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Frontiers of Environmental Science & Engineering 2017年第6期11卷 161-169页

作者： Bai-hang Zhao Jie Chen Han-Qing Yu zhen-Hu Hu zheng-Bo Yue Jun Li Department of Municipal Engineering Beijing University of Technology Beijing 100124 China Department of Chemistry University of Science & Technology of China Hefei 230026 China School of Civil Engineering Hefei University of Technology Hefei 230092 China

The effect of microwave pretreatment on the anaerobic degradation of hyacinth was investigated using response surface methodology （RSM）. The components oflignin and the other constituents of hyacinth were altered by microwave pretreatment. Comparison of the near-infrared spectra of hyacinth pretreated by microwave irradiation and water-heating pretreatment revealed that no new compounds were generated during hyacinth pretreatment by microwave irradiation. Atomic force microscopy observations indicated that the physical structures of hyacinth were disrupted by microwave pretreatment. The yield of methane per gram of the microwave-irradiated substrate increased by 38.3% as compared to that of the substrate pretreated via water-heating. A maximum methane yield of 221 mL·g-sub^-1 was obtained under the optimum pretreatment conditions （substrate concentration （pSC） = 20.1 g·L^-1 and pretreatment time （PT） = 14.6 min） using RSM analysis. A maximum methane production rate of 0.76 mL·h^-1· g-sub^-1 was obtained by applying PSC = 9.5 g·L^-1 and PT= 11 min. Interactive item coefficient analysis showed that methane production was dependent on the PSC and PT, separately, whereas the interactive effect of the PSC and PT on methane production was not significant. The same trend was also observed for the methane production rate.

关键词： Microwave pretreatment Response surface methodology Methane production Hyacinth Anaerobic digestion

Analysis of Wind Power Assessment Based on the WRF Model

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Atmospheric and Oceanic Science Letters 2014年第2期7卷 126-131页

作者： LI Ji-hang GUO zhen-Hai WANG Hui-Jun LI Ji-hang WANG Hui-Jun Nansen-Zhu International Research Centre (NZC) Institute of Atmospheric Physics the Chinese Academy of Sciences Beijing 100029 China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China University of the Chinese Academy of Sciences Beijing 100049 China

Assessing wind energy is a key step in selecting a site for a wind farm. The accuracy of the assessment is essential for the future operation of the wind farm. There are two main methods for assessing wind power: one is based on observational data and the other relies on mesoscale numerical weather prediction(NWP). In this study, the wind power of the Liaoning coastal wind farm was evaluated using observations from an anemometer tower and simulations by the Weather Research and Forecasting(WRF) model, to see whether the WRF model can produce a valid assessment of the wind power and whether the downscaling process can provide a better evaluation. The paper presents long-term wind data analysis in terms of annual, seasonal, and diurnal variations at the wind farm, which is located on the east coast of Liaoning Province. The results showed that, in spring and summer, the wind speed, wind direction, wind power density, and other main indicators were consistent between the two methods. However, the values of these parameters from the WRF model were significantly higher than the observations from the anemometer tower. Therefore, the causes of the differences between the two methods were further analyzed. There was much more deviation in the original material, National Centers for Environmental Prediction(NCEP) final(FNL) Operational Global Analysis data, in autumn and winter than in spring and summer. As the region is vulnerable to cold-air outbreaks and windy weather in autumn and winter, and the model usually forecasted stronger high or low systems with a longer duration, the predicted wind speed from the WRF model was too large.

关键词： wind power assessment anemometer tower data WRF model variance analysis

Studies on bio-oxidation of coal mine gas by a biofilter

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Journal of Coal Science & Engineering(China) 2010年第4期16卷 367-374页

作者： YU Hai-xia MIN hang LUE zhen-mei hangzhou Environmental Monitoring Center Station Hangzhou 310007 China College of Life Science Zhejiang University Hangzhou 310058 China

A new biofilter technology was used to control the methane concentration in the coal mine. The results indicate that the biofilter achieves a steady methane removal capacity of 1 470 mg/（Loh） after 30 days start-up. More than 90% of the methane can be removed with an empty bed retention time （EBRT） of 5.6 min when the inlet concentration of methane （IMC） is lower than 70 mg/L （10%, V/V） and about 80% when IMC is at 105 mg/L （15%, V/V）. The biofilter is still a reliable method to control methane concentration as an auxiliary means to boost coal mine production safety together with aggrandized ventilation and drainage technologies, even though the removal efficiency of methane is not very satisfactory with a high IMC （〉10%） or a short EBRT （〈3.8 min）.

