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Journal of Ocean University of China 2024年第4期23卷 1067-1075页

作者： LIAN Chunyu LI Ping ZHANG Tengteng SHAO Chen Department of Zoology College of Life SciencesShaanxi Normal UniversityXi’an 710119China Powerchina northwest Engineering corporation Limited Xi’an 710065China

Hypotrichs are one of the highly differentiated ciliated lineages which play important roles in ecological, environmental,evolutionary and basic biological studies. In the present study, we investigated the living characteristics, infraciliature, nuclear apparatus, ontogenesis and phylogenetic position of a marine hypotrichous ciliate, Apokeronopsis wrighti Long et al., 2008, which was isolated from coastal waters in Shenzhen, China. The new isolate resembles the type population in terms of morphological characteristics, morphometrics, and SSU rRNA gene sequence that is with a 99.7% similarity. Ontogenesis of A. wrighti is characterized by oral primordium for the proter as well as marginal and dorsal kineties anlagen in both filial products formed de novo, and the cirral row arranged along the paroral and endoral arises from several anterior frontoventral-transverse cirral streaks. Phylogenetic analyses based on SSU and concatenated gene data suggest that five species of Apokeronopsis form a monophyletic clade, and the genus Apokeronopsis is closely related to Thigmokeronopsis and Metaurostylopsis.

关键词： 18S rRNA gene Apokeronopsis ciliated protists multi-gene ontogenesis systematics Urostylida

A Novel Fracturing Fluid with High-Temperature Resistance for Ultra-Deep Reservoirs

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Fluid Dynamics & Materials Processing 2024年第5期20卷 975-987页

作者： Lian Liu Liang Li Kebo Jiao Junwei Fang Yun Luo northwest Oilfield Branch China Petroleum&Chemical CorporationUrumqi830011China Sinopec Key Laboratory for Enhanced Recovery in Fractured and Cavernous Reservoir Urumqi830011China

Ultra-deep reservoirs play an important role at present in fossil energy *** to the related high temperature,high pressure,and high formation fracture pressure,however,methods for oil well stimulation do not produce satisfactory results when conventional fracturing fluids with a low pumping rate are *** response to the above problem,a fracturing fluid with a density of 1.2~1.4 g/cm^(3)was developed by using Potassium formatted,hydroxypropyl guanidine gum and zirconium crosslinking *** fracturing fluid was tested and its ability to maintain a viscosity of 100 mPa.s over more than 60 min was verified under a shear rate of 1701/s and at a temperature of 175℃.This fluid has good sand-carrying performances,a low viscosity after breaking the rubber,and the residue content is less than 200 mg/*** with ordinary reconstruction fluid,it can increase the density by 30%~40%and reduce the wellhead pressure of 8000 m level reconstruction ***,the new fracturing fluid can significantly mitigate safety risks.

关键词： Ultra-deep reservoir high-temperature resistance weighted fracturing fluid guanidine gum potassium formatted

A unique role of the pyrimidine de novo synthesis enzyme ODCase in Lysobacter enzymogenes

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Journal of Integrative Agriculture 2024年第9期 3066-3077页

作者： Mingming Yang Yunxiao Tan Jiabing Ma Yingjia Zhao Xia Yan Nana Wang Pingping Wang Jiaqi Tan Suilong Ai Xiaofei Liang Bangshuai Chang Obadah E.A.Yousif Chao Zhao Bo Wang Guoliang Qian Lili Huang State Key Laboratory for Crop Stress Resistance and High-Efficiency Production Northwest A&F University CChoillneage of Plant Protection Northwest A&F University College of Life Sciences Northwest A&F University College of Natural Resources and Environment Northwest A&F University Shaanxi Provincial Tobacco corporation of China National Tobacco corporation Institute of Plant Protection Jiangsu Academy of Agricultural Sciences College of Plant Protection Laboratory of Plant ImmunityNanjing Agricultural University

