检索结果-南通市图书馆

TRANSMISSION BEHAVIOR OF MUD-PRESSURE PULSE ALONG WELL boRE

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2007年第2期19卷 236-240页

作者： LIU Xiu-shan LI bo yue Yu-quan Petroleum Drilling Research Institute Exploration and Production Research Institute of Sinopec Corp. Dezhou 253005 China Technical Department Tianjin Branch of CNOOC Ltd. Tianjin 300452 China Jinzhou Oil Production Plant Liaohe Oilfield Branch of PetroChina Linghai 121209 China

In oil and gas industry, mud-pulse telemetry has been widely used to obtain directional data, drilling parameters, formation evaluation data and safety data, etc. Generally, the drilling mud in most current models was considered to be a single-phase fluid through which the mud pulses travel, despite the fact that the drilling mud is composed of two or more phases. In this article, a multiphase flow formula was proposed to calculate the mud-pulse velocity as mud solids and free-gas content change, and a mathematical model was put forward to simulate the dynamic-transmission behavior of the mud-pressure pulse or waves. Compared to conventional methods, the present model provides more accurate mud-pulse attenuation, and the dynamic-transmission behavior of drilling-mud pulses along well bores can also be easily examined. The model is valuable in improving the existing mud-pulse systems and developing new drilling-mud pulse systems.

关键词： measurement-while-drilling (MWD),closed-loop drilling multiphase flow numerical simulation

Review on the Characteristics,Heating Sources and Evolutionary Processes of the Operating Composite Insulators with Abnormal Temperature Rise

在线全文

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2022年第3期8卷 910-921页

作者： Zhikang Yuan Youping Tu Ruihai Li Fuzeng Zhang bo Gong cong Wang State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing102206China Electric Power Research Institute China Southern Power Grid Co.Ltd.Guangzhou510080China

This paper reviews the research progress on abnormal temperature rise(ATR)of composite *** ATR of composite insulators can be divided into two types,point-form temperature rise(PFTR)and bar-form temperature rise(BFTR).The composite insulators with PFTR only show significant temperature rise at high relative humidity(RH)(>70%),and the temperature rise is located in the area that is 20 cm above the metal *** a low humidity environment(both high(>70%)and low(both conductance loss and polarization loss of the corroded GRP *** decay-like degradation of the GRP core is caused by the combination of damp conditions,high electric field,discharge,mechanical load,et *** may evolve into a decay-like fracture of the composite *** preventive methods concerning quality control,structure optimization,material modification and operational strategy are *** is suggested that when PFTR is detected on the composite insulator,the inspection period of the insulator should be properly *** composite insulator should be replaced as soon as the BFTR was detected.

关键词： Abnormal temperature rise composite insulator glass fiber reinforced plastic(GRP)core silicone rubber housing

Rapid,specific and sensitive detection of Vibrio vulnificus by loop-mediated isothermal amplification targeted to vvhA gene

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2018年第4期37卷 83-88页

作者： ZHANG Lina WANG Mingyi cong Dianxia DING Shuyan cong Rinan yue Jinyong GENG Jianli HU Chengjin Department of Laboratory Medicine General Hospital of Jinan Military Region of PLA Department of Central Laboratory Weihai Municipal Hospital affiliated to Dalian Medical University

Vibrio vulnificus is an estuarine bacterial pathogen for *** rapid,specific and sensitive detection of *** is urgently needed for early disease diagnosis and timely treatment of *** *** the study,a loop-mediated isothermal amplification（LAMP） technique was developed for *** detection with a set of primers,composed of two out primers and two inner primers targeted to vvh A *** optimal amplification temperature was 63°C and the reaction only took 35 *** amplification products could not only be detected by agarose gel electrophoresis with ladder-like pattern bands,but also could be visualized using calcein with naked eye ***-five strains were tested for the specificity of LAMP assay,and all the *** strains were identified correctly while other strains were negative *** sensitive of the new LAMP assay was 100-fold more sensitive than the conventional ***,all the *** strains were detected correctly in spiked,clinical and environmental samples by the new LAMP *** with other well-known techniques,the new LAMP assay targeted to vvh A gene was extremely rapid,simple,sensitive and specific for *** identification.

