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Shuganheweitang Ameliorates Chronic Unpredictable Mild Stress-Induced Depression-Like Behaviors in Rats through the PI3K/AKT/mTOR Pathway: Involvement of Amino Acids, Glycerophospholipids, and Energy Metabolism
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作者 Qi Li Junjie Hu +9 位作者 Zhenpeng Qiu Juan Li Misi Zhou Xiao Huang di he Chuanyu Yuan Kang Yin Yanwen Liu Songlin Liu Xin Chen 《Chinese Medicine》 CAS 2023年第1期13-55,共43页
Background: Depression is a typical psychosomatic disease. Shuganheweitang (SGHWT) is a clinical formula that effectively treats depression. However, the potential mechanism used by SGHWT to ameliorate depression-like... Background: Depression is a typical psychosomatic disease. Shuganheweitang (SGHWT) is a clinical formula that effectively treats depression. However, the potential mechanism used by SGHWT to ameliorate depression-like behaviors is still unclear. This study investigated the effects of SGHWT on metabolic change in the liver and hypothalamus with signaling pathways involved in chronic unpredictable mild stress (CUMS)-induced depression in rats to explore the mechanism of the anti-depressive effect. Methods: A total of 52 rats were used to create a model of depression by CUMS combined with solitary rearing for 6 weeks. Open field test (OFT), sucrose preference test (SPT), forced swim test (FST), and body weight (BW) were performed to analyze the pharmacodynamic effects of SGHWT. H&E staining, Nissl staining, immunofluorescence, immunohistochemistry, and western blot were used to evaluate the mechanism of action. Untargeted metabolomics techniques by ultra-performance liquid chromatography-quantitative time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS) were used to analyze all the metabolic differences in the liver and hypothalamus. Results: SGHWT improved CUMS-induced depression-like behaviors in vivo. SGHWT reduced hepatic c-Fos protein expression and increased hypothalamic c-Fos protein expression. Moreover, p-PI3K, p-AKT473, p-AKT308, and p-mTOR protein expressions were significantly downregulated in the liver and hypothalamus of CUMS rats. Notably, these alterations were reversed by the SGHWT administration. Furthermore, the metabolomic analysis identified 15 and 5 key differential SPT-associated metabolites in the liver and hypothalamus, respectively. Conclusion: This study suggests that SGHWT ameliorates chronic unpredictable mild stress-induced depression-like behaviors, by the involvement of amino acids, glycerophospholipids, energy metabolism, and the PI3K/AKT/mTOR pathway. Highlights: 1) Shuganheweitang was derived from the TCM herbal formula Sinisan. 2) SGHWT treatment reverses depression-like behaviors in CUMS-induced rats. 3) The mechanism of SGHWT on depression by the liver and hypothalamus metabolomics. 4) SGHWT regulates amino acids, glycerophospholipids, and energy metabolism. 5) SGHWT exerts antidepressant effects through the PI3K/AKT/mTOR pathway. 展开更多
关键词 Shuganheweitang Chronic Unpredictable Mild Stress DEPRESSION Metabolomics PI3K/AKT/MTOR
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Pore structure of low‑permeability coal and its deformation characteristics during the adsorption–desorption of CH4/N2
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作者 Pengfei Ji Haifei Lin +5 位作者 Xiangguo Kong Shugang Li Biao Hu Pei Wang di he Songrui Yang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第4期107-127,共21页
The pore structure of coal plays a key role in controlling the storage and migration of CH4/N2.The pore structure of coal is an important indicator to measure the gas extraction capability and the gas displacement efe... The pore structure of coal plays a key role in controlling the storage and migration of CH4/N2.The pore structure of coal is an important indicator to measure the gas extraction capability and the gas displacement efect of N2 injection.The deformation characteristic of coal during adsorption–desorption of CH4/N2 is an important factor afecting CH4 pumpability and N2 injectability.The pore structure characteristics of low-permeability coal were obtained by fuid intrusion method and photoelectric radiation technology.The multistage and connectivity of coal pores were analyzed.Subsequently,a simultaneous test experiment of CH4/N2 adsorption–desorption and coal deformation was carried out.The deformation characteristics of coal were clarifed and a coal strain model was constructed.Finally,the applicability of low-permeability coal to N2 injection for CH4 displacement technology was investigated.The results show that the micropores and transition pores of coal samples are relatively developed.The pore morphology of coal is dominated by semi-open pores.The pore structure of coal is highly complex and heterogeneous.Transition pores,mesopores and macropores of coal have good connectivity,while micropores have poor