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Numerical simulation of non-Darcian flow through a porous medium

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Particuology 2009年第3期7卷 193-198页

作者： Duoxing yang Yipeng yang V.A.F. Costa Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Crustul Dynamics Chinese Earthquake Administration Beijing 100085 China Ministry of Environmentul Protection of the People's Republic of China. Beijing 100035 China Departamento de Engenharia Mecenica. Universidade de Aveiro Campus Universiterio de Santiago 3810-193 Aveiro Portugal

This work reports on fluid flow in a fluid-saturated porous medium, accounting for the boundary and inertial effects in the momentum equation. The flow is simulated by Brinkman-Forchheimer-extended Darcy formulation （DFB）, using MAC （Marker And Cell） and Chorin pressure iteration method. The method is validated by comparison with analytic results. The effect of Reynolds number, Darcy number, porosity and viscosity ratio on velocity is investigated. As a result, it is found that Darcy number has a decisive influence on pressure as well as velocity, and the effect of viscosity ratio on velocity is very strong given the Darcy number. Additional key findings include unreasonable choice of effective viscosity can involve loss of important physical information.

关键词： MAC Pressure Darcy law Porous media Permeability Viscosity ratio

A ferric citrate derived Fe-N-C electrocatalyst with stepwise pyrolysis for highly efficient oxygen reduction reaction

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Chinese Chemical Letters 2022年第1期33卷 362-367页

作者： Min Zhang Bolong yang Ting yang Yahui yang Zhonghua Xiang State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China College of Chemistry and Chemical Engineering Hunan Normal UniversityChangsha 410081China

Unremitting and intensive researches about efficient non-precious metal electrocatalysts are necessary for large-scale commercial applications of fuel cells,while iron and nitrogen co-doped carbon(Fe-N-C)materials has become one of the most promising electrocatalysts to replace Pt-based noble metal ***,the traditional Fe-doped ZIF with rhomb dodecahedron morphology limits the exposure of active sites and the utilization of atoms,even affecting the performance of the ***,a Fe/N co-doped catalyst with a flower-like morphology was prepared using ferric citrate source along with secondary NH_(3)heat *** optimal catalyst(termed as 4Fe_(citrate)-N-C-3)showed distinguished oxygen reduction reaction(ORR)activity with a half-wave potential of 0.8 and 0.9 V(***)in acid and alkaline media,*** addition,4Fe_(citrate)-N-C-3 maintained more than 80%of original activity even after 50,000 s which is superior to the benchmark Pt/*** strategy of controlling morphology and composition is meaningful for the optimization of non-precious metal electrocatalysts for ORR in fuel cells or metal-air batteries.

关键词： Oxygen reduction reaction Non-precious metal electrocatalysts Fuel cell ZIF-8 NH3 activation

MAGNETIC RESONANCE IMAGING CHARACTERISTICS AND SURGICAL RESULTS OF ADRENOCORTICOTROPIN-SECRETING PITUITARY ADENOMAS

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Chinese Medical Sciences Journal 2008年第1期23卷 44-48页

作者： Bing xing Kan Deng Zu-yuan Ren Chang-bao Su Ren-zhi Wang Yi yang Wen-bin Ma Yong-ning Li Department of Neurosurgery Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730

Objective To evaluate magnetic resonance imaging （MRI） characteristics and surgical results of adrenocorticotropin （ACTH） -secreting pituitary adenomas. Methods MRI characteristics and relationship between MRI positive rate and surgical results of 266 patients with pathologically confn＇med Cushing＇s disease were analyzed retrospectively. All patients underwent thin-section sagittal and coronal scans of the pituitary gland before and after administration of gadolinium-diethylene triamine pentaacetic acid （Gd-DTPA） on a 1. 5 Tesla MR/scanner, and dynamic enhanced MR/was performed in 39 patients. All patients underwent transsphenoidal adenomectomy. Endocrinological examinations and assessments were performed. Results Preoperative MR/revealed normal results in 41 （ 15.4% ） cases, microadenoma in 179 （67. 3% ）, macroadenoma in 42 （ 15.8% ）, and huge adenoma in 4 （ 1.5% ）. Pituitary apoplexy was found in 13 （4.9%） cases. Positive rate of ACTH-secreting adenomas was 84.6% （225/266） on MR/scans, and that of small microadenomas was 87.2% （34/39） on dynamic enhanced MRI scans. Preoperative endocrinological tests of 199 cases supported the diagnosis of typical Cushing＇s disease, while the other 67 cases had atypical endocrinological results. The endocrinological cure rate, remission rate, and inefficacy rate were 85.7%, 7.9%, and 6. 4%, respectively. There was no difference in the initial endocrinological cure rate between the patients with positive and normal MRI results （90% vs. 87. 8%, P =0. 904）. Conclusions Enhanced coronal pituitary MR/ is helpful for preoperative localization of ACTH-secreting pituitary microadenoma. Dynamic enhanced MR/may improve detection rate of microadenoma. There is no marked difference in the surgical results for patients with preoperative MR/results indicating presence or absence of microadenoma.

