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Experiment of drag characteristics of a novel variable geometry flame-holder

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航空动力学报 2011年第11期26卷 2485-2494页

作者： liu yang jin Jie WANG Hui-ru liu Yu-ying yang Mao-lin School of Jet Propulsion Beijing University of Aeronautics and AstronauticsBeijing 100191China

A novel variable geometry flame-holder(VGF) based on V-gutter was *** structural characteristics of the flame holder were *** study on drag characteristics of the VGF on un-burning and burning states was conducted in a rectangular combustion test *** influence of the change of gutter trailing edge width w on pressure recovery in different operating conditions was analyzed ***,drag characteristics in different trailing edge width variation modes were *** show that:(1) Narrowing w can observably raise the total pressure recovery σ but the highest σ is not obtained at minimum w.(2) The relationship of drag coefficient ψ and w in the un-burning conditions can be well expressed in a form of exponential equation(w/d>0.4).(3) Drag characteristics are not sensitive to the variation modes and speeds of w.(4) In the burning condition,σ decreases with the increasing of w basically and the course can be divided into three *** results and experimental data presented in this paper would enhance the phenomenological understanding of this type of VGF,and would contribute to the next experimental study and numerical calculus of this novel VGF.

关键词： flame-holder variable geometry afterburner augmentor drag characteristics

中国农业现代化发展的空间格局演化及驱动因素分析

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山东农业大学学报（社会科学版） 2024年第1期26卷 88-96页

作者：龙一萍刘锦扬李胜成都信息工程大学统计学院成都610199

党的二十大强调坚持和完善以农业农村为重点的乡村振兴战略,提出加快农业现代化。因此,从生产现代化、经营现代化、可持续发展现代化3个维度构建农业现代化发展水平指标体系,使用熵值法对2013-2021年中国30个省市(除西藏及港澳台外)农... 详细信息

党的二十大强调坚持和完善以农业农村为重点的乡村振兴战略,提出加快农业现代化。因此,从生产现代化、经营现代化、可持续发展现代化3个维度构建农业现代化发展水平指标体系,使用熵值法对2013-2021年中国30个省市(除西藏及港澳台外)农业现代化发展水平指数进行测算,并对2013年、2021年中国农业现代化发展水平进行阶段划分与空间格局演化分析,研究影响其指数变化的驱动因素。得出结论:总体上,中国农业现代化发展水平在考察期内有所提高;分维度上,农业生产、经营、可持续发展现代化水平等级基本一致,且均呈空间集聚态势;驱动因素上,经济发展水平、农业生产效率与政府干预度均对中国农业现代化发展有不同程度的积极作用,其中农业生产效率对本地区与邻近地区农业现代化发展均有促进作用。

关键词：农业现代化空间格局演化驱动因素

Strong halo-femoral traction with wide posterior spinal release and three dimensional spinal correction for the treatment of severe adolescent idiopathic scoliosis

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Chinese Medical Journal 2012年第7期125卷 1297-1302页

作者： ZHANG Hong-qi GAO Qi-le GE Lei liu jin-yang GUO Chao-feng liu Shao-hua LU Shi-jin LI jin-song YIN Xin-hua LI Feng Department of Spine Surgery Xiangya Spinal Surgery CenterXiangya Hosptial Affiliated to Central South UniversityChangshaHunan 410008China

Background Many investigators advocate anterior release combined with halo-femoral traction and posterior fusion when treating stiff thoracic curves in patient with adolescent idiopathic scoliosis （AIS）. But the anterior operations often induce severe complications. Some surgeons choose posterior-only surgery with halo-femoral traction, posterior wide release and correction. But to the best of our knowledge, there are only rare prospective studies on these posterior-only surgeries for AIS patients who have a rigid curve more than 80~ and flexibility less than 35%. Methods Sixty-four AIS patients were recruited from September 2006 to June 2009. All patients had rigid curves and underwent spinal correction. They were randomly divided into group A （combined anteroposterior surgery） and group B （posterior-only surgery）. Images and scoliosis research society-22 questionnaire （SRS-22） scores were performed pre- and post-operation and during follow-up visits. The operation time, blood loss, hospital days, and hospital charges were compared between the two groups. Results These patients were followed for an average of 37.5 months （range, 24-65 months）. No serious complications were observed. There were no significant differences between the two groups in gender, age, preoperative radiographic data, or preoperative SRS-22 score. The average operation time, blood loss, hospital days and hospital charges in group B were less than those in group A. The SRS-22 score in group B was better than in group A at post-operation and at final follow-up. Conclusions In AIS with a rigid curve more than 80~ and flexibility less than 35%, strong halo-femoral traction with wide posterior spinal release and three dimensional spinal correction can provide better SRS-22 scores, comparable curve correction, shorter operation time, less blood loss, shorter hospital stays and lower charges when compared to combined anterior and posterior surgery.