connectivity.Under constant triaxial stress,the adsorption capacity of the coal for CH4 is greater than that for N2,and the deformation capacity of the coal for CH4 adsorption is greater than that for N2 adsorption.The axial strain,circumferential strain,and volumetric strain during the entire process of CH4 and N2 adsorption/desorption in the coal can be divided into three stages.Coal adsorption–desorption deformation has the characteristics of anisotropy and gas-diference.A strain model for the adsorption–desorption of CH4/N2 from coal was established by considering the expansion stress of adsorbed gas on the coal matrix,the compression stress of free gas on the coal matrix,and the expansion stress of free gas on micropore fractures.N2 has good injectability in low-permeability coal seams and has the dual functions of improving coal seam permeability and enhancing gas fow,which can signifcantly improve the efectiveness of low-permeability coal seam gas control and promote the efcient utilization of gas resources. 展开更多
关键词 Low-permeability coal Pore structure Adsorption–desorption Deformation characteristics Strain model
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Combining field data and modeling to better understand maize growth response to phosphorus(P) fertilizer application and soil P dynamics in calcareous soils
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作者 Weina Zhang Zhigan Zhao +3 位作者 di he Junhe Liu Haigang Li Enli Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期1006-1021,共16页
We used field experimental data to evaluate the ability of the agricultural production system model (APSIM) to simulate soil P availability,maize biomass and grain yield in response to P fertilizer applications on a f... We used field experimental data to evaluate the ability of the agricultural production system model (APSIM) to simulate soil P availability,maize biomass and grain yield in response to P fertilizer applications on a fluvo-aquic soil in the North China Plain.Crop and soil data from a 2-year experiment with three P fertilizer application rates(0,75 and 300 kg P_(2)O_(5) ha^(–1)) were used to calibrate the model.Sensitivity analysis was carried out to investigate the influence of APSIM SoilP parameters on the simulated P availability in soil and maize growth.Crop and soil P parameters were then derived by matching or relating the simulation results to observed crop biomass,yield,P uptake and Olsen-P in soil.The re-parameterized model was further validated against 2 years of independent data at the same sites.The re-parameterized model enabled good simulation of the maize leaf area index (LAI),biomass,grain yield,P uptake,and grain P content in response to different levels of P additions against both the calibration and validation datasets.Our results showed that APSIM needs to be re-parameterized for simulation of maize LAI dynamics through modification of leaf size curve and a reduction in the rate of leaf senescence for modern staygreen maize cultivars in China.The P concentration limits (maximum and minimum P concentrations in organs)at different stages also need to be adjusted.Our results further showed a curvilinear relationship between the measured Olsen-P concentration and simulated labile P content,which could facilitate the initialization of APSIM P pools in the NCP with Olsen-P measurements in future studies.It remains difficult to parameterize the APSIM SoilP module due to the conceptual nature of the pools and simplified conceptualization of key P transformation processes.A fundamental understanding still needs to be developed for modelling and predicting the fate of applied P fertilizers in soils with contrasting physical and chemical characteristics. 展开更多
关键词 MAIZE phosphorus availability modeling APSIM maize APSIM SoilP
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Dysregulated N6-methyladenosine modification in peripheral immune cells contributes to the pathogenesis of amyotrophic lateral sclerosis
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作者 di he Xunzhe Yang +5 位作者 Liyang Liu Dongchao Shen Qing Liu Mingsheng Liu Xue Zhang Liying Cui 《Frontiers of Medicine》 SCIE CSCD 2024年第2期285-302,共18页
