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Effect of land use on soil nematode community composition and co-occurrence network relationship

Journal of Integrative Agriculture 2024年第8期23卷 2807-2819页

作者： xiaotong Liu Siwei liang Yijia Tian xiao Wang Wenju liang xiaoke Zhang Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China Tillage and Cultivation Research Institute Liaoning Academy of Agricultural SciencesShenyang 110161China University of Chinese Academy of Sciences Beijing 100049China Key Lab of Conservation Tillage and Ecological Agriculture in Liaoning Province Shenyang 110016China

Land use influences soil biota community composition and diversity,and then belowground ecosystem processes and *** characterize the effect of land use on soil biota,soil nematode communities in crop land,forest land and fallow land were investigated in six regions of northern *** richness,diversity,abundance and biomass of soil nematodes was the lowest in crop *** richness and diversity of soil nematodes were 28.8and 15.1%higher in fallow land than in crop land,*** significant differences in soil nematode indices were found between forest land and fallow land,but their network keystone genera composition was *** the keystone genera,50%of forest land genera were omnivores-predators and 36%of fallow land genera were *** proportion of fungivores in forest land was 20.8%lower than in fallow *** network complexity and the stability were lower in crop land than forest land and fallow *** pH,NH_(4)^(+)-N and NO_(3)^(–)-N were the major factors influencing the soil nematode community in crop land while soil organic carbon and moisture were the major factors in forest *** nematode communities in crop land influenced by artificial management practices were more dependent on the soil environment than communities in forest land and fallow *** use induced soil environment variation and altered network relationships by influencing trophic group proportions among keystone nematode genera.

关键词： soil nematode trophic groups community composition co-occurrence network land use

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Research on casing deformation prevention technology based on cementing slurry system optimization

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Petroleum Science 2024年第2期21卷 1231-1240页

作者： Yan Yan Meng Cai Wen-Hai Ma xiao-Chuan Zhang Li-hong Han Yong-hong Liu State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials CNPC Tubular Goods Research InstituteXi©an710077ShaanxiChina College of Mechanical and Electrical Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province Chengdu610095SichuanChina CNPC Daqing Oilfield Company Daqing163453HeilongjiangChina

The casing deformation prevention technology based on the optimization of cement slurry is proposed to reduce the casing deformation of shale oil and gas wells during hydraulic fracturing. In this paper, the fracture mechanism of hollow particles in cement sheath was firstly analyzed by discrete element method, and the effect of hollow particles in cement on casing deformation was investigated by laboratory experiment method. Finally, field test was carried out to verify the improvement effect of the casing deformation based on cement slurry modification. The results show that the formation displacement can be absorbed effectively by hollow particles inside the cement transferring the excessive deformation away from casing. The particles in the uncemented state provide deformation space during formation slipping. The casing with diameter of 139.7 mm could be passed through by bridge plug with the diameter of 99 mm when the mass ratio of particle/cement reaches 1:4. According to the field test feedback, the method based on optimization of cement slurry can effectively reduce the risk of casing deformation, and the recommended range of hollow microbeads content in the cement slurry is between 15% and 25%.

关键词： Cement slurry Hollow ceramsite Casing deformation Formation slip Field test

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Lithiophilic CoF_(2)@C hollow spheres towards spatial lithium deposition for stable lithium metal batteries

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Journal of Energy Chemistry 2024年第10期97卷 55-67,I0002页

作者： Jianxing Wang Shuhao Yao Runming Tao xiaolang Liu Jiazhi Geng Chang hong Huiying Li Guiyun Yu Haifeng Li xiao-Guang Sun Jianlin Li Jiyuan liang School of Optoelectronic Materials&Technology jianghan UniversityWuhan 430056HubeiChina Institute for Advanced Materials and Manufacturing University of TennesseeKnoxilTN 37996USA School of Chemistry&Chemical Engineering Yancheng Institute of TechnologyYancheng 224051JiangsuChina Chemical Sciences Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Applied Materials Division Argonne National LaboratoryLemontIL 60439USA

