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Clinical value of oral contrast-enhanced ultrasonography in diagnosis of gastric tumors

World Journal of Gastrointestinal Oncology 2024年第1期16卷 110-117页

作者： Chuan-Yu Wang Xiao-Jing Fan Fei-Liang Wang Yue-Yue Ge Zhao cai wei Wang Xin-ping Zhou Jun Du De-wei Dai Department of Ultrasound Medicine Beijing HospitalBeijing 100005China Department of Gastroscopy Beijing HospitalBeijing 100005China Department of General Surgery Beijing HospitalBeijing 100005China Department of Pathology Beijing HospitalBeijing 100005China

BACKGROUND The incidence of gastric cancer remains high,and it is the sixth most common cancer and the fourth leading cause of cancer deaths *** contrastenhanced ultrasonography is a simple,non-invasive,and painless method for the diagnosis of gastric *** To explore the diagnostic value of oral contrast-enhanced ultrasonography for the detection of gastric *** The screening results based on oral contrast-enhanced ultrasonography and electronic gastroscopy were compared with those of the postoperative pathological *** Among 42 patients with gastric tumors enrolled in the study,the diagnostic accordance rate was 95.2%for oral contrast-enhanced ultrasonography(n=40)and 90.5%for electronic gastroscopy(n=38)compared with postoperative pathological *** Kappa value of consistency test with pathological findings was 0.812 for oral contrast-enhanced ultrasonography and 0.718 for electronic gastroscopy,and there was no significant difference between them(P=0.397).For the TNM staging of gastric tumors,the accuracy rate of oral contrast enhanced ultrasonography was 81.9%for the overall T staging and 50%,77.8%,100%,and 100%for T1,T2,T3,and T4 staging,*** sensitivity and specificity were both 100%for stages T3 and *** diagnostic accuracy rate of oral contrast-enhanced ultrasonography was 93.8%,80%,100%,and 100%for stages N0,N1-N3,M0,and M1,*** The accordance rate of qualitative diagnosis by oral contrast-enhanced ultrasonography is comparable to that of gastroscopy,and it could be used as the preferred method for the early screening of gastric tumors.

关键词： Oral contrast-enhanced ultrasonography Gastric tumor Electronic gastroscopy Controlled study Pathological examination Diagnosis

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Effect of Fluoride on the Ion-association of Calcium Phosphate and Crystallization of Hydroxyapatite

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 831-838页

作者：宋昊月 cai Meng 袁萍邹朝勇 School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and the formation of ACP nanospheres in a buffer solution with constant ionic ***,the stability of ACP increased with increasing fluoride concentration,which was ascribed to the inhibitory effect of fluoride on the aggregation of ACP nanospheres and the nucleation of nanocrystals on the surface of ACP ***,fluoride could inhibit the lateral growth of HAP nanosheets and promote the formation of rod-like *** results further improve our understanding of the crystallization pathway of HAP crystals and the regulatory effects of fluoride.

关键词： crystallization amorphous calcium phosphate hydroxyapatite fluoride

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Distinct effect of preparation methods on reaction efficiency of Mn-Ce/Al_(2)O_(3) catalysts in low-temperature NH_(3)-SCR

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Journal of Rare Earths 2024年第10期42卷 1865-1872页

作者： Shijie Hao Yandi cai wei wei Yanan Lv Jjiawei Ji wei Tan Jingfang Sun Liwei Jia Changjin Tang Lin Dong State Key Laboratory of Pollution Control and Resource Reuse School of Environmentjiangsu Key Laboratory of Vehicle Emissions ControlCenter of Modern AnalysisKey Laboratory of Mesoscopic Chemistry of MOESchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China Wuxi weifu Environmental Catalysts Co. LtdWuxi214028China School of Environment Nanjing Normal UniversityNanjing210023China

In this study,a series of Mn-Ce/Al_(2)O_(3) catalysts was prepared by different methods of depositionprecipitation(MnCeAl-DP),impregnation(MnCeAl-IM) and citric acid(MnCeAl-CA),and the distinct effect of preparation methods on NO_x removal performance at low temperature was *** show that MnCeAl-DP exhibits not only the best activity but also the highest resistance against SO_(2)/H_(2)*** the assistance of comprehensive characterizations from scanning electron microscopy(SEM),Brunauer-Emmett-Teller(BET),X-ray diffraction(XRD),H_(2)-temperature programmed reduction(H_(2)-TPR),NH_(3)-te mperature programmed deso rption(NH_(3)-TPD),and X-ray photoelectron spectroscopy(XPS),it is revealed that the MnCeAl-DP sample owns admired features of large surface area and pore volume,enriched Mn^(4+) and chemisorbed oxygen species originating from enhanced interaction between MnO_x and CeO_(2),as well as improved adsorption capacity to NH_3 and *** these factors contribute to activity *** in-situ DRIFTS studies reveal that the improvement of NH_(3)-SCR performance over MnCeAI-DP is related to the formation of abundant nitrate species,which is beneficial to the "NH_(4)NO_(3)" reaction pathway and thus enhances low-temperature activity.