关键词： biofilter bio-oxidation coal mine gas methane methanotroph

Mixed neuroendocrine-nonneuroendocrine neoplasm of the ampulla:Four case reports

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World Journal of Clinical Cases 2022年第7期10卷 2268-2274页

作者： Yang Wang zhen Zhang Cheng Wang Shi-hang Xi Xiao-Ming Wang Department of hepatobiliary Surgery The First Affiliated Hospital of Wannan Medical CollegeWuhu 241000Anhui ProvinceChina

BACKGROUND Mixed neuroendocrine-nonneuroendocrine neoplasm(MiNEN)is a rare tumor that occurs in the gastrointestinal tract and pancreas,usually composed of adenocarcinoma and neuroendocrine *** occurring in ampulla is even *** report 4 cases of MiNEN in ampulla,combined with literature review to summarize the clinical features and treatment of the disease,in order to improve the understanding of the *** SUMMARY A retrospective analysis was performed in 4 cases of MiNEN of the ampulla diagnosed by pathology from 2014 to *** 4 patients were all male,aged 67-81 years(average 72.25 years).Among them,2 patients had jaundice,1 patient had abdominal pain,and 1 patient had jaundice with abdominal pain as the first *** 4 patients underwent enhanced CT or MRI,which all indicated that the tumors were located in the *** patients underwent duodenoscopy,and a biopsy revealed ampullary *** 4 patients underwent radical *** cases were followed up:One patient developed severe complications after the operation,his condition deteriorated,and he survived for 1 *** the other 3 patients,tumor recurrence was observed during follow-up,and 2 of them survived for 29 mo and 22 mo *** case survived and is still being followed *** MiNEN of the ampulla are extremely rare,lacking typical clinical symptoms and imaging features,and are usually diagnosed after postoperative histopathological and immunohistochemical *** main treatment is radical surgical resection,which can be combined with *** best method of diagnosis and treatment needs further research.

关键词： Ampulla Mixed neuroendocrine-nonneuroendocrine neoplasm Pan-creaticoduodenectomy Chemotherapy Case report

Mapping the landscape of gastric signet ring cell carcinoma:Overcoming hurdles and charting new paths for advancement

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World Journal of Clinical Oncology 2025年第2期16卷 94-109页

作者： Shu-Yuan Wang Jing-hang Wang Run-Kai Chen zhen Yuan Hao Cui Bo Wei Jian-Xin Cui School of Medicine Nankai UniversityTianjin 300071China Department of General Surgery The First Medical CenterChinese PLA General HospitalBeijing 100853China

BACKGROUND In recent years,the global prevalence of gastric cancer(GC)has witnessed a progressive decrease,accompanied by a step-growth in the incidence of gastric signet ring cell carcinoma(GSRCC).As precision medicine concepts progress,GSRCC,a distinct sub-type of GC,has drawn considerable attention from ***,there still persist some controversies regarding the associated research *** To summarize the current obstacles and potential future directions for research on *** To begin with,all literature related to GSRCC published from January 1,2004 to December 31,2023 was subjected to bibliometric analysis in this ***,this paper analyzed the research data using CiteSpace,GraphPad Prism v8.0.2,and VOSviewer,which was obtained from the Web of Science Core Collection *** analysis results were visually *** This study provided a comprehensive overview of the statistical characteristics of the 995 English articles related to GSRCC,including cited references,authors,journals,countries,institutions,and *** popular keywords and clusters contain"prognosis","survival","expression","histology",and"chemotherapy".CONCLUSION The prognosis,precise definition and classification,as well as chemoresistance of GSRCC,continue to be crucial areas of ongoing research,whose directions are closely tied to advancements in molecular biology research on GSRCC.

