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A 12-month follow-up study of discharged patients with acute pancreatitis:An acute condition with prolonged sequela

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Chinese Medical Journal 2024年第2期137卷 250-252页

作者： Hanyue Ding Jiayuan Dai Jiaye Lin liang gong Han Sun Kai Song Feng Xie Dong Wu Department of Gastroenterology Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical ScienceBeijing 100730China School of Population Medicine and Public Health Peking Union Medical College and Chinese Academy of Medical ScienceBeijing 100730China JC School of Public Health and Primary Care Faculty of MedicineThe Chinese University of Hong KongHong Kong Special Administrative RegionChina Emergency Department Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical ScienceBeijing 100730China Department of Health Research Methods Evidence and ImpactMcMaster UniversityHamiltonCanada Centre for Health Economics and Policy Analysis McMaster UniversityHamiltonCanada State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical ScienceBeijing 100730China Clinical Epidemiology Unit International Clinical Epidemiology NetworkBeijing 100730China

To the Editor:Acute pancreatitis(AP)is the most common gastrointestinal condition that leads to acute hospitalization.[1]The incidence of AP has increased in recent decades,with a current global incidence of 34/100,000,probably due to a rising trend of obesity and gallstone disease.AP is associated with remarkable pain,reduced quality of life(QoL),and even death,thus posing a heavy socioeconomic burden.In addition,approximately 22%of AP patients experience recurrent AP(RAP)and 10%of AP patients progress to chronic pancreatitis.[2]Petrov and Yadav[3]have,therefore,argued that AP should not be considered as an acute and self-limiting disease.Treatment and long-term care after AP have drawn widespread attention,which has improved patients’physical and mental health.

关键词： patients pancreatitis acute

Enhancement of Natural Convection for Cooling Active Antenna Unit Device in 5G Base Station

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Journal of Thermal Science 2022年第5期31卷 1551-1564页

作者： ZHANG Dexin DING Bin ZHU Chuanyong gong liang College of New Energy China University of Petroleum(East China)Qingdao266580China

The Active Antenna Unit(AAU)on the outdoor tower is the key equipment to support the mobile communication of 5G.To suppress the overheating of AAU in summer,effective cooling measures are essential.In the present study,a numerical model of an AAU device with two chips in the outdoor environment was established to explore the surface temperature distribution under a coupling heat transfer process with natural convection and solar radiation was obtained.Moreover,the effects of the fin number,the fin height and the heat flux were discussed on the cooling performance.The results proved that the fins with a number of 12 presented the best cooling performance in this paper.By contrast,increasing the height of fins was still an effective way to improve the cooling performance of fins in outdoor conditions and to resist the thermal shock of chips.Besides,punching through holes on the fins,adding graphite heat spreader and reducing surface emissivity are effective ways to improve the cooling performance.After the optimizations,the maximum temperature decreased by 3.5℃in total.In other words,the contribution of these optimizations to the cooling performance was equivalent to an increase of fin height in 9 mm.

关键词： natural convection heat transfer enhancement structural optimization 5G base station

Toward an Optimum Design of an Amorphous Silicon Photovoltaic/Thermal System:Simulation and Experiments

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Journal of Thermal Science 2023年第3期32卷 947-964页

作者： REN Xiao LI Jing LIU Weixin ZHU Chuanyong PEI Gang gong liang College of New Energy China University of Petroleum(East China)Qingdao 266580China Research Center for Sustainable Energy Technologies Energy and Environment InstituteUniversity of HullHU67RXUK Department of Thermal Science and Energy Engineering University of Science and Technology of ChinaHefei 230026China

Amorphous silicon photovoltaic/thermal(a-Si-PV/T)technology is promising due to the low power temperature coefficient,thin-film property,thermal annealing effect of the solar cells,and high conversion efficiency in summer.The design of a-Si-PV/T system is influenced by a number of thermodynamic,structural,and external parameters.Parametric analysis is useful for a good design of the system.A dynamic distributed parameter model is built and verified in this paper.Outdoor tests are carried out.The impacts of operating temperature,mass flow rate,cover ratio of solar cells,heat transfer area,and frame shadow ratio on its performance are theoretically and experimentally investigated.The results indicate that seven or eight copper tubes are suitable to achieve a high overall efficiency of the a-Si-PV/T system.The frame and tilt angle shall avoid a shadow ratio of more than 8.3%during operation.The difference between power outputs at operating temperatures of 35℃and55℃in the first month is about 0.21%while it drops to less than 0.1%in the twelfth month.Compared with conventional PVT systems,the a-Si-PV/T system benefits from a higher design temperature with a minor efficiency decrement.