关键词： Mn-Ce/Al_(2)O_(3)catalysts NH_(3)-SCR Low temperature NH_(4)NO_(3) Fast SCR Rare earths

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A comprehensive fluid-solid coupling dynamic simulation for spatiotemporal distribution of regression rate in hybrid rocket motors

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Chinese Journal of Aeronautics 2024年第9期37卷 100-112页

作者： Tianfang wei Guobiao cai Hui TIAN Xiangyu MENG Xianzhu JIANG Xiaoming GU School of Astronautics Beihang UniversityBeijing 100191China Key Laboratory of Spacecraft Design Optimization&Dynamic Simulation Technologies Ministry of Education Beijing 100191China

The spatiotemporal distribution characteristics of the regression rate are crucial aspects of the research on Hybrid Rocket Motor(HRM).This study presents a pioneering effort in achiev-ing a comprehensive numerical simulation of fluid dynamics and heat transfer in both the fluid and solid regions throughout the entire operation of an *** accomplish this,a dynamic grid tech-nique that incorporates fluid-solid coupling is *** validate the precision of the numerical simulations,a firing test is conducted,with embedded thermocouple probes being used to measure the inner temperature of the fuel *** temperature variations in the solid fuel obtained from both experiment and simulations show good *** maximum combustion temperature and average thrust obtained from the simulations are found to deviate from the experimental results by only 3.3%and 2.4%,***,it can be demonstrated that transient numerical simu-lations accurately capture the fluid-solid coupling characteristics and transient regression *** dynamic simulation results of inner flow field and solid region throughout the entire working stage reveal that the presence of vortices enhances the blending of combustion gases and improves the regression rate at both the front and rear ends of the fuel *** addition,oscillations of the regression rate obtained in the simulation can also be well corresponded with the corrugated surface observed in the ***,the zero-dimension regression rate formula and the for-mula describing the axial location dependence of the regression rate are fitted from the simulation results,with the corresponding coefficients of determination(R°)of 0.9765 and 0.9298,*** research serves as a reference for predicting the performance of HRM with gas oxygen and polyethylene,and presents a credible way for investigating the spatiotemporal distribution of the regression rate.

关键词： Hybrid Rocket Motor(HRM) Transient numerical simulation Fluid-solid couplingheat transfer Spatiotemporal distribution of regression rate Dynamic grid

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Different lymph node staging systems for predicting the prognosis of colorectal neuroendocrine neoplasms

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1745-1755页

作者： Yuan-Yi Zhang Yue-wei cai Xia Zhang Department of Pathology Zhaoqing Medical CollegeZhaoqing 526020Guangdong ProvinceChina Department of Emergency Zhaoqing Second People’s HospitalZhaoqing 526020Guangdong ProvinceChina Department of Pathology and Physiology Zhaoqing Medical CollegeZhaoqing 526020Guangdong ProvinceChina

BACKGROUND Colorectal neuroendocrine neoplasms(NENs)are a rare malignancy that primarily arises from the diffuse distribution of neuroendocrine cells in the colon and *** studies have pointed out that the status of lymph node may be used to predict the *** To investigate the predictive values of lymph node ratio(LNR),positive lymph node(PLN),and log odds of PLNs(LODDS)staging systems on the prognosis of colorectal NENs treated surgically,and compare their predictive *** This cohort study included 895 patients with colorectal NENs treated surgically from the Surveillance,Epidemiology,and End Results *** endpoint was mortality of patients with colorectal NENs treated surgically.X-tile software was utilized to identify most suitable thresholds for categorizing the LNR,PLN,and *** were selected in a random manner to form training and testing *** prognosis of surgically treating colorectal NENs was examined using multivariate cox analysis to assess the associations of LNR,PLN,and LODDS with the prognosis of colorectal NENs.C-index was used for assessing the predictive *** conducted a subgroup analysis to explore the different lymph node staging systems’predictive *** After adjusting all confounding factors,PLN,LNR and LODDS staging systems were linked with mortality in patients with colorectal NENs treated surgically(P<0.05).We found that LODDS staging had a higher prognostic value for patients with colorectal NENs treated surgically than PLN and LNR staging *** results were obtained in the different G staging subgroup ***,the area under the receiver operating characteristic curve values for LODDS staging system remained consistently higher than those of PLN or LNR,even at the 1-,2-,3-,4-,5-and 6-year follow-up *** LNR,PLN,and LODDS were found to significantly predict the prognosis of patients with colorectal NENs treated surgically.