关键词： Gastric cancer Signet ring cell carcinoma Bibliometric analysis CiteSpace VOSviewer

Quality of life after pancreatic surgery

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World Journal of Gastroenterology 2024年第8期30卷 943-955页

作者： Shi-zhen Li Ting-Ting zhen Yi Wu Min Wang Ting-Ting Qin hang Zhang Ren-Yi Qin Department of Biliary-Pancreatic Surgery Affiliated Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina

BACKGROUND Pancreatic surgery is challenging owing to the anatomical characteristics of the *** attention has been paid to changes in quality of life(QOL)after pancreatic *** To summarize and analyze current research results on QOL after pancreatic *** A systematic search of the literature available on PubMed and EMBASE was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses *** studies were identified by screening the references of retrieved *** on patients’QOL after pancreatic surgery published after January 1,2012,were *** included prospective and retrospective studies on patients'QOL after several types of pancreatic *** results of these primary studies were summarized *** A total of 45 articles were included in the study,of which 13 were related to pancreaticoduodenectomy(PD),seven to duodenum-preserving pancreatic head resection(DPPHR),nine to distal pancreatectomy(DP),two to central pancre-atectomy(CP),and 14 to total pancreatectomy(TP).Some studies showed that 3-6 months were needed for QOL recovery after PD,whereas others showed that 6-12 months was more *** TP and PD had similar influences on QOL,patients needed longer to recover to preoperative or baseline levels after *** QOL was better after DPPHR than ***,the superiority of the QOL between patients who underwent CP and PD remains *** decrease in exocrine and endocrine functions postoperatively was the main factor affecting the *** invasive surgery could improve patients’QOL in the early Core Tip:This review summarizes and analyzes current research results on quality of life(QOL)after pancreatic *** article covers the discussion and analysis of the QOL of various pancreatic *** kind of surgical procedure has better QOL is *** long-term benefits on QOL of minimally invasive su

关键词： Quality of life Pancreaticoduodenectomy Duodenum-preserving pancreatic head resection Distal pancreatectomy Central pancreatectomy Total pancreatectomy

Effect of Nb Content on the Hot Deformation Behavior of S460ML Steel

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Acta Metallurgica Sinica(English Letters) 2019年第4期32卷 526-534页

作者： Yu-Cheng Zhang zhen-Sheng Meng Yang Meng Xin-Hua Ju Zhong-hang Jiang Ze-Jun Ma Research Institute of Technology of Shougang Group Co.Ltd.

The hot deformation behavior of S460 ML steel with different Nb contents was investigated by single-pass compression experiment on the Gleeble-1500 thermo-machine simulator at deformation temperatures ranging from 900 to 1200 ℃ and strain rates from 0.1 to 5.0 s^(-1). The critical strain of dynamic recrystallization(DRC) under different conditions was determined by using working hardening rate-strain curves. The relationship between critical strain and peak strain of DRC was discussed. By means of regression analysis method, the hot deformation activation energy of steels and the mathematical model for predicting DRC critical strain were calculated and established, respectively. The results showed that DRC occurred during hot deformation. As the deformation temperature increased and strain rate decreased, the critical strain of DRC decreased. The critical strain(εc) showed linear relationship with peak strain(εp). As Nb content increased,the needed deformation temperature for occurring DRC increased, while the needed strain rate for it decreased. The activation energy for hot deformation of S460 ML steel increased with increasing Nb content.

关键词： Dynamic recrystallization Critical strain Nb content Deformation temperature Strain rate Hot deformation

Microstructure and high-temperature wear properties of in situ TiC composite coatings by plasma transferred arc surface alloying on gray cast iron

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1273-1282页

作者： hang Zhao Jian-jun Li Zhi-zhen zheng Ai-hua Wang Qi-wen Huang Da-wen Zeng State Key Laboratory of Material Processing and Die & Mould Technology Huazhong University of Science & Technology

In this work, an in situ synthesized TiC-reinforced metal matrix composite （MMC） coating of approximately 350-400μm thickness was fabricated on a gray cast iron （GCI） substrate by plasma transferred arc （PTA） surface alloying of Ti-Fe alloy powder. Microhard- ness tests showed that the surface hardness increased approximately four-fold after the alloying treatment. The microstructure of the MMC coating was mainly composed of residual austenite, acicular martensite, and eutectic ledeburite. Scanning electron microscopy （SEM） and X-ray diffraction analyzes revealed that the in situ TiC particles, which were formed by direct reaction of Ti with carbon originally contained in the GCI, was uniformly distributed at the boundary of residual anstenite in the alloying zone. Pin-on-disc high-temperature wear tests were performed on samples both with and without the MMC coating at room temperature and at elevated temperatures （473 K and 623 K）, and the wear behavior and mechanism were investigated. The results showed that, after the PTA alloying treatment, the wear resistance of the sam- ples improved significantly. On the basis of our analysis of the composite coatings by optical microscopy, SEM with energy-dispersive X-ray spectroscopy, and microhardness measurements, we attributed this improvement of wear resistance to the transformation of the microstruc- ture and to the presence of TiC particles.

