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The estimate of sensitivity for large infrared telescopes based on measured sky brightness and atmospheric extinction

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Research in Astronomy and Astrophysics 2021年第4期21卷 101-109页

作者： Zhi-Jun Zhao Hai-Jing Zhou yu-chen zhang yun Ling Fang-yu Xu School of Physics Henan Normal UniversityXinxiang 453007China yunnan Observatories Chinese Academy of SciencesKunming 650216China Kunming Institute of Physics Kunming 650216China Henan Key Laboratory of Infrared Materials&Spectrum Measures and Applications Xinxiang 453007China

In order to evaluate the ground-based infrared telescope sensitivity affected by the noise from the atmosphere,instruments and detectors,we construct a sensitivity model that can calculate limiting magnitudes and signal-to-noise ratio(S/N).The model is tested with tentative measurements of M’-band sky brightness and atmospheric extinction obtained at the Ali and Daocheng *** find that the noise caused by an excellent scientific detector and instruments at-135℃can be ignored compared to the M’-band sky background ***,when S/N=3 and total exposure time is 1 second for 10 m telescopes,the magnitude limited by the atmosphere is 13.01^(m)at Ali and 12.96^(m)at *** under lessthan-ideal circumstances,i.e.,the readout noise of a deep cryogenic detector is less than 200 e-and the instruments are cooled to below-87.2℃,the above magnitudes decrease by 0.056^(m)at ***,according to observational requirements with a large telescope in a given infrared band,astronomers can use this sensitivity model as a tool for guiding site surveys,detector selection and instrumental thermal-control.

关键词： methods:miscellaneous atmospheric effects telescopes site testing instrumentation:detectors instrumentation:miscellaneous

Simulation aided hot zone design for faster growth of CZ silicon mono crystals

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Rare Metals 2011年第2期30卷 155-159页

作者： CAO Jianwei GAO yu chen Ying zhang Guohu QIU Minxiu The State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China GRINM Semiconductor Materials Co. Ltd Beijing 100088 China

Computer simulation was used for optimizing a hot zone for Czochralski （CZ） silicon crystal growth. The heater structure and heat shield material were investigated. With this optimized hot zone, the temperature gradient near the crystal/melt interface increased and the CZ crystal could be grown at a faster rate. It is a great contribution for saving power consumption.

关键词： crystal growth silicon computer simulation temperature gradient

Computed tomography enterography-based radiomics for assessing mucosal healing in patients with small bowel Crohn's disease

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World Journal of Gastroenterology 2025年第3期31卷 62-72页

作者： Hao Ding yuan-yuan Fang Wen-Jie Fan chen-yu zhang Shao-Fei Wang Jing Hu Wei Han Qiao Mei Department of Gastroenterology The First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Radiation Oncology The First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Gastroenterology Suzhou First People's HospitalSuzhou 234099Anhui ProvinceChina

BACKGROUND Mucosal healing(MH)is the major therapeutic target for Crohn's disease(CD).As the most commonly involved intestinal segment,small bowel(SB)assessment is crucial for CD ***,it poses a significant challenge due to its limited accessibility through conventional endoscopic *** To establish a noninvasive radiomic model based on computed tomography enterography(CTE)for MH assessment in SBCD *** Seventy-three patients diagnosed with SBCD were included and divided into a training cohort(n=55)and a test cohort(n=18).Radiomic features were obtained from CTE images to establish a radiomic *** demographics were analysed to establish a clinical model.A radiomic-clinical nomogram was constructed by combining significant clinical and radiomic *** diagnostic efficacy and clinical benefit were evaluated via receiver operating characteristic(ROC)curve analysis and decision curve analysis(DCA),*** Of the 73 patients enrolled,25 patients achieved *** radiomic-clinical nomogram had an area under the ROC curve of 0.961(95%confidence interval:0.886-1.000)in the training cohort and 0.958(0.877-1.000)in the test cohort and provided superior clinical benefit to either the clinical or radiomic models alone,as demonstrated by *** These results indicate that the CTE-based radiomic-clinical nomogram is a promising imaging biomarker for MH and serves as a potential noninvasive alternative to enteroscopy for MH assessment in SBCD patients.