关键词： adolescent idiopathic scoliosis posterior spinal release spinal correction

Nearly lattice-defect-free MOF membranes

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Science China Chemistry 2024年第3期67卷 741-743页

作者： Yuzhang Zhu yang liu Jian jin i-Lab Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

Membrane technology has widely accepted as the most energy efficient technology for the separation of ions or molecules. As the core of the membrane technology, the chemical and structure nature of membrane materials determines the application and energy-efficiency of the technology. An advanced membrane that has a remarkable ability to selectively differentiate ions and molecules can significantly enhance the separation technology and revolutionize industrial separation processes.

关键词： processes. separation defect

Regulation of interlayer channels of graphene oxide nanosheets in ultra-thin Pebax mixed-matrix membranes for CO_(2) capture

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Chinese Journal of Chemical Engineering 2024年第3期67卷 257-267页

作者： Feifan yang Yuanhang jin Jiangying liu Haipeng Zhu Rong Xu Fenjuan Xiangli Gongping liu Wanqin jin State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology School of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China Shandong Production and Research Long Membrane Technology Development Co. Ltd.Yantai Economic Development ZoneYantai 265505China

For the application of carbon capture by membrane process,it is crucial to develop a highly permeable CO_(2)-selective *** this work,we reported an ultra-thin polyether-block-amide(Pebax)mixedmatrix membranes(MMMs)incorporated by graphene oxide(GO),in which the interlayer channels were regulated to optimize the CO_(2)/N_(2) separation *** membrane preparation conditions were systematically investigated on the influence of the membrane structure and separation performance,including the lateral size of GO nanosheets,GO loading,thermal reduction temperature,and *** results demonstrated that the precisely regulated interlayer channel of GO nanosheets can rapidly provide CO_(2)-selective transport channels due to the synergetic effects of size sieving and preferential *** GO/Pebax ultra-thin MMMs exhibited CO_(2)/N_(2) selectivity of 72 and CO_(2) permeance of 400 GPU(1 GPU=106 cm^(3)(STP)·cm^(2)·s^(-1)·cmHg^(-1)),providing a promising candidate for CO_(2) capture.

关键词： Mixed-matrix membrane Ultra-thin membrane Pebax Graphene oxide CO_(2) capture

Adaptive Bistable Stochastic Resonance Based Weak Signal Reception in Additive Laplacian Noise

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China Communications 2024年第1期21卷 228-241页

作者： jin liu Zan Li Qiguang Miao Li yang School of Computer Science and Technology Xidian UniversityXi’an 710071China State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China

Weak signal reception is a very important and challenging problem for communication systems especially in the presence of non-Gaussian noise,and in which case the performance of optimal linear correlated receiver degrades *** at this,a novel uncorrelated reception scheme based on adaptive bistable stochastic resonance(ABSR)for a weak signal in additive Laplacian noise is *** analyzing the key issue that the quantitative cooperative resonance matching relationship between the characteristics of the noisy signal and the nonlinear bistable system,an analytical expression of the bistable system parameters is *** this basis,by means of bistable system parameters self-adaptive adjustment,the counterintuitive stochastic resonance(SR)phenomenon can be easily generated at which the random noise is changed into a benefit to assist signal ***,it is demonstrated that approximately 8dB bit error ratio(BER)performance improvement for the ABSR-based uncorrelated receiver when compared with the traditional uncorrelated receiver at low signal to noise ratio(SNR)conditions varying from-30dB to-5dB.