关键词： gray cast iron composite coatings particle-reinforced composites titanium carbide surface alloying microstructure wear

Design and catalytic atroposelective synthesis of axially chiral isochromenone-indoles

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Science China Chemistry 2022年第10期65卷 1929-1937页

作者： Qing-Qing hang Shu-Fang Wu Shuang Yang Xue Wang zhen Zhong Yu-Chen Zhang Feng Shi Research Center of Chiral Functional heterocycles School of Chemistry&Materials ScienceJiangsu Normal UniversityXuzhou 221116China School of Petrochemical Engineering Changzhou UniversityChangzhou 213164China

The catalytic atroposelective synthesis of axially chiral isochromenone-indoles has been established by the strategy of designing homophthalic anhydride-based indole derivatives as a new type of indole-based platform molecules for dynamic kinetic *** this strategy,a wide range of axially chiral isochromenone-indoles were synthesized in high yields with excellent enantioselectivities(up to 98% yield,97% ee) via the catalytic asymmetric sulfonylation reaction of homophthalic anhydridebased indole derivatives with aryl sulfonyl chlorides under the catalysis of chiral quaternary ammonium salt as a phase-transfer catalyst.

关键词： asymmetric organocatalysis axial chirality atroposelectivity enantioselectivity indole

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Influence of Nd^(3+) concentration on mid-infrared emission in PbF_(2) crystal co-doped with Ho^(3+) and Nd^(3+) ions

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Journal of Rare Earths 2024年第3期42卷 479-487,I0002页

作者： Yan Chen Juncheng Tan Peixiong Zhang Weibi zheng Lin Li Lianhan Zhang zhen Li Yin hang zhenqiang Chen Department of Optoelectronic Engineering Jinan UniversityGuangzhou510632China Guangdong Provincial Engineering Research Centerof Crystal and Laser Technology.Guangzhou 510632China Research Center of Laser Crystal Key Laboratory of High Power Laser MaterialsShanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai201800China

A promising series of Ho_(y)Nd_(x)Pb_((1-x-y))F_2(x = 0, 0.01, 0.02, 0.03, 0.04;y = 0.02) crystals was grown by the Bridgman method. The influence of the Nd^(3+)ions concentration on mid-infrared(~2.0, ~2.9 and ~3.9 μm)fluorescence emissions of Ho^(3+)ions in the PbF_(2) crystal excited by 808 nm laser diode was investigated in this work. The energy transfer mechanism between Nd^(3+)ions and Ho~(3+)ions under different concentrations of the Nd^(3+)ions was systematically analyzed. The results show that the Nd^(3+)ions have good sensitization and deactivation effect on the Ho^(3+)ions to stimulate the mid-infrared fluorescence emissions. The experimental analysis proves that the sensitization efficiency of the Nd^(3+)ions is relatively stable at around 93.45% with varying Nd^(3+)-doping concentrations. Concentration dependence studies indicate that the concentration of the Nd^(3+)ions has significant influence on mid-infrared *** the doping concentration of the Nd^(3+)ions is up to 2.0 at%, the intensity of ~2.0, ~2.9 and ~3.9 μm emissions all reach the maximum. The output characteristics of a 3.9 μm laser are simulated, and it is found that with the increase of the Nd^(3+)-doping concentration, the peak power, pulse width, and peak energy all meet the trend of first increasing and then decreasing, and Ho_(0.02)Nd_(0.02)Pb_(0.96)F_(2) crystal displays the best performance. All the results show that the Nd^(3+)/Ho^(3+)co-doped PbF_(2) crystals might act as a useful optical medium for mid-infrared laser applications.

关键词： Crystal growth Mid-infrared PbF_(2) Rare earth ions