Amyotrophic lateral sclerosis(ALS)is a progressive neurogenerative disorder with uncertain origins.Emerging evidence implicates N6-methyladenosine(m6A)modification in ALS pathogenesis.Methylated RNA immunoprecipitatio... Amyotrophic lateral sclerosis(ALS)is a progressive neurogenerative disorder with uncertain origins.Emerging evidence implicates N6-methyladenosine(m6A)modification in ALS pathogenesis.Methylated RNA immunoprecipitation sequencing(MeRIP-seq)and liquid chromatography–mass spectrometry were utilized for m6A profiling in peripheral immune cells and serum proteome analysis,respectively,in patients with ALS(n=16)and controls(n=6).The single-cell transcriptomic dataset(GSE174332)of primary motor cortex was further analyzed to illuminate the biological implications of differentially methylated genes and cell communication changes.Analysis of peripheral immune cells revealed extensive RNA hypermethylation,highlighting candidate genes with differential m6A modification and expression,including C-X3-C motif chemokine receptor 1(CX3CR1).In RAW264.7 macrophages,disrupted CX3CR1 signaling affected chemotaxis,potentially influencing immune cell migration in ALS.Serum proteome analysis demonstrated the role of dysregulated immune cell migration in ALS.Cell type-specific expression variations of these genes in the central nervous system(CNS),particularly microglia,were observed.Intercellular communication between neurons and glial cells was selectively altered in ALS CNS.This integrated approach underscores m6A dysregulation in immune cells as a potential ALS contributor. 展开更多
关键词 amyotrophic lateral sclerosis N^(6)-methyladenosine epi-transcriptome PROTEOME single cell RNA sequencing analysis CX3CR1
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Risk Factors and Distribution of Pathogens for Pulmonary Infection in Patients with Severe Acute Pancreatitis
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作者 Quanshui Peng Peng Chen di he 《Journal of Advances in Medicine Science》 2021年第1期39-43,共5页
Objective:To investigate risk factors and distribution of pathogens for pulmonary infection in patients with severe acute pancreatitis.Methods:The clinical data of 285 patients with severe acute pancreatitis were retr... Objective:To investigate risk factors and distribution of pathogens for pulmonary infection in patients with severe acute pancreatitis.Methods:The clinical data of 285 patients with severe acute pancreatitis were retrospectively analyzed.Sputum specimens of patients with lung infections were studied.Univariate analysis and logistic regression were performed to screening the factors correlating to lung infections.Results:Gram-negative bacilli were the principal microorganisms isolated from those lung infections,and these bacterial pathogens demonstrated a marked pattern of antibiotic resistance.It was identified that age(OR 1.05,95%CI 1.01-1.09,p=0.01),Ranson scores(OR 3.01,95%CI 1.13-8.03,p=0.03)and surgical treatment(OR4.27,95%CI 1.03-17.65,p=0.04)were independent risk factors of lung infections in patients with severe acute pancreatitis.Conclusion:Analysis of pathogen spectrum and drug sensitivity will contribute to choosing antibiotics empirically.And preventive measures aimed at risk factors could help reduce the incidence of lung infections in patients with severe acute pancreatitis. 展开更多
关键词 Pulmonary infections Severe acute pancreatitis Risk factors Distribution of pathogens
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The response of structure and nitrogen removal function of the biofilm on submerged macrophytes to high ammonium in constructed wetlands
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作者 Xue Jiang Mengmeng Wang +3 位作者 Shunqing Yang di he Fei Fang Liuyan Yang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第8期129-141,共13页
The ammonium exceedance discharge from sewage treatment plants has a great risk to the stable operation of subsequent constructed wetlands(CWs).The effects of high ammonium shocks on submerged macrophytes and epiphyti... The ammonium exceedance discharge from sewage treatment plants has a great risk to the stable operation of subsequent constructed wetlands(CWs).The effects of high ammonium shocks on submerged macrophytes and epiphytic biofilms on the leaves of submerged macrophytes in CWs were rarely mentioned in previous studies.In this paper,the 16S rRNA sequencing method was used to investigate the variation of the microbial communities in biofilms on the leaves of Vallisneria natans plants while the growth characteristics of V.natans plants were measured at different initial ammonium concentrations.The results demonstrated that the total chlorophyll and soluble sugar synthesis of V.natans plants decreased by 51.45%and 57.16%,respectively,and malondialdehyde content increased threefold after8 days if the initial NH_(4)^(+)-N concentration was more than 5 mg/L.Algal density,bacterial quantity,dissolved oxygen,and pH increased with high ammonium shocks.The average removal efficiencies of total nitrogen and NH_(4)^(+)-N reached 73.26%and 83.94%,respectively.The heat map and relative abundance analysis represented that the relative abundances of phyla Proteobacteria,Cyanobacteria,and Bacteroidetes increased.The numbers of autotrophic nitrifiers and heterotrophic nitrification aerobic denitrification(HNAD)bacteria expanded in biofilms.In particular,HNAD bacteria of Flavobacterium,Hydrogenophaga,Acidovorax,Acinetobacter,Pseudomonas,Aeromonas,and Azospira had higher abundances than autotrophic nitrifiers because there were organic matters secreted from declining leaves of V.natans plants.The analysis of the nitrogen metabolic pathway showed aerobic denitrification was the main nitrogen removal pathway.Thus,the nitrification and denitrification bacterial communities increased in epiphytic biofilms on submerged macrophytes in constructed wetlands while submerged macrophytes declined under ammonium shock loading. 展开更多