关键词： amorphous silicon cell photovoltaic thermal system parametric analysis distributed parameter model frame shadow

Special Column for the 8th Asian Symposium on Computational Heat Transfer and Fluid Flow(ASCHT 2021)

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Journal of Thermal Science 2023年第3期32卷 897-897页

作者： TANG Guihua gong liang School of Energy and Power Engineering Xi'an Jiaotong UniversityChina College of New Energy China University of Petroleum(East China)China

This Special Column of the Journal of Thermal Science(JTS)features a selection of peer-reviewed papers from ASCHT 2021,which was held in Qingdao,China from September 23rdto 26th,2021.The conference was chaired by Professor YAO Jun and Professor gong liang from China University of Petroleum(East China),SUGA Kazuhiko from Osaka Prefecture University,Japan,TANG Guihua from Xi’an Jiaotong University,China,and SON Gihun from Sogang University,Korea.

关键词： ASCH Qingdao Korea

Preparation of nitric humic acid by catalytic oxidation from Guizhou coal with catalysts

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International Journal of Mining Science and Technology 2012年第1期22卷 75-78页

作者： Yang Zhiyuan gong liang Ran Pan School of Chemistry and Chemical Engineering Xi'an University of Sdence and TechnologyXi'an 710054.China

Nitric humic acid was prepared by catalytic oxidation between nitric acid and Guizhou coal, with added catalysts. We investigated catalytic oxidation processes and the factors that affect the reactions. The effects of different catalysts, including NiSO 4 support on active carbon (AC-NiSO 4 ), NiSO 4 support on silicon dioxide (SiO 2 -NiSO 4 ), composites of SO 4 2à /Fe 2 O 3 , Zr-iron and vanadium-iron composite were studied. As well, we investigated nitric humic acid yields and the chemical structure of products by element analysis, FT-IR and E4/E6 (an absorbance ratio at wavelengths of 465 and 665 nm of humic acid alkaline extraction solutions). The results show that the catalytic oxidation reaction with added catalysts can increase humic acid yields by 18.7%, 16.36%, 12.94%, 5.61% and 8.59%, respectively. The highest yield of humic acid, i.e., 36.0%, was obtained with AC-NiSO 4 as the catalyst. The amounts of C and H decreased with the amount of nitrogen. The increase in the E4/E6 ratio in catalytic oxidation of (Guizhou) coal shows that small molecular weights and high yields of nitric humic acid can be obtained by catalytic oxidation reactions.

关键词：催化氧化反应催化剂制备腐植酸贵州煤硝酸 E4/E6值复合材料吸光度比值

Model-based in-situ measurement of pakchoi leaf area

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International Journal of Agricultural and Biological Engineering 2015年第4期8卷 35-42页

作者： gong liang Chen Ran Zhao Yuanshen Liu Chengliang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Leaf area measurement is of great significance in plant growth process monitoring.It poses challenges to perform an unattended in-situ measurement,arising from quantifying the 3-dimensional pakchoi leaf surface.Conventional non-destructive measurement techniques,which usually take its projection on the horizon plane of the leaf area,inevitably cause considerable measurement errors.In order to improve the measurement precision for leaf area,the exemplar pakchoi leaf was modeled as a complete or a piecewise spatial plane to approximate the actual leaf surface,and a machine-vision based ad hoc measuring platform was developed to conduct the in-situ measurement.First,the leaf image was captured by a stereo vision system and segmented via a semi-automatic process to obtain its projective area and spatial inclination angle.Second,pakchoi leaves were modeled as spatial surfaces regarding to their projected counterparts.Third,leaf areas were calculated according to the established planar spatial model,acquired inclination angles and projective areas.The experimental comparison among the lattice-based monotype method,projection method,and the model-based method,whose results are denoted as MA,PA,and EA respectively,showed that the proposed framework could simultaneously meet the accuracy and non-destructive measurement requirements.The constructed platform also provided a cost-effective semi-automatic measurement approach for continuously in-situ monitoring of pakchoi growth during its whole cultivation period.It is further suggested from the experimental results that the proposed methodology can offer a generic measurement solution to various kinds of plant physiological and ecological studies in future researches.

关键词： leaf area in-situ measurement non-destructive measurement stereo vision image processing

Thermal Performance and Mechanics Characteristic for Double Layer Microchannel Heat Sink

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Journal of Thermal Science 2019年第2期28卷 271-282页

作者： XU Yupeng gong liang LI Yongtong BAI Zhang XU Minghai Department of Energy & Power Engineering China University of Petroleum (East China)

Double layer micro-channel heat sink(DLMCHS) has been widely used in various electronic devices; however, the existence of the nonuniform thermal strain distribution in actual operation has adverse effect on the overall stability. In this paper, two optimized designs of DLMCHS with cutting baffles on top and bottom layers are presented based on the traditional DLMCHS. The heat transfer and thermal stress performance are numerically analyzed and compared with the traditional DLMCHS. The results indicate that cutting baffles of micro-channels remarkably improves heat transfer and thermal stress performance. The optimized design with cutting baffles on the bottom layer decreases thermal strain but deteriorates heat transfer performance. The model with cutting baffles on the top layer has better combined thermal strain and heat transfer performance, which reduces thermal strain by about 1.5 times and enhances heat transfer by about 26.5%. For the design with cutting baffles on the top board, adding metal foam in the inlet collector can decrease the total minimum thermal strain by 51.4% and maximum temperature by 1.4 K, and increase the Nusselt number by 15%. These results indicate that DLMCHS with cutting baffles on the top layer has great potential for thermal managements on electronic devices with high power density.