关键词： Vibrio uulnificus loop-mediated isothermal amplification vvhA gene

Siphon-Specific Expression of an Actin Encoding Gene Is Regulated by Six1/2 in Ciona savignyi

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2022年第6期21卷 1597-1606页

作者： yue Wenxuan QIAO Jinghan YANG Xiuxia DONG bo Sars-Fang Center MOE Key Laboratory of Marine Genetics and BreedingCollege of Marine Life SciencesOcean University of ChinaQingdao 266003China Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Institute of Evolution and Marine Biodiversity Ocean University of ChinaQingdao 266003China

Actin is a ubiquitous protein and plays essential roles on cellular structure maintenance and cellular motility in both muscle and non-muscle *** genes encoding muscle actin have been identified from the ascidians,including those expressed in the larval tail muscle,the adult body-wall muscle,and adult heart *** this study,a novel striated non-tail muscle actin gene was identified from the RNA-seq data of Ciona savignyi *** analysis,alignment of the N-terminal amino acid sequences and comparation of diagnostic residues provided evidence that it had high similarity with vertebrate cardiac and skeletal muscle *** situ hybridization and promoter-driven GFP reporter assay revealed that it was specifically expressed in the primordia of the oral and atrial *** hereby defined it as siphon-specific muscle actin coding gene(Cs-SMA).A 201 bp(−1350 bp to−1150 bp)sequence containing T-box and Six1/2 binding motif within the upstream region of Cs-SMA confined the expression of GFP in the siphons of electroporated ***1/2 binding motif was experimentally confirmed to play indispensable role in controlling the siphon-specific expression of *** tissue-specific expression of Cs-SMA in the siphon primordia indicated its potential crucial roles in Ciona embryogenesis and organogenesis.

关键词： Ciona savignyi actin encoding gene siphon Six1/2 expression regulation

Future prospect of“Gut microbiome composition can predict the response to nivolumab in advanced hepatocellular carcinoma patients”

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2022年第20期28卷 2248-2250页

作者： Yong-bo Kang yue Cai Department of Microbiology and Immunology School of Basic Medical SciencesShanxi Medical UniversityJinzhong 030600Shanxi ProvinceChina

Recently,we read the article“Gut microbiome composition can predict the response to nivolumab in advanced hepatocellular carcinoma patients”with interest,and it is preliminary suggested that gut microbiota is closely related to therapeutic effect of *** on the meaningful results of this article,several valuable research directions are proposed to enhance the therapeutic effect of immune checkpoint inhibitors on advanced hepatocellular carcinoma.

关键词： Gut microbiome Immunotherapy Immune checkpoint inhibitor resistance Probiotics Faecal microbiota transplantation Hepatocellular carcinoma Prognosis

Sonar Image Target Detection for Underwater Communication System Based on Deep Neural Network

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2023年第12期137卷 2641-2659页

作者： Lilan Zou bo Liang Xu Cheng Shufa Li cong Lin College of Electronic and Information Engineering Guangdong Ocean UniversityZhanjiang524088China Smart Innovation Norway Hakon Melbergs vei 16Halden1783Norway

Target signal acquisition and detection based on sonar images is a challenging task due to the complex underwater *** order to solve the problem that some semantic information in sonar images is lost and model detection performance is degraded due to the complex imaging environment,we proposed a more effective and robust target detection framework based on deep learning,which can make full use of the acoustic shadow information in the forward-looking sonar images to assist underwater target ***,the weighted box fusion method is adopted to generate a fusion box by weighted fusion of prediction boxes with high confidence,so as to obtain accurate acoustic shadow ***,the acoustic shadow box is cut down to get the feature map containing the acoustic shadow information,and then the acoustic shadow feature map and the target information feature map are adaptively fused to make full use of the acoustic shadow feature *** addition,we introduce a threshold processing module to improve the attention of the model to important feature *** the underwater sonar dataset provided by Pengcheng Laboratory,the proposed method improved the average accuracy by 3.14%at the IoU threshold of 0.7,which is better than the current traditional target detection model.

关键词： Underwater communication intelligent sensor network target detection weighted frame fusion shadow information

Biomass chemical looping gasification for syngas production using modified hematite as oxygen carriers

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2023年第3期125卷 171-184页

作者： cong Jiang Xiaoyu Jin Tingting Xu bo Xiao Zhiquan Hu Xun Wang School of Environmental Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Coal Combustion Huazhong University of Science and TechnologyWuhan 430074China