关键词： Positive lymph node Lymph node ratio Log odds of positive lymph nodes Prognosis Colorectal neuroendocrine neoplasms

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Research on wind turbine blade damage based on pre-stressed FBG strain sensors

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Optoelectronics Letters 2024年第2期20卷 83-88页

作者： cai Yujie YANG Zhiquan ZHANG Bihua wei Yufeng Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Faculty of Public Safety and Emergency Management Kunming University of Science and TechnologyKunming 650093China Beijing FBGTECH Optic Electric Technology Co. Ltd.Beijing 100043China1

One of the essential parts of a wind power generator that captures wind energy is the wind turbine *** safety of the blades rapidly declines as a wind turbine's operating period *** real-time monitoring,a chip-type pre-stressed fiber Bragg grating(FBG)strain sensor was *** sensor's structure was improved using simulation analysis along with *** was discovered through calibration trials that the pre-stressing method expanded the sensor's range of measurement,guaranteed overall linearity,and prevented the potential hysteresis phenomena during *** sensor's final sensitivity was calculated to be 1.970 pm/με,and its linear fitting coefficient was ***,the sensor was used to monitor the wind turbine blades and the strain change curve of the root of a normally functioning blade is found to be a sine curve,which provides a certain reference value for judging whether the blade is damaged in the future.

关键词： blade strain damage

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Influence of powder oxidation on powder properties and formability in H13 hot-work steels processed by electron beam melting

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Journal of Iron and Steel Research International 2024年第4期31卷 924-932页

作者： wei Liu Yan Wang Li-xiong Han Ying-kang wei Hui-ping Tang Shi-feng Liu School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina School of Engineering Zhejiang University City CollegeHangzhou 310015ZhejiangChina

The oxygen content of metal powder is decisive for the recyclability of *** research on the effect of oxygen content on powder properties and material formability has practical significance for economical production with additive manufacturing while preventing the waste of ***,we deliberately oxidized the powder by baking at high temperature to increase the oxygen content in the powder and gave the calculation method of the oxygen content in the powder oxidation *** majority of oxygen element was found in the oxide particles in the powder and the oxide flm on the powder surface,which did affect the flowability of the *** is worth noting that the increase in the oxygen content does not change the phase of H13 steel,but it can promote the molten pool flow and obtain a smoother *** increase in the oxygen content in the powder is not the decisive factor for the formability and defects of the printed *** is the combined effect of the powder deformation,the increase in the oxygen content,and the impurity pollution after repeated use,which leads to the limitation of repeated utilization of the powder.

关键词： Additive manufacturing Electron beam melting H13 steel powder-Powder oxidation

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Remaining Useful Life Prediction Method for Multi-Component System Considering Maintenance:Subsea Christmas Tree System as A Case Study

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China Ocean Engineering 2024年第2期38卷 198-209页

作者： WU Qi-bing cai Bao-ping FAN Hong-yan WANG Guan-nan RAO Xi GE weifeng SHAO Xiao-yan LIU Yong-hong CNOOC Safety Technology Services Co. Ltd.Tianjin 300456China College of Mechanical and Electronic Engineering China University of PetroleumQingdao 266580China CNOOC EnerTech Safety&Environmental Protection BranchTianjin 300456China

Maintenance is an important technical measure to maintain and restore the performance status of equipment and ensure the safety of the production process in industrial production,and is an indispensable part of prediction and health ***,most of the existing remaining useful life(RUL)prediction methods assume that there is no maintenance or only perfect maintenance during the whole life cycle;thus,the predicted RUL value of the system is obviously lower than its actual operating *** complex environment of the system further increases the difficulty of maintenance,and its maintenance nodes and maintenance degree are limited by the construction period and working conditions,which increases the difficulty of RUL *** RUL prediction method for a multi-omponent system based on the Wiener process considering maintenance is *** performance degradation model of components is established by a dynamic Bayesian network as the initial model,which solves the uncertainty of insufficient data *** on the experience of experts,the degree of degradation is divided according to Poisson process simulation random failure,and different maintenance strategies are used to estimate a variety of condition maintenance *** example of a subsea tree system is given to verify the effectiveness of the proposed method.