Bacterial species of the genus Lysobacter are environmentally ubiquitous with strong antifungal biocontrol ***-stable antifungal factor （HSAF） secreted by the biocontrol bacterium Lysobacter enzymogenes OH11 has broad-spectrum and highly efficient antifungal *** the biosynthetic regulations of HSAF would lay an important foundation for strain engineering toward improved HSAF *** this work,we demonstrate that Le0752,an orotidine-5′-phosphate decarboxylase enzyme （ODCase） catalyzing a pivotal step of the UMP de novo biosynthesis pathway,is vital for HSAF-mediated antimicrobial activities and growth of *** OH11,but not for twitching *** gene regulates the production of HSAF by affecting the expression of lafB,a key gene in the HSAF biosynthesis operon,through the transcription factor ***,bioinformatics analysis revealed that Le0752 belongs to the Group III ODCases,whereas its homologs in the closely related genera Xanthomonas and Stenotrophomonas belong to Group I,which contains most ODCases from Gram-positive bacteria,Gramnegative bacteria and ***,the Group I ODCase PXO＿3614 from the Xanthomonas oryzae *** PXO99Astrain complemented the Le0752 mutant in regulating HSAF-mediated antagonistic ***,these results highlight the important requirement of de novo pyrimidine biosynthetic enzymes for antibiotic HSAF production in ***,which lays an important foundation for improving HSAF production via metabolic flow design and for dissecting the regulatory functions of bacterial ODCases

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Large-scale toppling slope under water level fluctuation of reservoir:A case of Yunnan Province,China

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3034-3046页

作者： Leilei Jin Yufeng Wei Fei Ye Wenxi Fu Jianfeng Liu Shuwu Li State Key Laboratory of Hydraulic and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China northwest Engineering corporation Limited Xi’an710065China

Landslides induced by reservoir inundation are common in Southwest China,negatively influencing hydropower *** hydropower station dam was constructed in the upper reaches of the Lancang River,accordingly causing the water level at the Lajinshengu slope to increase by 30 m.A tension crack with a visible depth of 8 m was observed in the upper sector of the Lajinshengu slope after reservoir impoundment for 170 *** the following days,numerous cracks appeared on the surface of the slope,and the maximum displacement of the slope reached 3.22 ***,a large-scale active deformation body within the Lajinshengu slope formed with an area of 2.62×10^(5)m^(2)and a volume of 1.65×10^(7)m^(3).Detailed field investigations,on-site monitoring,and centrifugal model tests were carried out to analyze the surface features,deformation characteristics,and failure mechanism of the Lajinshengu *** results show that the slope is an ancient landslide,divided into two parts(*** A and zone B)by the *** B is a traction landslide caused by the displacement of zone *** longterm inundation weakens the soft rock at the slope foot,intensifying the toppling of bedrock and consequently triggering the sliding of the overburden in zone *** failure mode of the Lajinshengu slope is a typical case of toppling-sliding failure,and the underlying rock toppling drives the overlying *** addition,early identification methods for toppling deformation covered by overburdened soil were proposed based on monitoring data and deformation signs.

关键词： Lajinshengu slope Reservoir impoundment Early identification Failure mechanism Toppling-sliding slope failure mode

Change of pore water near the freezing front during soil freezing: Migration and mechanisms

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Pedosphere 2024年第4期34卷 770-782页

作者： Yajun SHI Wei MA Lianhai ZHANG Chengsong YANG Fei SHANG Cheng CHEN State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Joint NMR Laboratory for Freeze-Thaw Processes in Soils of State Key Laboratory of Frozen Soil Engineering and Suzhou Niumag Analytical Instrument corporation

The formation and growth of segregation ice dominate the frost heave during soil freezing, which is closely related to water migration. To analyze segregation ice during soil freezing for different soils, a freezing-thawing experiment was conducted with Lanzhou loess(LZL) and Qinghai-Tibet Plateau silty clay(QSC) using a novel layered nuclear magnetic resonance approach. During LZL freezing, the unfrozen water content first increased and then decreased with decreasing temperature near the freezing front, but decreased with decreasing temperature in other layers, whereas during the freezing of QSC, the unfrozen water content in different layers(including the freezing front) decreased with decreased temperature. Notably, the increased liquid water near the freezing front during LZL freezing was primarily adsorbed water. In addition to the temperature gradient, the squeezing action during soil freezing was another important factor affecting water migration, especially at the early stage of soil freezing. However, which of the two factors, squeezing action and temperature gradient, was the dominant one causing water migration depended on soil structure. At the early stage of soil freezing, the squeezing action had a significant effect on the water migration of LZL, but no significant effect on that of QSC. Furthermore, water accumulation of LZL near the freezing front due to squeezing action at the early stage of freezing limited the formation and growth of segregation ice. This study provided an improved understanding for ice segregation and water migration during soil freezing.