关键词： adrenocorticotropin-secreting pituitary adenoma magnetic resonance imaging diagnosis treatment

Different frequencies of repetitive transcranial magnetic stimulation combined with local injection of botulinum toxin type A for post-stroke lower limb spasticity:study protocol for a prospective,single-center,non-randomized,controlled clinical trial

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Neural Regeneration Research 2022年第11期17卷 2491-2496页

作者： yang Shao yang yang Yong-Xin Sun Ai-Hua Xu Department of Rehabilitation Medicine the First Affiliated Hospital of China Medical UniversityShenyangLiaoning ProvinceChina

No definite consensus has currently been reached regarding the safety and efficacy of low-or high-frequency repetitive transcranial magnetic stimulation in the treatment of post-stroke muscle *** latest research indicates that when combined with local injections of botulinum toxin type A,it is more effective on post-stroke muscle spasticity than local injections of botulinum toxin type A *** designed a prospective,single-center,non-randomized,controlled clinical trial to investigate the safety and effica cy of different frequencies of repetitive transcranial magnetic stimulation combined with local injections of botulinum toxin type A in treating post-stroke lower limb muscle spasticity to determine an optimal therapeutic *** trial will enroll 150 patients with post-stroke muscle spasticity admitted to the Department of Rehabilitation Medicine at the First Affiliated Hos pital of China Medical Unive *** enrolled patients will undergo ro utine rehabilitation training and will be divided into five groups in-30 per group) according to the particular area of cerebral infa rction and treatment methods.G roup A:Patients with massive cerebral infarction will be given local injections of botulinum toxin type A and low-frequency(1 Hz)repetitive transcranial magnetic stimulation on the contralate ral side;G roup B:Patients with non-massive cerebral infarction will be given local injections of botulinum toxin type A and high-frequency(10-20 Hz) re petitive transcranial magnetic stimulation on the affected side;G roup C:Patients with massive/non-massive cerebral infarction will be given local injections of botulinum toxin type A;G roup D:Patients with massive cerebral infarction will be given low-frequency(1 Hz) repetitive transcranial magnetic stimulation on the contralate ral side;and G roup E:Patients with non-massive cerebral infa rction will be given high-frequency(10-20 Hz) repetitive transcranial magnetic stimulation on the affected ***

关键词： Botulinum toxin type A exercise lower limbs muscle spasticity neural regeneration rehabilitation training repetitive transcranial magnetic stimulation stroke

The cotton mitochondrial chimeric gene orf610a causes male sterility by disturbing the dynamic balance of ATP synthesis and ROS burst

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The Crop Journal 2022年第6期10卷 1683-1694页

作者： Yongjie Zhang yang Han Meng Zhang Xuexian Zhang Liping Guo Tingxiang Qi Yongqi Li Juanjuan Feng Hailin Wang Huini Tang Xiuqin Qiao Liangliang Chen Xiatong Song Chaozhu xing Jianyong Wu Zhengzhou Research Base State Key Laboratory of Cotton BiologySchool of Agricultural SciencesZhengzhou UniversityZhengzhou 450001HenanChina State Key Laboratory of Cotton Biology/Key Laboratory for Cotton Genetic Improvement Ministry of AgricultureInstitute of Cotton Research of Chinese Academy of Agricultural SciencesAnyang 455000HenanChina State Key Laboratory of Cotton Biology(Hebei Base) College of AgronomyHebei Agricultural UniversityBaoding 071001HebeiChina

Plant cytoplasmic male sterility(CMS)is maternally inherited and often manifested as aborted pollen development,but the molecular basis of abortion remains to be *** facilitate an investigation of CMS in cotton,the complete sequence of cotton mitochondrial(mt)genome for CMS-D2 line ZBA was *** mt genome was assembled as a single circular molecule with 634,036 bp in length.A total of 194 ORFs,36 protein-coding genes,six r RNAs,and 24 t RNAs were *** chimeric genes encoding hypothetical proteins with transmembrane domains were *** them,a previously unknown chimeric gene,orf610a,which is composed of atp1 and a 485-bp downstream sequence of unknown nature,was ***-PCR and q RT-PCR validation indicated that orf610a was expressed specifically in a sterile *** expression of orf610a in yeast resulted in excessive accumulation of reactive oxygen species and reduction in ATP content,in addition to inhibition of cellular *** *** overexpressing orf610a fused with a mitochondrial targeting peptide displayed partial male *** between ORF610a and the nuclear-encoded protein RD22 indicated an association between ORF610a and pollen *** feedback during transcriptional regulation between nuclear regulatory factors and the mt CMS gene may account for the male sterility of ZBA.