Syngas is a clean energy carrier and a major industrial feedstock. In this paper, syngas was produced via biomass chemical looping gasification(CLG) process. Hematite, the most common Fe-based oxygen carrier(OC), was modified with different metal oxides(CeO_(2), CaO and MgO) by the impregnation method. The hematite modified by CeO_(2), CaO and MgO was namely as CeO_(2)-hematite(CeO_(2)-H), CaO-hematite(CaO-H) and MgO-hematite(MgO-H), respectively. The introduction of CeO_(2), CaO and MgO enhanced the reactivity of lattice oxygen of hematite. The optimum condition for syngas production had been explored as the mass ratio of oxygen carrier to biomass(O/B) of 0.2, the mass ratio of steam to biomass(S/B) of0.75 and temperature of 800℃in the biomass CLG process. The CeO_(2)-H exhibited the most wonderful performance compared to that for CaO-H and MgO-H. The crystal composition of OC influenced greatly in the CLG process. CeFeO_(3)had a good oxygen mobility property and lattice oxygen releasing capacity due to the most oxygen vacancy distributed on the OC surface and the most active lattice oxygen, which is conducive to the biomass chemical looping gasification process for syngas production, leading to the highest gasification efficiency of 95.86% and gas yield of 1.20 m^(3)/kg of the three. Cyclic test proved that CeO_(2)-H had well sintering resistance and cyclic performance.

关键词： Chemical looping gasification Oxygen carrier Syngas Modified hematite Pine sawdust

Impact of Plant Density on the Formation of Potato Mimitubers Derived from Microtubers and Tip-Cuttings in Plastic Houses

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2013年第6期12卷 1008-1017页

作者： JIN Hui LIU Jun SONG bo-tao XIE cong-hua Key Laboratory of Horticultural Plant Biology Ministry of Education/Potato Engineering Research Center of Hubei Province Huazhong Agricultural University

The potato minitubers have been widely used for the elite seed propagation to improve the seed potato system in China. However, little information is available for an efficient production of the minitubers with high plant density in the protected growing conditions like plastic houses. In present research, the minitubers of a wide-grown potato variety, Favorita, were produced with the microtubers from tissue culture and the tip-cuttings of the microtuber plants. Three plant densities, 200, 400 and 600 microtubers or plants m-2 were set up with the randomized block design of 3 replications and the experiment was repeated in 4 seasons in 2009-2010. The canopy development, light interception, dry weight production and partitioning, tuberization and tuber weight were investigated to elucidate the mechanism by which the plant density affects the formation and growth of the minitubers. The results showed that the number of the tubers formed per unite area was in line with the increase in plant density. The difference in leaf area index （LAI） between the plant densities, especially in early stage of the plant growth, resulted in more radiation interception and dry weight producing in higher plant density than in lower one. However, our analysis demonstrated that the conversion coefficient of the cumulative intercepted radiation to plant weight and the dry weight partition rate to the tubers were constant between plant densities, suggesting that less amount of the photoassimilates partitioned to individual tubers is causal for more small tubers in high plant density. A negative exponential curve model, determined by total number of tubers produced per unit area and the mean tuber weight, fitted well to the tuber size distribution pattern. The optimum plant density could be estimated from this model for a maximum production of the minitubers with desired size.

关键词： potato minituber microtuber tip-cutting plant density

Solitary necrotic nodules of the liver with"ring"-like calcification:A case report

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2022年第21期10卷 7409-7414页

作者： Jin-Peng Bao Hu Tian Hao-Chen Wang cong-cong Wang bo Li Department of General Surgery The First Affiliated Hospital of Shandong First Medical University&Shandong Provincial Qianfoshan HospitalJinan 250014Shandong ProvinceChina Department of Gastroenterology Shandong First Medical UniversityJinan 250024Shandong ProvinceChina Department of General Surgery Shandong Provincial Qianfoshan HospitalShandong UniversityJinan 250100Shandong ProvinceChina

BACKGROUND Solitary necrotic nodule of the liver(SNNL)is a rare benign lesion with a complete necrotic core and a clear fibrous capsule containing elastic *** present the case of a patient with a radiographic computed tomography(CT)finding of"ring"-like annular calcification within the lesion and postoperative pathologic diagnosis of necrotic nodules wrapped by dense fibers in liver tissue,as well as the patient's subsequent management and *** SUMMARY A 38-year-old Chinese woman with a history of systemic lupus erythematosus treated with prednisone and hydroxychloroquine,without any symptoms,was found to have hepatic space-occupying lesions by imaging examination at a health examination.A subsequent CT scan suggested a space-occupying lesion of the liver with annular calcification,which was not defined to be benign or *** that,a laparoscopic hepatic space-occupying resection was *** postoperative pathological diagnosis was necrotic nodules wrapped by dense fibers in the liver tissue,and the final diagnosis was *** patient had an uneventful postoperative *** There is a"ring"-like calcification in *** patient had a history of systemic lupus erythematosus,without a history of parasite infection,trauma,or ***,whether the etiology and pathological changes of SNNL are related to rheumatic immune diseases remains to be investigated.

关键词： Solitary necrotic nodules of the liver Annular calcification Rheumatic immune disease Laparoscopic hepatic space-occupying resection Case report