of Life Science and Green Development Key Laboratory of Brain-Like Neuromorphic Devices and Systems of Hebei ProvinceCollege of Electron and Information EngineeringHebei UniversityBaoding 071002China

The intrinsic variability of memristor switching behavior can be used as a natural source of randomness,this variability is valuable for safe applications in hardware,such as the true random number generator(TRNG).However,the speed of TRNG is still be further improved.Here,we propose a reliable Ag/SiNx/n-Si volatile memristor,which exhibits a typical threshold switching device with stable repeat ability and fast switching speed.This volatile-memristor-based TRNG is combined with nonlinear feedback shift register(NFSR)to form a new type of high-speed dual output TRNG.Interestingly,the bit generation rate reaches a high speed of 112 kb/s.In addition,this new TRNG passed all 15 National Institute of Standards and Technology(NIST)randomness tests without post-processing steps,proving its performance as a hardware security application.This work shows that the SiNx-based volatile memristor can realize TRNG and has great potential in hardware network security.

关键词： volatile memristor true random number generator(TRNG) delay time threshold switching device

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天然气水合物资源发展历程及产业化前景

海洋经济 2022年第3期12卷 62-69页

作者：杨振许振强广州海洋地质调查局广州510075 南方海洋科学与工程广东省实验室(广州) 广州511458

天然气水合物是资源量丰富的高效清洁能源,美欧日等发达国家和地区高度重视天然气水合物产业化工作,纷纷投入巨资开展资源调查、钻探、试采及环境影响评价等系统研究,旨在加快抢占天然气水合物开发利用的科技制高点。我国海域天然气水... 详细信息

天然气水合物是资源量丰富的高效清洁能源,美欧日等发达国家和地区高度重视天然气水合物产业化工作,纷纷投入巨资开展资源调查、钻探、试采及环境影响评价等系统研究,旨在加快抢占天然气水合物开发利用的科技制高点。我国海域天然气水合物分布广、类型多、资源量大。自1999年开展调查以来,初步摸清了天然气水合物资源家底,成功实施了两次海域天然气水合物试采,实现了从“跟跑”到“领跑”的历史转变。实现天然气水合物高效开发是一项极为复杂的系统性工程,涉及勘查、环评、开发工程技术、储运销售、政策等各个环节,但随着技术的进步,实现产业化未来可期,将有力缓解能源资源短缺危机,提升社会绿色发展水平、保障国家能源战略安全,孕育新蓝色经济。

关键词：天然气水合物资源勘查评价试采产业化

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论保障性租赁住房公募REITs能力建设

中国名城 2022年第11期36卷 19-30页

作者：李沁伟徐振强曼彻斯特大学中国城市科学研究会全国市长研修学院(住房和城乡建设部干部学院)

2015年中央城市工作会议、2021年中央经济工作会议和2022年多次国务院常务会议,均对盘活存量资产提出明确要求,REITs(Real Estate Investment Trusts,不动产投资信托基金)是落实该要求的重要方式。自2021年起,我国启动REITs发行试点,截... 详细信息

2015年中央城市工作会议、2021年中央经济工作会议和2022年多次国务院常务会议,均对盘活存量资产提出明确要求,REITs(Real Estate Investment Trusts,不动产投资信托基金)是落实该要求的重要方式。自2021年起,我国启动REITs发行试点,截至2022年10月底,共有20支REITs成功发行,资产规模超过728.05亿元,涵盖保障性租赁住房、产业园区、高速公路、污水处理、仓储物流、垃圾焚烧发电等领域。《国务院办公厅关于进一步盘活存量资产扩大有效投资的意见》(国办发〔2022〕19号)指出,“助力盘活存量资产,拓宽保障性租赁住房建设的权益型资金来源,促进房地产市场平稳健康发展。”从保障性租赁住房REITs的概念、市场需求、发行必要性、可行性和发行能力建设进行论述,结合行业态势,提出我国发展保障性租赁住房公募REITs存在的问题和意见建议。

关键词： REITs 保障性租赁住房公募REITs 租赁住房市场发展