关键词： Cytoplasmic male sterility Mitochondrial genome Chimeric gene Reactive oxygen species ATP

Adaptive detector design of MIMO radar with unknown covariance matrix

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Journal of Systems Engineering and Electronics 2010年第6期21卷 954-960页

作者： Lingjiang Kong Guolong Cui Xiaobo yang Jianyu yang School of Electronic Engineering University of Electronic Science and Technology of China Chengdu 611731 P. R. China

The problem of detecting signal with multiple input mul-tiple output （MIMO） radar in correlated Gaussian clutter dominated scenario with unknown covariance matrix is dealt with. The gen-eral MIMO model, with widely separated sub-arrays and co-located antennas at each sub-array, is adopted. Firstly, the generalized likelihood ratio test （GLRT） with known covariance matrix is ob-tained, and then the Rao and Wald detectors are devised, which have proved that the Rao and Wald test coincide with GLRT detec-tor. To make the detectors fully adaptive, the secondary data with signal-free will be collected to estimate the covariance. The per-formance of the proposed detector is analyzed, however, it is just ancillary. A thorough performance assessment by several numer-ical examples is also given, which has considered the sense with co-located antennas configure of transmitters and receivers array. The results show that the performance the proposed adaptive de-tector is better than LJ-GLRT, and the loss can be acceptable in comparison to their non-adaptive counterparts.

关键词： MIMO radar generalized likelihood ratio test Rao and Wald tests correlated Gaussian clutter fully adaptive.

Livelihood Vulnerability and Adaptation for Households Engaged in Forestry in Ecological Restoration Areas of the Chinese Loess Plateau

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Chinese Geographical Science 2024年第5期34卷 849-868页

作者： yang Qingqing CHEN yang LI Xiaomin yang Jie GAO Yanhui Northwest Land and Resources Research Center Global Regional and Urban Research InstituteShaanxi Normal UniversityXi’an 710119China School of Geographical Science and Tourism Shaanxi Normal UniversityXi’an 710119China School of Tourism and Research Institute of Human Geography Xi’an International Studies UniversityXi’an 710128China

Chinese Loess Plateau has achieved a win-win situation concerning ecological restoration and socio-economic ***,synergistic development may not be realized at the local *** areas undergoing ecological restoration,livelihood vulner-ability may be more pronounced due to the inflexibility,policy protection,and susceptibility to climate and market changes in forestry *** this issue has attracted academic interest,empirical studies are relatively *** study,centered on Jiaxian County,Shaanxi Province of China explored the households’livelihood vulnerability and coping strategies and group heterogeneity con-cerned with livelihood structures or forestry resources through field investigation,comprehensive index assessment,and nonparametric *** showed that:1)the percentage of households with high livelihood vulnerability indicator(LVI)(>0.491)reached 46.34%.2)Eight groups in livelihood structures formed by forestry,traditional agriculture,and non-farm activities were significantly different in LVI,land resources(LR),social networks(SN),livelihood strategies(LS),housing characteristics(HC),and socio-demo-graphic profile(SDP).3)The livelihood vulnerability of the groups with highly engaged/reliance on jujube(Ziziphus jujuba)forest demonstrated more prominent livelihood vulnerability due to the increased precipitation and cold market,where the low-engaged with reliance type were significantly more vulnerable in LVI,SDP,LR,and HC.4)The threshold of behavioral triggers widely varied,and farmers dependent on forestry livelihoods showed negative coping ***,the cutting behavior was strongly associated with lagged years and government subsidies,guidance,and high returns of ***,the findings can provide guidance on the dir-ection of livelihood vulnerability mitigation and adaptive government management in ecologically restored *** issue of farmers’livelihood sustainability in the context of ecologi

关键词： livelihood vulnerability forestry coping behaviors climate change market change Jiaxian County

A high-throughput strategy for rapid synthesis and characterization of Ni-based superalloys

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Rare Metals 2022年第8期41卷 2693-2700页