Lithium metal(LM)is a promising anode for next-generation batteries due to its high theoretical capacity and low electrode ***,side reactions,volume change,and unwanted lithium dendrite growth seriously limit the practical application of ***,with the aid of a hard template approach,a novel lithiophilic CoF_(2)-carbon hollow sphere(CoF_(2)@C-HS)composite material is successfully prepared via a facile in-situ fluorination and etching *** lithiophilic CoF_(2) acts as nucleation sites to reduce nucleation overpotential as well as induces the spatial Li deposition and the formation of LiFrich solid electrolyte interphase(SEI),and the hollow carbon matrix can enhance the electrical conductivity and offer free space for LM *** simulations reveal that the synergistic effect of lithiophilic CoF_(2) and hollow carbon matrix homogenizes the electric field distribution and Li~+*** from these advantages,the CoF_(2)@C-HS-modified copper substrate electrode delivers an enhanced Coulombic efficiency(CE)of 93.7%for 280 cycles at 1 mA cm^(-2)and 1 mA h cm^(-2).The symmetrical cell using CoF_(2)@C-HS can stably cycle more than 1800 h with a low voltage hysteresis of 11 mV at a current density of 0.5 MA cm^(-2)and an areal capacity of 0.5 mA h cm^(-2).Moreover,the Li@CoF_(2)@C-HS composite anode enables more than 300 stable cycles at 1 C with a capacity retention of 95%in LiFePO_(4)-based full cell and 110 stable cycles at 1 C in LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)-based highvoltage full *** work might shed a new light on designing lithiophilic hosts to spatially confine LM deposition,realizing dendrite-free LM anodes and the practical applications of LM batteries.

关键词： Lithium metal anode Spatial deposition Stability Nanocomposite Lithiophilic CoF_(2)

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Principal Model Analysis Based on Bagging PLS and PCA and Its Application in Financial Statement Fraud

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Journal of Systems Science and Information 2024年第2期12卷 212-228页

作者： xiao liang Qiwei XIE Chunyan LUO liang TANG Yi SUN School of Economics and Management Beijing University of TechnologyBeijing 100124China Shanghai Tongtu Semiconductor Technology Co. LtdShanghai 210203China School of Finance Anhui University of Finance&EconomicsBengbu 233000China

Motivated by the Bagging Partial Least Squares(Bagging PLS)and Principal Component Analysis(PCA)algorithms,a novel approach known as Principal Model Analysis(PMA)method is introduced in this *** the proposed PMA algorithm,the PCA and the Bagging PLS are *** this method,multiple PLS models are trained on sub-training sets,derived from the training set using the random sampling with replacement *** regression coefficients of all the sub-PLS models are fused in a joint regression coefficient *** final projection direction is then estimated by performing the PCA on the joint regression coefficient ***,the proposed PMA method is compared with other traditional dimension reduction methods,such as PLS,Bagging PLS,Linear discriminant analysis(LDA)and *** results on six public datasets demonstrate that our proposed method consistently outperforms other approaches in terms of classification performance and exhibits greater ***,it is employed in the application of financial statement fraud *** and other five algorithms are utilized to financial statement fraud which concerned by the academic community,and the results indicate that the classification of PMA surpassed that of the other methods.

关键词： principal model analysis partial least squares principal component analysis dimension reduction ensemble learning financial statement fraud detection

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GPa-level pressure-induced enhanced corrosion resistance in TiZrTaNbSn biomedical high-entropy alloy

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China Foundry 2024年第3期21卷 265-275页

作者： xiao-hong Wang Yu-lei Deng Qiao-yu Li Zhi-xin Xu Teng-fei Ma Xing Yang Duo Dong Dong-dong Zhu xiao-hong Yang Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou UniversityQuzhou 324000ZhejiangChina School of Materials Science and Engineering Taizhou UniversityTaizhou 318000ZhejiangChina

TiZrTaNb-based high-entropy alloys(HEAs)are research frontier of biomedical materials due to their high hardness,good yield strength,excellent wear resistance and corrosion ***,as an essential trace element in the human body that plays a significant role in physiological *** has stable chemical properties and a low elastic *** this study,a new material,TiZrTaNbSn HEAs,was proposed as a potential biomedical *** Ti_(35)Zr_(25)Ta_(15)Nb_(15)Sn_(10)biomedical high-entropy alloys(BHEAs)were successfully prepared through an arc melting furnace and then remelted using a German high-temperature and high-pressure apparatus under GPa-level(4 GPa and 7 GPa).The precipitation behavior of the needle-like HCP-Zr_(5)Sn_(3)phase that precipitates discontinuously at the grain boundary was successfully *** phase constitution,microstructure,and corrosion resistance of the alloy were *** results show that the needle-like HCP-Zr_(5)Sn_(3)phase is eliminated and the(Zr,Sn)-rich nano-precipitated phase is precipitated in the microstructure under high pressure,which leads to the narrowing of grain boundaries and consequently improves the corrosion resistance of the *** addition,the formation mechanisms of(Zr,Sn)-rich nanoprecipitates in BHEAs were *** Zr and Sn dissolve in the matrix due to the effect of high pressure,during the cooling process,they precipitate to form a(Zr,Sn)-rich nano-precipitated phase.