关键词： remaining useful life Wiener process dynamic Bayesian networks maintenance subsea Christmas tree system

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Analysis of sensitivity to hydrate blockage risk in natural gas gathering pipeline

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Petroleum Science 2024年第4期21卷 2723-2733页

作者： Ao-Yang Zhang Meng cai Na wei Hai-Tao Li Chao Zhang Jun Pei Xin-wei Wang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Research Institute of Production Engineering Daqing Oilfield Co.Ltd.

During the operational process of natural gas gathering and transmission pipelines, the formation of hydrates is highly probable, leading to uncontrolled movement and aggregation of hydrates. The continuous migration and accumulation of hydrates further contribute to the obstruction of natural gas pipelines, resulting in production reduction, shutdowns, and pressure build-ups. Consequently, a cascade of risks is prone to occur. To address this issue, this study focuses on the operational process of natural gas gathering and transmission pipelines, where a comprehensive framework is established. This framework includes theoretical models for pipeline temperature distribution, pipeline pressure distribution, multiphase flow within the pipeline, hydrate blockage, and numerical solution methods. By analyzing the influence of inlet temperature, inlet pressure, and terminal pressure on hydrate formation within the pipeline, the sensitivity patterns of hydrate blockage risks are derived. The research indicates that reducing inlet pressure and terminal pressure could lead to a decreased maximum hydrate formation rate, potentially mitigating pipeline blockage during natural gas transportation. Furthermore, an increase in inlet temperature and terminal pressure, and a decrease in inlet pressure, results in a displacement of the most probable location for hydrate blockage towards the terminal station. However,it is crucial to note that operating under low-pressure conditions significantly elevates energy consumption within the gathering system, contradicting the operational goal of energy efficiency and reduction of energy consumption. Consequently, for high-pressure gathering pipelines, measures such as raising the inlet temperature or employing inhibitors, electrical heat tracing, and thermal insulation should be adopted to prevent hydrate formation during natural gas transportation. Moreover, considering abnormal conditions such as gas well production and pipeline network s

关键词： Natural gas hydrates Gathering pipeline Temperature variation Hydrate formation rate Sensitivity analysis

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Coupling analysis method of grouting construction with deformation response of adjacent existing tunnel

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Underground Space 2024年第2期15卷 312-330页

作者： ping-wei Jiang Zhi-hong Zhang Hong Zheng Jin-kun Huang Key Laboratory of Urban Security and Disaster Engineering of China Ministry of Education Beijing University of TechnologyBeijing 100124China China MCC17 Group Co.LTD MaanshanAnhui 243000China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

In the new tunnel under close distance through the existing tunnel risk source,the grouting scheme developed to compensate for stratum losses is still based on empirical methods,relying on the overburden thickness of existing *** can potentially lead to an excessively high or low probability of uplift of existing *** a coupled deformation analysis method between the grouting construction and adjacent existing tunnels is of great theoretical significance for developing grouting *** order to reasonably limit the design parameters of grouting construction,based on the theory of fluid–solid coupling elastic pore-column expansion and the theory of random media,the calculation method of stratum displacement which simultaneously considers the coexistence of grout compaction expansion and permeability diffusion mode is derived,and the accuracy of the calculation method is verified by engineering *** accuracy of this calculation method was verified through engineering *** with the deformation coordination condition,the existing tunnel is regarded as an elastic Euler-Bernoulli continuous beam,and the finite element coupling balance equation of the interaction between the existing tunnel and the surrounding soil is *** on this,a coupling calculation model of the grouting construction and the deformation response of the adjacent existing tunnel is *** with three times of grouting construction examples in the shield tunneling project of Beijing Metro Line 12 under the existing airport line,the reliability of the coupling calculation model to determine the grouting construction parameters is *** calculation parameters in the coupling calculation model have clear physical meanings,which can provide a theoretical basis for the grouting design of similar risk source projects.

关键词： Grouting Close-range underpass Tunnel Random medium theory Euler-Bernoulli continuous beam

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