关键词 Ammonium shock loading BIOFILM Autotrophic nitrifiers Heterotrophic nitrification aerobic denitrification bacteria Submerged macrophyte
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一种岩溶地下水污染风险的源径标值评价方法 被引量:6
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作者 刘长礼 王秀艳 +4 位作者 赵悦文 王帅伟 李宏钊 邸贺 孙伟超 《地球学报》 EI CAS CSCD 北大核心 2021年第3期363-372,共10页
以往,国内外提出的关于岩溶地下水污染风险评价方法与防控措施,都是基于地下水脆弱性评价的理论方法,是在对岩溶地区进行流域范围内大面积的脆弱性评价基础上,进行岩溶水污染危险性分区,然后以危险性分区为依据,提出岩溶水污染风险防控... 以往,国内外提出的关于岩溶地下水污染风险评价方法与防控措施,都是基于地下水脆弱性评价的理论方法,是在对岩溶地区进行流域范围内大面积的脆弱性评价基础上,进行岩溶水污染危险性分区,然后以危险性分区为依据,提出岩溶水污染风险防控措施。这种风险评价与防控方法,是针对大区域大范围的岩溶水的。评价出的结果或提出的防控措施,对于具体的岩溶水源地针对性差。本文针对中国南方岩溶地区降雨时期集中、水循环快、分布不均、易受污染等特点,综合考虑水源地(污染目标)、污染源、污染途径、污染造成的损失值等因素,首次提出了岩溶水污染风险的“源-径-标-值”(SPTV)评价方法,从控制污染源、切断污染途径、保护岩溶水源等角度提出污染防控措施,针对性、可操作性都很强,克服了已有方法的缺点,具有较好的推广应用前景。 展开更多
关键词 源-径-标-值 岩溶地区 地下水污染 风险评价
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肝纤维化病因与机制研究进展 被引量:11
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作者 何迪 陈鹏 +3 位作者 刘锋 徐杨 韩磊 丁文静 《昆明医科大学学报》 CAS 2022年第11期165-171,共7页
肝纤维化(hepatic fibrosis,HF)是由遗传相关疾病、慢性病毒性肝炎、酒精性肝炎、胆汁淤积和药物性肝损伤等多种慢性肝病引起的过度修复反应产生多种细胞外基质(extracellular matrix,ECM)的异常沉积的结果。肝纤维化的发生发展机制和... 肝纤维化(hepatic fibrosis,HF)是由遗传相关疾病、慢性病毒性肝炎、酒精性肝炎、胆汁淤积和药物性肝损伤等多种慢性肝病引起的过度修复反应产生多种细胞外基质(extracellular matrix,ECM)的异常沉积的结果。肝纤维化的发生发展机制和肝星状细胞(hepatic stellate cells,HSC)、肝巨噬细胞、内质网应激(endoplasmic reticulum stress,ERs)和自噬等有关。肝脏的纤维化是一个动态发展过程,在没有干预的情况下会继续发展成为肝硬化,甚至发展为肝细胞癌。因此,延缓或者逆转肝纤维化的发生具有非常重要的临床意义。对肝纤维化病因和发生发展机制总结,为抗肝纤维化的药物研究提供参考。 展开更多
关键词 肝纤维化 病因 肝星状细胞 内质网应激
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WSR三元定位视角下突发公共事件的政府多主体信息协同机制研究 被引量:19
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作者 狄鹤 张海涛 张连峰 《情报杂志》 CSSCI 北大核心 2021年第7期189-194,188,共7页
[目的/意义]面对突发公共事件,政府各职能部门如何快速、准确、协调处理海量信息已成为大数据智慧应急管理的关键环节。政府多主体间信息协同的质量直接影响应急信息工作水平,需要针对性的研究。[方法/过程]在WSR系统方法论的框架下,结... [目的/意义]面对突发公共事件,政府各职能部门如何快速、准确、协调处理海量信息已成为大数据智慧应急管理的关键环节。政府多主体间信息协同的质量直接影响应急信息工作水平,需要针对性的研究。[方法/过程]在WSR系统方法论的框架下,结合2020年中国南方洪涝灾害案例,对应急信息协同机制进行物理——事理——人理三元系统定位,通过逻辑推演,构建突发公共事件的政府多主体信息协同机制。[结果/结论]基于集成思维,描述WSR系统方法论在突发公共事件响应中的应用路径,分析政府多主体间协同治理和信息联动的内在机理。为突发公共事件政府多主体信息机制的运用和协同机制的建立提供有针对性的治理架构及启示性参考依据。 展开更多
关键词 突发公共事件 政府多主体 信息协同 应急管理 WSR系统方法论
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The Gold Coast criteria increases the diagnostic sensitivity for amyotrophic lateral sclerosis in a Chinese population 被引量:1
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作者 Dongchao Shen Xunzhe Yang +6 位作者 Yanying Wang di he Xiaohan Sun Zhengyi Cai Jinyue Li Mingsheng Liu Liying Cui 《Translational Neurodegeneration》 SCIE CAS 2021年第3期359-366,共8页
Objectives:The aim of this study was to assess and compare the diagnostic utility of a new diagnostic criteria for amyotrophic lateral sclerosis(ALS),abbreviated as the‘Gold Coast Criteria’,with the revised El Escor... Objectives:The aim of this study was to assess and compare the diagnostic utility of a new diagnostic criteria for amyotrophic lateral sclerosis(ALS),abbreviated as the‘Gold Coast Criteria’,with the revised El Escorial(rEEC)and Awaji criteria.Methods:Clinical and electrophysiological data of 1185 patients from January 2014 to December 2019 in the Peking Union Medical College Hospital ALS database were reviewed.The sensitivity of the Gold Coast criteria was compared to that of the possible rEEC and Awaji criteria(defined by the proportion of patients categorized as definite,probable,or possible ALS).Results:A final diagnosis of ALS was recorded in 1162 patients.The sensitivity of the Gold Coast criteria(96.6%,95%confidence interval[CI]=95.3%-97.5%)was greater than that of the rEEC(85.1%,95%CI=82.9%-87.1%)and Awaji(85.3%,95%CI=83.2%-87.3%).In addition,the sensitivity of the novel criteria maintained robust across subgroups,and the advantage was more prominent in limb-onset ALS patients and those who completed electromyographic tests.In those who did not achieve any of the rEEC diagnostic categories,the sensitivity of Gold Coast criteria was 84.4%.Conclusions:The current study demonstrated that the Gold Coast criteria exhibited greater diagnostic sensitivity than the rEEC and Awaji criteria in a Chinese ALS population.The application of the Gold Coast criteria should be considered in clinical practice and future therapeutic trials. 展开更多
关键词 Amyotrophic lateral sclerosis Diagnostic criteria Gold Coast Sensitivity
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Task Coordination Organization Model and the Task Allocation Algorithm for Resource Contention of the Syncretic System
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作者 Danfeng Wu Guangping Zeng +2 位作者 di he Zhaopeng Qian Qingchuan Zhang 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2016年第4期459-470,共12页