关键词： frozen soil nuclear magnetic resonance segregation ice unfrozen water water migration

The Middle and Lower Cambrian salt tectonics in the central Tarim Basin,China:A case study based on strike-slip fault characterization

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Energy Geoscience 2024年第2期5卷 53-61页

作者： Qing Bian Jibiao Zhang Cheng Huang SINOPEC Petroleum Exploration and Production Research Institute BeijingChina SINOPEC northwest Oilfield Company UrumuqiChina

Due to the considerable depth of the salt layers and the lack of calibration by exploratory drilling,the interpretation of the Middle and Lower Cambrian salt formations in the central Tarim Basin poses a *** this paper,we apply the coupling and decoupling deformation theory in salt tectonics to analyze the No.7 fault mapped in the seismic datasets by the response characteristics of the Middle and Lower Cambrian *** quantifying the stratigraphic framework of the Middle and Lower Cambrian strata,we define the position of the salt layer with the seismic *** decoupling is observed in the Middle and Lower Cambrian sequences in the Shuntuoguole Low Uplift,while deformation coupling is observed in these two sequences in the Shaya Uplift.

关键词： Tarim Basin Salt tectonics Strike-slip fault Structural analysis Seismic interpretation of decoupling zone

A Scenario-classification Hybrid-based Banding Method for Power Transfer Limits of Critical Inter-corridors

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 547-560页

作者： Lidong Yi Maosheng Ding Jili Wang Gao Qiu Fei Xue Ji'ang Liu Yuxiong Huang Gengfeng Li Junyong Liu State Grid Ningxia Electric Power Co. Ltd.YinchuanChinaand M.Ding is also with State Grid Ningxia Electric Power Research InstituteYinchuanChina northwest Branch State Grid Corporation of ChinaXi’anChina School of Electrical Engineering Sichuan UniversityChengduChina State Grid Ningxia Electric Power Research Institute Yinchuan YinchuanChina School of Electrical Engineering Xi’an Jiaotong UniversityXi’anChina IEEE

To secure power system operations,practical dispatches in industries place a steady power transfer limit on critical inter-corridors,rather than high-dimensional and strong nonlinear stability ***,computational complexities lead to over-conservative pre-settings of transfer limit,which further induce undesirable and non-technical congestion of power *** conquer this barrier,a scenario-classification hybrid-based banding method is proposed.A cluster technique is adopted to separate similarities from historical and generated operating condition *** a practical rule,transfer limits are approximated for each operating ***,toward an interpretable online transfer limit decision,costsensitive learning is applied to identify cluster affiliation to assign a transfer limit for a given *** this stage,critical variables that affect the transfer limit are also picked out via mean impact *** enables us to construct low-complexity and dispatcher-friendly rules for fast determination of transfer *** numerical case studies on the IEEE 39-bus system and a real-world regional power system in China illustrate the effectiveness and conservativeness of the proposed method.

关键词： Transfer limit transfer capability power transfer inter-corridor cluster cost-sensitive learning banding power system operation

Application of a concrete thermal pile in cooling the warming permafrost under climate change

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Advances in Climate Change Research 2024年第1期15卷 170-183页

作者： Yun-Hu SHANG Fu-Jun NIU Guo-Yu LI Jian-Hong FANG Ze-Yong GAO State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Da Xing'anling Observation and Research Station of Frozen-Ground Engineering and Environment Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesJagdaqi 165000China Qinghai Research Institute of Transportation Xining 810008China