关键词： double layer micro-channel heat sink thermal strain thermal performance optimized design

Phase Prediction of Supercritical Carbon Dioxide and its Application in Fracturing Oil Wellbores

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Journal of Thermal Science 2019年第3期28卷 484-493页

作者： gong liang CHEN Shichao ZUO Jiaqiang BAI Bin BAI Zhang College of Pipeline and Civil Engineering China University of Petroleum (East China) School of Petroleum Engineering China University of Petroleum (East China) Petroleum Engineering Technology Research Institute Sinopec Shengli oil field

In recent oil and gas exploration, the most reservoirs are low permeability with abundant reserves. Conventional mining of low permeability reservoir is commonly utilizing the hydraulic fracturing technology, whereas, it encounters various technical issues, such as clay expansion and water lock damage. Using the fluid of supercritical carbon dioxide(S-CO_2) to exploit the low permeability oil and gas reservoirs is attracting more attention. The implementation of S-CO_2, without liquid phase, can help avoid the aforementioned problems. Nevertheless, the phase change of CO_2 during fracturing is complicate, and it is difficult to accurately predict the CO_2 phase transition. In this work, first, the physical properties of S-CO_2 were analyzed by the Span-Wagner model and Vesovic model. Next, S-CO_2 was applied to a typical oilfield, and an unsteady coupling model of heat transfer and pressure drop was developed. Then the staggered grid method and iteration procedures were used for numerical solutions, and the temperature and pressure distributions of wellbores were investigated. The results indicate that the temperature control of a wellbore is the key to the phase prediction of S-CO_2; CO_2 within the single-diameter pipeline below 2300 m can maintain the supercritical state, while CO_2 within the stepped pipeline can maintain the supercritical state at the depth of 2280 m. Moreover, compared with the single-diameter pipeline, the bottom pressure of the stepped pipeline is lower and the bottom temperature is higher. By analyzing the flow and heat transfer of S-CO_2 in the wellbores, the phase state of S-CO_2 was well predicted, which is helpful to improve the exploring performance of low permeability oil and gas reservoirs.

关键词： supercritical carbon dioxide unsteady-state heat transfer phase prediction wellbore

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小肠胃黏膜异位的临床特点并文献复习

中华医学杂志 2024年第21期104卷 1998-2002页

作者：范正阳龚亮胡文墨刘炜游燕吴东中国医学科学院北京协和医院消化内科疑难重症及罕见病全国重点实验室北京中国医学科学院北京协和医院放射科疑难重症及罕见病全国重点实验室北京中国医学科学院北京协和医院病理科疑难重症及罕见病全国重点实验室北京

总结小肠胃黏膜异位患者的临床表现, 并通过文献复习比较国内外患者的临床表现差异。回顾性分析北京协和医院自2000年1月至2024年1月确诊为小肠胃黏膜异位的病例的临床特征。通过检索Pubmed、EMBASE、the Cochrane Library、万方、维普... 详细信息

总结小肠胃黏膜异位患者的临床表现, 并通过文献复习比较国内外患者的临床表现差异。回顾性分析北京协和医院自2000年1月至2024年1月确诊为小肠胃黏膜异位的病例的临床特征。通过检索Pubmed、EMBASE、the Cochrane Library、万方、维普、知网等数据库;纳入时间为自数据库建库至2024年1月1日, 对小肠胃黏膜异位进行文献复习。共纳入10例患者, 均为男性, 年龄[M(Q1, Q3)]为27(13～69)岁。病例多以消化道出血为首发表现, 严重者出现失血性休克。腹部CT提示3例患者局部小肠壁增厚及肠腔狭窄。4例病变位于空肠起始段, 6例位于回肠末段。所有病例均接受了局部病变切除术, 术后病理证实为小肠胃黏膜异位。术后所有患者症状均消失, 随访时间为0.5～3.0年。文献复习提示我国小肠胃黏膜异位临床主要表现为消化道出血;而国外患者多合并肠道重复畸形, 并引发肠套叠, 临床多以腹痛、呕吐为首发及主要表现。国内外女性患者肠梗阻发生率均高于男性;国内外患者回肠病变肠梗阻及合并小肠重复畸形的发生率高于空肠病变。局部小肠切除术是有效治疗方式, 多预后良好。小肠胃黏膜异位较为罕见, 消化道出血及肠梗阻症状为常见表现, 可作为不明原因消化道出血的鉴别病因之一。

关键词：胃黏膜消化道出血失血性休克肠梗阻