At present, robot embedded systems have some common problems such as closure and poor dynamic evolution. Aiming at resolving this situation, our paper focuses on improvements to the robot embedded system and sets up a... At present, robot embedded systems have some common problems such as closure and poor dynamic evolution. Aiming at resolving this situation, our paper focuses on improvements to the robot embedded system and sets up a new robot system architecture, and we propose a syncretic mechanism of a robot and SoftMan (SM). In the syncretic system, the structural organization of the SoftMan group and its modes are particularly important in establishing the task coordination mechanism. This paper, therefore, proposes a coordination organization model based on the SoftMan group, and studies in detail the process of task allocation for resource contention, which facilitates a rational allocation of system resources. During our research, we introduced Resource Requirement Length Algorithm (RRLA) to calculate the resource requirements of the task and a resource conformity degree allocation algorithm of Resource Conformity Degree Algorithm (RCDA) for resource contention. Finally, a comparative evaluation of RCDA with five other frequently used task allocation algorithms shows that RCDA has higher success and accuracy rates with good stability and reliability. 展开更多
关键词 SOFTMAN ROBOT syncretic system organization model task allocation game theory
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Mechanistic insight into the biofilm formation and process performance of a passive aeration ditch(PAD)for decentralized wastewater treatment
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作者 Jibin Li Jinxing Ma +3 位作者 Li Sun Xin Liu Huaiyu Liao di he 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2022年第7期35-46,共12页
Decentralized wastewater containing elevated salinity is an emerging threat to the local environment and sanitation in remote coastal communities.Regarding the cost and treatment efficiencies,we propose a passive aera... Decentralized wastewater containing elevated salinity is an emerging threat to the local environment and sanitation in remote coastal communities.Regarding the cost and treatment efficiencies,we propose a passive aeration ditch(PAD)using non-woven polyester fabric as a feasible bubbleless aerator and biofilm carrier for wastewater treatment.Consideration has been first given to PAD’s efficacy in treating saline decentralized wastewater,and then to the impact of chemical oxygen demand-to-nitrogen(C/N)ratio and salinity on biofilm formation.A multispecies model incorporating the salinity effect has been developed to depict the system performance and predict the microbial community.Results showed that the PAD system had great capacity for pollutants removal.The biofilm thickness increased at a higher C/N ratio because of the boost of aerobic heterotrophs and denitrifying bacteria,which consequently improved the COD and total nitrogen removal.However,this led to the deterioration of ammonia removal.Moreover,while a higher salinity benefited the biofilm growth,the contaminant removal efficiencies decreased because the salinity inhibited the activity of aerobic heterotrophs and reduced the abundance of nitrifying bacteria inside the biofilm.Based on the model simulation,feed water with salinity below 2%and C/N ratio in a range of 1 to 3 forms a biofilm that can reach relatively high organic matter and ammonia removal.These findings not only show the feasibility of PAD in treatment of saline decentralized wastewater,but also offer a systematic strategy to predict and optimize the process performance. 展开更多
关键词 Decentralized wastewater Passive aeration ditch Biofilm formation C/N ratio SALINITY Model simulation
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Channel Modeling for Air-to-Ground Wireless Communication
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作者 Yingcheng Shi di he +1 位作者 Bin Li Jianwu Dou 《ZTE Communications》 2015年第2期41-45,共5页
In this paper, we discuss several large-scale fading models for different enviromnents. The COST231-Hata model is adapted for air-to-ground modeling. We propose two criteria for air-to- ground channel modelling based ... In this paper, we discuss several large-scale fading models for different enviromnents. The COST231-Hata model is adapted for air-to-ground modeling. We propose two criteria for air-to- ground channel modelling based on test data derived from field testing in Beijing. We develop a new propagation model that is more suitable for air-to-ground communication that previous models. We focus on improving this propagation model using the field test data. 展开更多
关键词 air-to-ground communication large-scale fading model