关键词： Crohn’s disease Computed tomography enterography Mucosal healing Nomogram Radiomics

Axially Chiral Aryl-Alkene-lndole Framework: A Nascent Member of the Atropisomeric Family and Its Catalytic Asymmetric Construction

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Chinese Journal of Chemistry 2020年第6期38卷 543-552页

作者： Cong-Shuai Wang Tian-Zhen Li Si-Jia Liu yu-chen zhang Shuang Deng Yinchun Jiao Feng Shi School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhouJiangsu 221116China Key Laboratory of Theoretical Organic Chemistry and Functional Molecule Ministry of EducationSchool of Chemistry and Chemical EngineeringHunan University of Science and TechnologyXiangtanHunan 411201China

A new class of axially chiral aryl-alkene-indole frameworks have been designed,and the first catalytic asymmetric construction of such scaffolds has been established by the strategy of organocatalytic(Z/E)-selective and enantioselective(4+3)cyclization of 3-alkynyl-2-indolylmethanols with 2-naphthols or phenols(all>95:5 E/Z,up to 98% yield,97% ee).This reaction also represents the first catalytic asymmetric construction of axially chiral alkene-heteroaryl scaffolds,which will add a new member to the atropisomeric *** approach has not only confronted the great challenges in constructing axially chiral alkene-heteroaryl scaffolds but also provided a powerful strategy for the enantioselective construction of axially chiral aryl-alkene-indole frameworks.

关键词： chiral Catalytic asymmetric

Prospects for clinical applications of butyrate-producing bacteria

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World Journal of Clinical Pediatrics 2021年第5期10卷 84-92页

作者： Li-Bin Zhu yu-chen zhang Han-Hui Huang Jing Lin Department of Pediatric Surgery The Second Affiliated Hospital&Yuying Children’s Hospital of Wenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina Department of Pediatric Surgery The Second School of Clinical MedicineWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina Department of Pediatrics Icahn School of Medicine at Mount SinaiNew YorkNY 10029United States

As the major source of energy for colonic mucosal cells and as an important regulator of gene expression,inflammation,differentiation,and apoptosis in host cells,microbiota-derived butyrate can enhance the intestinal mucosal immune barrier,modulate systemic immune response,and prevent *** a certain level of butyrate production in the gut can help balance intestinal microbiota,regulate host immune response,and promote the development and maintenance of the intestinal mucosal ***-producing bacteria act as probiotics and play important roles in a variety of normal biological *** supplementation by using fecal microbiota transplantation to restore butyrate-producing commensal bacteria in the gut has been very successful in the treatment of recurrent and refractory Clostridium difficile(***)infection or ***-negative nosocomial *** of probiotics that include butyrate-producing bacteria may have a role in the treatment of inflammatory bowel diseases and in the prevention of necrotizing enterocolitis and late-onset sepsis in premature ***,modulating gut microbiota with dietary approaches may improve intestinal dysbiosis commonly seen in patients with obesity-associated metabolic *** with a butyrate-producing bacterial stain might be used to increase energy expenditure,improve insulin sensitivity,and to help control obesity and metabolic syndrome.

关键词： Butyrate Butyrate-producing bacteria Gut microbiota Intestinal mucosal barrier Metabolic syndrome Probiotics

Toolbox of teaching strategies

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Frontiers of Nursing 2018年第4期5卷 249-255页

作者： Lei Pan Hui-Qin Xi Xiao-Wei Shen chen-yu zhang Rheumatology Department Renji Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Orthopedics Department School of Medicine Ninth Hospital Affiliated to Shanghai Jiao Tong University

A teaching strategy is a method, which can help students to gain knowledge, deliver information, and improve their learning. Different learning environments, such as clinical teaching, online teaching, and face-to-face traditional learning environments, require different teaching strategies for students. Choosing teaching strategies for a course is very important for nurse educators because various factors should be taken into account to make students meet the learning outcomes. The use of modern technologies in teaching strategies can improve students’ competencies and confidences. The purpose of this article is to create a toolbox integrating ten teaching strategies that can be used in different teaching environments.