关键词： biomedical HEAs precipitation grain boundary corrosion resistance TiZrTaNbSn

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环圈光纤的失效预测

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光子学报 2013年第4期42卷 427-431页

作者：梁小红刘军号中国电子科技集团公司第四十六研究所天津300220

以光纤的机械可靠性为主线综述了光纤材料中固有裂纹的生长和传播所导致的光纤断裂机制.在该断裂力学的基础上推导了传统通信光纤在平直应用中的寿命预测模型.继而分析了处于弯曲构型中的传感环圈光纤表面的应力分布,然后在与传统理论... 详细信息

以光纤的机械可靠性为主线综述了光纤材料中固有裂纹的生长和传播所导致的光纤断裂机制.在该断裂力学的基础上推导了传统通信光纤在平直应用中的寿命预测模型.继而分析了处于弯曲构型中的传感环圈光纤表面的应力分布,然后在与传统理论相同的基本断裂机理下,类比于通信光纤可靠性模型的推导,据此应力分析给出了评估这种环圈光纤的机械可靠性的一般模型.进而从工程应用的角度简化了所推导出的一般模型,使之能够快速简单地给出环圈光纤失效概率的保守评估.在此简化模型的基础上,数值计算了目前常见的几种传感环圈中的光纤在服役期间的累积失效概率;其结果同时也显示了该环圈光纤的失效概率对光纤参量、环圈参量以及工艺参量的依赖关系.根据这一依赖关系,不仅可以快速评估在各种服役应力条件下具有不同寿命要求的光纤环圈的失效概率,同时也能对这些环圈的设计提供参考.

关键词：光纤失效概率机械可靠性

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Effect of infarct location and volume on cognitive dysfunction in elderly patients with acute insular cerebral infarction

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World Journal of Psychiatry 2024年第8期14卷 1190-1198页

作者： Fei-Fei liang xiao-Xia Liu Jiang-hong Liu Yang Gao Jian-Guo Dai Zi-Hui Sun Department of Geriatrics Zhangjiakou First Hospital in Hebei ProvinceZhangjiakou 075000Hebei ProvinceChina The Fourth Ward Zhangjiakou Infectious Disease HospitalZhangjiakou 075000Hebei ProvinceChina Department of Hepatobiliary and Pancreatic Surgery Zhangjiakou First Hospital in Hebei ProvinceZhangjiakou 075000Hebei ProvinceChina Department of General Medicine Zhangjiakou First Hospital in Hebei ProvinceZhangjiakou 075000Hebei ProvinceChina

BACKGROUND The aging of the population has become increasingly obvious in recent years,and the incidence of cerebral infarction has shown an increasing trend annually,with high death and disability *** To analyze the effects of infarct location and volume on cognitive dysfunction in elderly patients with acute insular cerebral *** Between January 2020 and December 2023,we treated 98 cases of elderly acute insula,patients with cerebral infarction in the cerebral infarction acute phase(3-4 weeks)and for the course of 6 months in Montreal Cognitive Assessment Scale(MoCA)for screening of ***,58 and 40 patients were placed in the cognitive impairment group and without-cognitive impairment group,*** patients with cerebral infarction,magnetic resonance imaging was used to screen and clearly analyze the MoCA scores of two groups of patients with different infarctions,the relationship between the parts of the infarction volume,and analysis of acute insula cognitive disorder in elderly patients with cerebral RESULTS The number of patients with cognitive impairment in the basal ganglia and thalamus was significantly higher than that without cognitive impairment(P<0.05).The total infarct volume in the cognitive impairment group was higher than that in the non-cognitive impairment group,and the difference was statistically significant(P<0.05).The infarct volumes at different sites in the cognitive impairment group was higher than in the non-cognitive impairment group(P<0.05).In the cognitive impairment group,the infarct volumes in the basal ganglia,thalamus,and mixed lesions were negatively correlated with the total MoCA score,with correlation coefficients of-0.67,-0.73,and-0.77,*** In elderly patients with acute insular infarction,infarction in the basal ganglia,thalamus,and mixed lesions were more likely to lead to cognitive dysfunction than in other areas,and patients with large infarct volumes were more like

关键词： Elderly Acute insular infarction Infarction site Cognitive impairment Infarction volume

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The Distribution of Surnames in Xiantao City through Isonymy

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Journal of Geodesy and Geoinformation Science 2024年第2期7卷 52-65页

作者： ZHANG Jingjing ZHU Yan xiao hong College of Chinese Language and Literature Wuhan UniversityWuhan 430072China College of Literature and Communication China Three Gorges UniversityYichang 443002China School of Foreign Languages China University of GeosciencesWuhan 430072China