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Variation in Sunshine Duration and Related Aerosol Influences at Shangdianzi GAW Station, China: 1958–2021
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作者 Weijun QUAN Zhiqiang MA +13 位作者 Ziming LI Xiaolan LI Yingruo LI Xiangao XIA Huaigang ZHOU Hujia ZHAO Zhenfa WANG Weiwei PU Fan DONG di he Liyan ZHOU Qingfeng SHI Wenyan WANG Fang JIA 《Journal of Meteorological Research》 SCIE CSCD 2023年第4期551-563,共13页
Sunshine duration(SD) is adopted widely to study global dimming/brightening. However, long-term simultaneous measurements of SD and closely related impact factors require further analysis to elucidate how and why SD h... Sunshine duration(SD) is adopted widely to study global dimming/brightening. However, long-term simultaneous measurements of SD and closely related impact factors require further analysis to elucidate how and why SD has varied during the past decades. In this study, a long-term(1958–2021) SD data series obtained from the Shangdianzi Global Atmosphere Watch(GAW) station in China was analyzed to detect linear trends, climatic jumps, and climatic periods in SD using linear fitting, the Mann–Kendall trend test, and the continuous wavelet transform method. Annual SD exhibited steady dimming(-67.3 h decade-1) before 2010, followed by a period of brightening(189.9 h decade-1)during 2011–2020. An abrupt jump in annual SD occurred in 1995, and the annual SD anomaly exhibited significant oscillation with ~3-yr periodicity during 1960–1978. Partial least squares analysis revealed that annual SD anomaly was associated with variations in relative humidity, gale days, cloud cover, and black carbon(BC). Further analysis of the clear-sky daily sunshine percentage(DSP) and simultaneous measurements of aerosol properties, including aerosol optical depth, aerosol extinction coefficient, single scattering albedo(SSA), BC, and total suspended particulates, suggested that variation in DSP was affected primarily by aerosol scattering and absorption. Furthermore, the hourly clear-sky SD at high aerosol loading was approximately 60% and 56% of that at middle and low aerosol loadings, respectively. The pattern of diurnal variation in clear-sky hourly SD, as well as the actual values, can be affected by the fine particulate concentration, aerosol extinction coefficient, and SSA. 展开更多
关键词 sunshine duration global dimming/brightening multitemporal-scale variation partial least squares Shangdianzi
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载气热提取法测定熔敷金属中扩散氢收集条件的探究
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作者 金浩 邸赫 +2 位作者 马青军 宋南 王博健 《机械制造文摘(焊接分册)》 2019年第2期25-28,共4页
探究了GB/T 3965—2012《熔敷金属中扩散氢测定方法》中载气热提取法收集条件对测定扩散氢含量的影响,并与水银法进行了对比。研究结果表明,样本炉温设定为400℃,A型试块的内部温度大约在51 min时稳定在358℃左右,B型试块内部温度大约在... 探究了GB/T 3965—2012《熔敷金属中扩散氢测定方法》中载气热提取法收集条件对测定扩散氢含量的影响,并与水银法进行了对比。研究结果表明,样本炉温设定为400℃,A型试块的内部温度大约在51 min时稳定在358℃左右,B型试块内部温度大约在27 min时稳定在391℃左右;载气热提取法电信号曲线收集结束点的电信号及斜率均接近0时获得的结果与水银法具有较好的一致性。 展开更多
关键词 扩散氢 载气热提取法 水银法 收集时间 试块内部温度
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Application of permanganate in the oxidation of micropollutants:a mini review 被引量:8
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作者 Xiaohong GUAN di he +1 位作者 Jun MA Guanghao CheN 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2010年第4期405-413,共9页
As a green oxidant,permanganate has received considerable attention for the removal of micropollutants in drinking water treatment.To provide a better understanding of the oxidation of organic micropollutants with per... As a green oxidant,permanganate has received considerable attention for the removal of micropollutants in drinking water treatment.To provide a better understanding of the oxidation of organic micropollutants with permanganate,the oxidation kinetics of 32 micropollutants were compiled.The pollutants include algal toxins,endocrine disrupting chemicals(EDCs),and pharmaceuticals.The oxidation kinetics of micropollutants by permanganate were found to be first order with respect to both contaminant and permanganate concentrations from which second-order rate constants(k″)were obtained.Permanganate oxidized the heterocyclic aromatics with vinyl moiety(i.e.,microcystins,carbamazepine,and dichlorvos)by the addition of double bonds.For the polycyclic aromatic hydrocarbons(PAHs)with alkyl groups,permanganate attacked the benzylic C-H through abstraction of hydrogen.The mechanism for the oxidation of phenolic EDCs by permanganate was a single electron transfer and aromatic ring cleavage.The presence of background matrices could enhance the oxidation of some phenolic EDCs by permanganate,including phenol,chlorinated phenols,bisphenol A,and trichlosan.The toxicity of dichlorvos solution increased after permanganate oxidation,and the estrogenic activity of bisphnol A/estrone increased significantly at the beginning of permanganate oxidation.Therefore,the toxicity of degradation products or intermediates should be determined in the permanganate oxidation processes to better evaluate the applicability of permanganate.The influence of background ions on the permanganate oxidation process is far from clear and should be elucidated in the future studies to better predict the performance of permanganate oxidation of micropollutants.Moreover,methods should be employed to catalyze the permanganate oxidation process to achieve better removal of micropollutants. 展开更多