Permafrost degradation caused by climate warming is posing a serious threat to the stability of cast-in-place pile foundations in warm permafrost *** cold energy can be effectively utilized by two-phase closed thermosyphons(TPCTs)to cool the ***,we installed TPCTs in a cast-in-place pile foundation to create a unique structure called a thermal pile,which effectively utilizes the TPCTs to regulate ground *** we conducted a case study and numerical simulation to exhibit the cooling performance,and optimize the structure of the thermal *** purpose of this study is to promote the application of thermal piles in unstable permafrost *** on the findings,the thermal pile operated for approximately 53%of the entire year and effectively reduced the deep ground temperature at a rate of at least-0.1℃per ***,it successfully raised the permafrost table that is 0.35 m shallower than the natural ground *** characteristics prove highly beneficial in mitigating the adverse effects of permafrost degradation and enhancing infrastructure *** the length of the condenser section and the diameter of the TPCT in a suitable manner can effectively enhance the cooling capability of the thermal pile and ensure the long-term mechanical stability of the pile foundation even under climate warming.

关键词： Heat transfer Cold energy Warm permafrost Two-phase closed thermosyphons Cast-in-place pile foundation

Thermal performance of cast-in-place piles with artificial ground freezing in permafrost regions

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Journal of Mountain Science 2024年第4期21卷 1307-1328页

作者： WANG Xinbin CHEN Kun YU Qihao GUO Lei YOU Yanhui JIN Mingyang State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

During the construction of cast-in-place piles in warm permafrost,the heat carried by concrete and the cement hydration reaction can cause strong thermal disturbance to the surrounding *** the bearing capacity of the pile is quite small before the full freeze-back,the quick refreezing of the native soils surrounding the cast-in-place pile has become the focus of the infrastructure construction in *** solve this problem,this paper innovatively puts forward the application of the artificial ground freezing(AGF)method at the end of the curing period of cast-in-place piles in permafrost.A field test on the AGF was conducted at the Beiluhe Observation and Research Station of Frozen Soil Engineering and Environment(34°51.2'N,92°56.4'E)in the Qinghai Tibet Plateau(QTP),and then a 3-D numerical model was established to investigate the thermal performance of piles using AGF under different engineering ***,the long-term thermal performance of piles after the completion of AGF under different conditions was *** experiment results demonstrate that AGF is an effective method to reduce the refreezing time of the soil surrounding the piles constructed in permafrost terrain,with the ability to reduce the pile-soil interface temperatures to below the natural ground temperature within 3 *** results further prove that AGF still has a good cooling effect even under unfavorable engineering conditions such as high pouring temperature,large pile diameter,and large pile ***,the application of this method is meaningful to save the subsequent latency time and solve the problem of thermal disturbance in pile construction in *** research results are highly relevant for the spread of AGF technology and the rapid building of pile foundations in permafrost.

关键词： Permafrost engineering Cast-in-place pile Artificial ground freezing Thermal performance.

Building a More Sustainable Chinese Loess Plateau

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Journal of Earth Science 2024年第1期35卷 283-287页

作者： Peiyue Li Xiaomei Kou Yong Wang Le Niu School of Water and Environment Chang'an UniversityXi'an 710054China Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education Chang'an UniversityXi'an 710054China Key Laboratory of Eco-Hydrology and Water Security in Arid and Semi-Arid Regions of the Ministry of Water Resources Chang'an UniversityXi'an 710054China PowerChina northwest Engineering corporation Limited Xi'an 710065China PowerChina Sinohydro Bureau 3 Co. LTD.Xi'an 710024China

The Chinese Loess Plateau,a region of remarkable ecological and economic value,grapples with significant water management challenges due to its distinctive geology and *** perspective offers a short review of the eco-environmental protection measures undertaken in the Loess Plateau,underscoring the transformative impacts of initiatives such as the“Grain for Green”***,it also highlights the enduring challenges,including land degradation,water resources issues,socio-economic inequities,and the implications of climate ***,water management emerges as a pivotal issue with far-reaching repercussions for soil conservation,biodiversity,and human *** paper concludes by proposing future actions,emphasizing the necessity for policy modifications,novel initiatives,and research to tackle these challenges and foster sustainable development in the Loess *** insights gained from this region could offer invaluable lessons for other regions confronted with similar challenges,thereby contributing to global efforts to mitigate desertification and champion sustainable development.

关键词： Loess Plateau eco-environmental protection water management sustainable development climate change