The population migration in Hubei Province was frequent in history,accompanied by the migration of surnames,so it is important to study their population *** take Xiantao City as an example to explore the isonymic structure of small and medium-sized cities in *** surname distributions of 223327 residents registered in 2013 were analyzed in 5 towns and 105 villages of *** number of different surnames found was *** for surnames,theα-value reflects the influence of ethnic composition on the abundance of *** correlation between the isonymic distance and the geographic distance between villages was calculated and indicated that Euclidean distance was weakly correlated with the geographic distance(r=0.177±0.012),and the isonymic distance increased with the geographical ***,the dendrogram and PCA built from the matrix of Euclidean distances between villages identified a main surname differentiation between the urban and rural areas.

关键词： Xiantao City surname distribution isonymy isolation by distance urban and rural areas

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Hydromassage of macular hole edges for large and persistent full-thickness macular holes

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 551-557页

作者： Yi Cai Wen-Bo Liu Duo Wei Xun Deng xiao-Xin Li Ming-Wei Zhao Xuan Shi Jian-hong liang Department of Ophthalmology Peking University People’s HospitalBeijing 100044China Eye Diseases and Optometry Institute Beijing 100044China Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases Beijing 100044China College of Optometry Peking University Health Science CenterBeijing 100044China Xiamen Eye Center of Xiamen University Xiamen 361102Fujian ProvinceChina Department of Ophthalmology the Second Hospital of Lanzhou UniversityLanzhou 730030Gansu ProvinceChina

●AIM:To introduce the macular hole(MH)hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH.●METHODS:This retrospective observational case series comprised 16 consecutive patients(17 eyes)diagnosed with *** criteria involved a hole aperture diameter larger than 600μm or the presence of an unclosed MH larger than 600μm following the previous *** MH repair procedures were administered in all cases,involving the manipulation and aspiration of the hole margin through the application of water flow with a soft-tip flute needle.A comprehensive assessment was conducted for each case before and after surgery,and optical coherence tomography(OCT)images were captured at every follow-up point.●RESULTS:The mean preoperative aperture diameter was 747±156μm(range 611-1180μm),with a mean base diameter of 1390±435μm(range 578-2220μm).Following surgery,all cases achieved complete anatomical closure of MH,with 13 cases(76.5%)exhibiting type 1 closure and 4 cases(23.5%)demonstrating type 2 *** significant differences were observed in the preoperative OCT variables between the two closure *** with type 1 closure showed a significantly improved visual acuity(0.70±0.10,range 0.50-0.80)compared to those with type 2 closure(0.90±0.12,range 0.80-1.00,P=0.014).●CONCLUSION:The MH hydromassage technique demonstrates promising results,achieving acceptable closure rates in cases of large or persistent *** technique may serve as an effective adjunctive maneuver during challenging MH surgery.

关键词： macular hole large macular hole persistent macular hole optical coherence tomography surgical technique hydromassage

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Deuterium distribution and behavior of blisters in pre-damaged and undamaged tungsten

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Tungsten 2024年第3期6卷 647-656页

作者： Cong Li xiao-Wa Wang Ran-Ran Su Xuan-Xin Hu Shu-Guang Wei Han-Jun Tu Li-Qun Shi hong-liang Zhang Key Laboratory of Nuclear Physics and Ion-Beam Application Institute of Modern Physics Fudan University School of Mechanical Engineering Shanghai Jiao Tong University Department of Materials Science and Engineering University of Wisconsin

Tungsten(W),as a plasma-facing material,is subjected to high fluence plasma,resulting in both radiation damage and deuterium(D) *** study explores the blistering behavior and D supersaturated layers in both pre-damaged and undamaged W *** achieve a uniform damage profile similar to neutron irradiation,carbon(C) ions with multiple energies and angles were *** samples were further irradiated with low-energy D ions under two fluences at temperatures from ～380 to 640 *** various experimental techniques,we found that pre-damaged W samples can effectively suppress the formation of blistering and lower the threshold temperature at which the surface remains free of *** also observed the prominent D supersaturated peaks within the depth of 20 nm in both pre-damaged and undamaged ***,a close correlation between blistering and the D supersaturation was *** results suggest that neutron irradiation in the fusion reactors could increase the critical D concentration for blistering,while a greater depth of damage facilitated the inward diffusion of D,thereby reducing the D concentration gradient and alleviating surface blistering.

关键词： Tungsten Deuterium Supersaturated layer Blister Ion irradiation Pre-damage

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