关键词 pharmaceuticals endocrine disrupting chemicals(EDCs) algal toxins PERMANGANATE OXIDATION
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In vitro Dosimetric Study of Biliary Stent Loaded with Radioactive ^125I Seeds 被引量:3
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作者 Li-Hong Yao Jun-Jie Wang +7 位作者 Charles Shang Ping Jiang Lei Lin Hai-Tao Sun Lu Liu Hao Liu di he Rui-Jie Yang 《Chinese Medical Journal》 SCIE CAS CSCD 2017年第9期1093-1099,共7页
Background: A novel radioactive ^125I seed-loaded biliary stent has been used for patients with malignant biliary obstruction. However, the dosimetric characteristics of the stents remain unclear. Therefore, we aimed... Background: A novel radioactive ^125I seed-loaded biliary stent has been used for patients with malignant biliary obstruction. However, the dosimetric characteristics of the stents remain unclear. Therefore, we aimed to describe the dosimetry of the stents of different lengths -- with different number as well as activities of ^125I seeds. Methods: The radiation dosimetry of three representative radioactive stent models was evaluated using a treatment planning system (TPS), thermoluminescent dosimeter (TLD) measurements, and Monte Carlo (MC) simulations. In the process of TPS calculation and TLD measurement, two different water-equivalent phantoms were designed to obtain cumulative radial dose distribution. Calibration procedures using TLD in the designed phantom were also conducted. MC simulations were performed using the Monte Carlo N-Particle extended version 2.5 general purpose code to calculate the radioactive stent's three-dimensional dose rate distribution in liquid water. Analysis of covariance was used to examine the factors influencing radial dose distribution of the radioactive stent. Results: The maximum reduction in cumulative radial dose was 26% when the seed activity changed from 0.5 mCi to 0,4 mCi for the same length of radioactive stents. The TLD's dose response in the range of 0-10 mGy irradiation by ^137Cs y-ray was linear: y = 182225x - 6651.9 (R2 = 0.99152; y is the irradiation dose in mGy, x is the TLDs' reading in nC). When TLDs were irradiated by different energy radiation sources to a dose of 1 mGy, reading of TLDs was different. Doses at a distance of 0.1 cm from the three stents' surface simulated by MC were 79, 93, and 97 Gy. Conclusions: TPS calculation, TLD measurement, and MC simulation were performed and were found to be in good agreement. Although the whole experiment was conducted in water-equivalent phantom, data in our evaluation may provide a theoretical basis for dosimetry for the clinical application. 展开更多
关键词 BRACHYTHERAPY Computer Simulation PHANTOM RADIOMETRY Thermoluminescent Dosimetry
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Long-term declining in carbon monoxide(CO)at a rural site of Beijing during 2006-2018 implies the improved combustion efficiency and effective emission control 被引量:1
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作者 Yingruo Li Zhiqiang Ma +5 位作者 Tingting Han Weijun Quan Junxia Wang Huaigang Zhou di he Fan Dong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第5期432-442,共11页
Carbon monoxide(CO)is primarily the result of incomplete combustion,which has impor-tant impacts on the atmospheric chemical cycle and climate.Improved quantitative char-acterization of long-term CO trends is importan... Carbon monoxide(CO)is primarily the result of incomplete combustion,which has impor-tant impacts on the atmospheric chemical cycle and climate.Improved quantitative char-acterization of long-term CO trends is important for both atmospheric modeling and the design and implementation of policies to efficiently control multiple pollutants.Due to the limitations of high time-resolution and high-quality long-term observational data,studies on long-term trends in the CO concentration in China are quite limited.In this study,the observational data of the concentration of CO in a rural site of Beijing during 2006-2018 was used to analyze the long-term trend in CO concentration in Beijing.The Theil-Sen method and the generalized additive model(GAM)-based method,were used to conduct the trend estimation analysis.We found that the concentration of CO at the Shangdianzi site showed a significant downward trend during 2006-2018,with a decline rate of 22.8±5.1 ppbV per year.The declining trend in CO also showed phasic characteristics,with a fast decreasing rate during the period of 2006-2008,stable variations during the period of 2009-2013 and a continuous downward trend after 2013.The declining trend in the CO concentration in the south to west(S-W)sectors where the polluted air masses come from is more rapid than that in the sectors where the clean air masses come from.The declining trend in the CO concentration implies the improved combustion efficiency and the successful air pollution control policies in Beijing and the surrounding area. 展开更多