关键词： adaptive bistable stochastic resonance additive Laplacian noise low signal to noise ratio uncorrelated reception scheme weak signal reception

Treatment of Adult Hirschsprung's Disease by Botulinum Toxin A through Anorectal Injection

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Chinese Medical Journal 2018年第24期131卷 3007-3008页

作者： jin-yang liu Zhong-Qing Zheng Ke Zhao Chao Luo Hong-Qiu Han Department of Cardiothoracic Surgery Tianjin Medical University General HospitalTianjin 300052China Department of Gastroenterology Tianjin Medical University General HospitalTianjin 300052China Department of General Surgery Tianjin Medical University General HospitalTianjin 300052China

To the Editor:The patient was a 16-year-old adolescent boy who was diagnosed with congenital *** had difficulty with defecating for more than 10 *** bowel movements stopped more than 1 week *** was admitted to the hospital with incomplete intestinal *** patient showed signs of moderate nutrition,poor mental health,and full abdominal bulging and had an abdominal circumference of 104 cm. Rectal examination showed blasting exhaust and defecation, and the anal pressure measurement value was 89 *** total abdominal augmentation computed tomography and total colorectal sputum angiography showed that the upper and middle rectum,descending colon,transverse colon,and ascending colon were dilated,the maximum diameter of the intestine was 23 cm,and the intestine was filled with feces, suggesting that the lower rectum and sigmoid colon were narrow [Figure 1a and 1b].

关键词： Adult Hirschsprung's Disease Botulinum Toxin Anorectal Injection

Deep insight into the B-cell associated tertiary lymphoid structure and tumor immunotherapy

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Cancer Biology & Medicine 2024年第2期21卷 125-131页

作者： Jilong yang jin Xu Haotian liu Wanyi Xiao Gengpu Zhang Department of Bone and Soft Tissue Tumor Tianjin Medical University Cancer Institute&HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjinTianjin’s Clinical Research Center for CancerKey Laboratory of Molecular Cancer EpidemiologyTianjin 300060China Department of Anaesthesiology Tianjin University Tianjin HospitalTianjin 300211China

Bod et al.1 recently published a study in Nature that garnered attention to B cell-associated anti-tumor immunity and immunotherapy of melanoma and other *** a promising supplemental immunotherapy to mainstream method... 详细信息

关键词： immunotherapy immunity

Synthesizing active and durable cubic ceria catalysts(<6 nm)for fast dehydrogenation of bio-polyols to carboxylic acids coproducing green H_(2)

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Green Energy & Environment 2024年第3期9卷 529-543页

作者： Mengyuan liu Puhua Sun Guangyu Zhang Xin jin Chaohe yang Honghong Shan State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringChina University of PetroleumNo.66 Changjiang West RoadQingdaoShandong266580China SINOPEC Research Institute of Safety Engineering Co. Ltd.No.339 Songling RoadQingdaoShandong266000China

Dehydrogenation is considered as one of the most important industrial applications for renewable *** ceria-based catalysts are known to display promising dehydrogenation performances in this *** particle size(>20 nm)and less surface defects,however,hinder further application of ceria ***,an alternative strategy involving lactic acid(LA)assisted hydrothermal method was developed to synthesize active,selective and durable cubic ceria of<6 nm for dehydrogenation *** studies of growth mechanism revealed that,the carboxyl and hydroxyl groups in LA molecule synergistically manipulate the morphological evolution of ceria *** groups determine the cubic shape and particle size,while hydroxyl groups promote compositional transformation of ceria precursors into CeO_(2) ***,enhanced oxygen vacancies(Vo)on the surface of CeO_(2) were obtained owing to continuous removal of O species under reductive *** CeO_(2) catalysts synthesized by the LA-assisted method,immobilized with bimetallic PtCo clusters,exhibit a record high activity(TOF:29,241 h^(-1))and Vo-dependent synergism for dehydrogenation of bio-derived polyols at 200℃.We also found that quenching Vo defects at air atmosphere causes activity loss of PtCo/CeO_(2) *** regenerate Vo defects,a simple strategy was developed by irradiating deactivated catalysts using hernia *** outcome of this work will provide new insights into manufacturing durable catalyst materials for aqueous phase dehydrogenation applications.

关键词： Cubic ceria Oxygen vacancy Dehydrogenation C-H bond activation