作者： Lei Zhao Su-Ran Liu Liang Jiang Li-Xia yang Li-long Zhu Hui Wang Wen-Yu Zhang Zai-Wang Huang Yuan-Bin Deng Christoph Broeckmann Hai-Liang Huang Hai-Zhou Wang Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Metal Materials CharacterizationCentral Iron and Steel Research InstituteBeijing100081China National Center for Materials Service Safety University of Science and Technology BeijingBeijing100083China Institute for Advanced Studies in Precision Materials Yantai UniversityYantai264005China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China Institute for Materials Applications in Mechanical Engineering RWTH Aachen UniversityAachen52062Germany

This study developed a new high-throughput strategy,designated as hot-isostatic-pres sing-based microsynthesis approach(HIP-MSA),to optimize high-performance nickel-based superalloys in a rapid,efficient,and cost-effective manner.A specific honeycomb-array structure containing 106 discrete cells was designed and optimized using finite element analysis(FEA)and then applied to create a combinatorial library consisting of 106 Ni-based superalloys with various Co,Nb and Ta *** integration with high-throughput characterization tools,extensive composition and phase structure data were collected quickly and *** the superalloys with higher amounts of Nb and Ta,the detrimentalηphase displaying needle-like morphology was observed,and its content(wt%)increased drastically with Ta and Nb contents ***,the increase of Co addition in those alloys was confirmed to be surprisingly beneficial by significantly suppressing the formation ofηphase that was induced by high Nb and Ta *** zero-phasefraction(ZPF)line ofηphase was established,which is critical to design superalloy chemistry for superior micros tructural stability at high-temperature service conditions.

关键词： Bulk combinatorial synthesis Honeycombarray structure Finite element analysis(FEA) Superalloy Zero-phase-fraction(ZPF)line

Effect of Comprehensive Therapy based on Chinese Medicine Patterns on Self-Efficacy and Effectiveness Satisfaction in Chronic Obstructive Pulmonary Disease Patients

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Chinese Journal of Integrative Medicine 2019年第10期25卷 736-742页

作者： YU Xue-qing WANG Ming-hang LI Jian-sheng LI Su-yun XIE yang BAI Yun-ping ZHANG Hai-long CAO Fan HOU Cong-xia MA Li-jun Department of Respiratory the First Affiliated Hospital of Henan University of Chinese Medicine Zhengzhou (450000) China Collaborative Innovation Center for Respiratory Disease Diagnosis and Treatment & Chinese Medicine Development of Henan Province Henan University of Chinese Medicine Zhengzhou (450046) China Henan Key Laboratory of Chinese Medicine for Respiratory Disease Henan University of Chinese Medicine Zhengzhou (450046) China Departm ent of Respiratory Henan Provincial People's Hospital Zhengzhou (450003) China

Objective: To evaluate the effect of comprehensive therapy based on Chinese medicine(CM) patterns on self-efficacy and satisfaction with its effectiveness in patients with chronic obstructive pulmonary disease(COPD). Methods: A total of 216 patients were randomly divided into the trial group(n=108) and the control group(n=108) based on the stratified and block randomization design. Patients in the trial group were treated with conventional Western medicine combined with Bufei Jianpi Granules(补肺健脾颗粒), Bufei Yishen Granules(补肺益肾颗粒), and Yiqi Zishen Granules(益气滋肾颗粒) according to the CM patterns respectively, and patients in the control group were treated with conventional Western medicine. The COPD Self-Efficacy Scale(CSES) and the Effectiveness Satisfaction Questionnaire for COPD(ESQ-COPD) were employed in a 6-month treatment and in further 6 month follow-up visit. Results: Among the 216 patients, 191 patients(97 in the trial group and 94 in the control group) fully completed the study. After 12-month treatment and follow-up, the mean scores of the trial group all continued to increase over time, which were significantly higher than those of the control group(P<0.05), and the improvement in the following trial group domain: negative affect domain(12.13%), intense emotional arousal domain(12.21%), physical exertion domain(11.72%), weather/environmental domain(13.77%), behavioral risk domain(7.67%) and total score(10.65%). The trial group also exhibited significantly higher mean scores in the ESQ-COPD(P<0.05) and the improvement in the following domain: capacity for life and work domain(30.59%), clinical symptoms domain(53.52%), effect of therapy domain(35.95%), convenience of therapy domain(35.54%), and whole effect domain(52.47%). Conclusions: Bufei Jianpi Granules, Bufei Yishen Granules and Yiqi Zishen Granules can improve the self-efficacy and satisfaction of COPD patients.

关键词： chronic obstructive pulmonary disease Chinese medicine self efficacy effectiveness satisfaction