关键词 Carbon monoxide Long-term trend Theil-Sen method Generalized additive model (GAM)-based method Stratified analysis
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Ligand-mediated contaminant degradation by bare and carboxymethyl cellulose-coated bimetallic palladium-zero valent iron nanoparticles in high salinity environments
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作者 Xiaoming Ma di he +2 位作者 Adele M.Jones T.David Waite Taicheng An 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第3期303-311,共9页
The application of nanoscale zero-valent iron(nZVI) for the degradation of contaminants has been extensively investigated, however, few studies have focused on degradation in high salinity environments. In this study,... The application of nanoscale zero-valent iron(nZVI) for the degradation of contaminants has been extensively investigated, however, few studies have focused on degradation in high salinity environments. In this study, the ability of bare and carboxymethyl cellulose(CMC)-coated bimetallic Pd-nZVI particles to degrade 33′44′-tetrachlorobiphenyl in high saline water(SW) is examined with particular attention given to the effects of ethylenediaminetetraacetic acid(EDTA) on the rate of degradation. EDTA enhances the reactivity of Pd-nZVI in SW, with evidence provided to link this to the removal of the passivating layer. Additionally, a conceptual model is proposed which provides a quantitative description of the removal of these iron oxide layers in the presence of EDTA. An optimum EDTA to bare Pd-nZVI molar ratio of 0.1 exists, with insufficient EDTA unable to remove the passivating layer whilst excess EDTA results in Fe loss and enhanced agglomeration due to magnetic attraction of the bare Fe(0) particles. In contrast, CMCcoating of Pd-nZVI assemblages actually impedes degradation, despite the coated particles displaying a smaller average size compared to uncoated particles, with even the presence of EDTA in this case not significantly improving degradation. The reduced reactivity in the presence of CMC is primarily attributed to the effect of CMC on the association of Pd with nZVI particles. In particular, the presence of CMC reduced the total amount of Pd incorporated with the stabilized particles compared to the non-stabilized particles.Additionally, the presence of CMC results in less Pd present in its reactive zero-valent oxidation state. 展开更多
关键词 BIMETALLIC zero valent iron ligand-mediated depassivation POLYCHLORINATED BIPHENYLS high salinity water
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Heterostructure TiO2 polymorphs design and structure adjustment for photocatalysis
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作者 di he heng Su +5 位作者 Xueqiao Li Haijun Yu Muhammad Zubair Lin Wang Shengcheng Mao Jinshu Wang 《Science Bulletin》 SCIE EI CSCD 2018年第5期314-321,共8页
Atomic composite-structure materials play an important role in energy generation and storage application fields for their advanced performance.Constructing heterostructured semiconductors is a promising strategy to de... Atomic composite-structure materials play an important role in energy generation and storage application fields for their advanced performance.Constructing heterostructured semiconductors is a promising strategy to devise photocatalytic systems with high activity.However,most studied hererostructures are those semiconductors with different materials formed by multi-steps,researches on in-situ formed hererostructure originated from the same precursor are few reported,and the effects of different structure ratios on photocatalytic performance are ambiguous.Here,according to in-situ temperature X-ray diffraction and transmission electron microscope techniques,a nano-sized in-situ formed heterostructure of TiO_2semiconductors with anatase and TiO_2-B crystalline structures were designed,their structure ratios were adjusted,the heterostructure interface and photocatalytic reaction mechanism were also detected.Results show that high-quality heterojunction and optimum structure ratios have vital influence on photocatalytic performance,there is an obvious synergetic effect between anatase and TiO_2-B structure,degradation reactions on methyl orange(MO)under ultraviolet light irradiation prove that the highest activity toward MO removal can be obtained for material with 82.5%anatase structure. 展开更多
关键词 PHOTOCATALYSIS ANATASE TiO2-B Structure ratios HETEROJUNCTIONS
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