关键词： Teaching strategies nursing education student centered learning outcomes review

Catalytic Asymmetric Diastereodivergent Synthesis of 2-Alkenylindoles Bearing both Axial and Central Chirality

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Precision Chemistry 2024年第5期2卷 208-220页

作者： Shuang Yang Jia-Bo Huang Da-Hua Wang Ning-Yi Wang yu-yu chen Xin-Yan Ke Hao chen Shao-Fei Ni yu-chen zhang Feng Shi Research Center of Chiral Functional Heterocycles School of Chemistry and Materials ScienceJiangsu Normal UniversityXuzhou 221116China Department of Chemistry Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong ProvinceShantou UniversityShantou 515063China Department of Otolaryngology Xuzhou First People’s HospitalAffiliated Xuzhou Municipal Hospital of Xuzhou Medical UniversityXuzhou 221002China School of Petrochemical Engineering Changzhou UniversityChangzhou 213164China

The catalytic asymmetric diastereodivergent synthesis of axially chiral 2-alkenylindoles was established via chiral phosphoric acid-catalyzed addition reactions of C3-unsubstituted 2-alkenylindoles with o-hydroxybenzyl alcohols under different reaction *** this strategy,two series of 2-alkenylindoles bearing both axial and central chirality were synthesized in a diastereodivergent fashion with moderate to high yields and good stereoselectivities(up to 99%yield,95:5 er,>95:5 dr).Moreover,theoretical calculations were performed on the key transition states leading to different stereoisomers,which provided an in-depth understanding of the origin of the observed stereoselectivity and diastereodivergence of the products under different reaction *** importantly,these 2-alkenylindoles were utilized in asymmetric catalysis as chiral organocatalysts and in medicinal chemistry for evaluation of their cytotoxicity,which demonstrated their potential *** study has not only established the catalytic atroposelective synthesis of axially chiral 2-alkenylindoles,but also provided an efficient strategy for catalytic asymmetric diastereodivergent construction of indole-based scaffolds bearing both axial and central chirality.

关键词： 2-Alkenylindole Axial chirality Central chirality Diastereodivergent synthesis Chiral phosphoric acid

A new structure of substage in pipelined analog-to-digital converters

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The Journal of China Universities of Posts and Telecommunications 2009年第1期16卷 86-90页

作者： JIA Hua-yu , chen Gui-can, zhang Hong Institute of Microelectronics, Xi’an Jiaotong University, Xi’an 710049, China [a]Institute of Microelectronics Xi'an Jiaotong University Xi'an 710049 China

The article presents a new （1＋1）-bit/stage structure for pipelined analog-to-digital converters （ADC）. When the input analog signal of the structure exceeds the converting range of the whole ADC, the signal can still be converted precisely and the output residue voltage of the structure will be in the converting range of the ADC. The structure is used in a 12-bit 40 MS/s pipelined ADC to test its function. The testing results show that the structure has right function and can correct the transition error induced by offset of comparators＇ decision levels. The ADC implemented in Semiconductor Manufactory International Corporation （SMIC） 0.18 μm CMOS process consumes 210 mW and occupies a chip area of 3.2×3.7 mm2.

关键词： digital correction pipelined ADC residue voltag.e operational amplifier

Analysis of Micromechanical Properties at the Interface of Pre-wet SBS Modified Asphalt Mixture Based on Molecular Simulation Technology

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 103-113页

作者： chen Wuxing chen Shuang yu Yan zhang Jiangyi XU Haiyang GUO Wei School of Mines China University of Mining and TechnologyXuzhou 221000China College of Construction Engineering Jilin Uni-versityChangchun 130026China

The pre-wetting of aggregate surface is a means to improve the interface performance of SBS modified asphalt and *** effect of pre-wetting technology on the interaction between SBS modified asphalt and aggregate was analyzed by molecular dynamics *** diffusion coefficient and concentration distribution of SBS modified asphalt on aggregate surface are *** simulation results show that the diffusion coefficient of the aggregate surface of SBS modified asphalt is increased by 47.6%and 70.5%respectively after 110#asphalt and 130#asphalt are *** concentration distribution of SBS modified asphalt on the aggregate surface after pre-wetting is more *** to the results of interface energy calculation,the interface energy of SBS modified bitumen and aggregate can be increased by about 5%after *** to the results of molecular dynamics simulation,the pre-wetting technology can effectively improve the interface workability of SBS modified bitumen and aggregate,so as to improve the interface performance.

关键词： pre-wet oil-stone interface interface interaction interface mechanics molecular dynamics simulation