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Regulating^(*)COOH intermediate via amino alkylation engineering for exceptionally effective photocatalytic CO_(2) reduction
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作者 Chengcheng Chen Qiaoyu Zhang +3 位作者 Fangting liu Zhengguo Zhang qiong liu Xiaoming Fang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期282-291,共10页
Photocatalytic reduction of CO_(2) into fuel represents a promising approach for achieving carbon neutrality,while realizing high selectivity in this process is challenging due to uncontrollable reaction intermediate ... Photocatalytic reduction of CO_(2) into fuel represents a promising approach for achieving carbon neutrality,while realizing high selectivity in this process is challenging due to uncontrollable reaction intermediate and retarded desorption of target products.Engineering the interface microenvironment of catalysts has been proposed as a strategy to exert a significant influence on reaction outcomes,yet it remains a significant challenge.In this study,amino alkylation was successfully integrated into the melem unit of polymeric carbon nitrides(PCN),which could efficiently drive the photocatalytic CO_(2) reduction.Experimental characterization and theoretical calculations revealed that the introduction of amino alkylation lowers the energy barrier for CO_(2) reduction into^(*)COOH intermediate,transforming the adsorption of^(*)COOH intermediate from the endothermic to an exothermic process.Notably,the as-prepared materials demonstrated outstanding performance in photocatalytic CO_(2) reduction,yielding CO_(2)at a rate of 152.8μmol h^(-1) with a high selectivity of 95.4%and a quantum efficiency of 6.6%. 展开更多
关键词 Polymeric carbonnitride Regulate intermediate Photocatalytic CO_(2)reduction Amino alkylation ^(*)COOH adsorption
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Current optimization-based control of dual three-phase PMSM for low-frequency temperature swing reduction
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作者 Linlin Lu Xueqing Wang +3 位作者 Luhan Jin qiong liu Yun Zhang Yao Mao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期238-246,共9页
In this paper,a control scheme based on current optimization is proposed for dual three-phase permanent-magnet synchronous motor(DTP-PMSM)drive to reduce the low-frequency temperature swing.The reduction of temperatur... In this paper,a control scheme based on current optimization is proposed for dual three-phase permanent-magnet synchronous motor(DTP-PMSM)drive to reduce the low-frequency temperature swing.The reduction of temperature swing can be equivalent to reducing maximum instantaneous phase copper loss in this paper.First,a two-level optimization aiming at minimizing maximum instantaneous phase copper loss at each electrical angle is proposed.Then,the optimization is transformed to a singlelevel optimization by introducing the auxiliary variable for easy solving.Considering that singleobjective optimization trades a great total copper loss for a small reduction of maximum phase copper loss,the optimization considering both instantaneous total copper loss and maximum phase copper loss is proposed,which has the same performance of temperature swing reduction but with lower total loss.In this way,the proposed control scheme can reduce maximum junction temperature by 11%.Both simulation and experimental results are presented to prove the effectiveness and superiority of the proposed control scheme for low-frequency temperature swing reduction. 展开更多
关键词 Dual three-phase PMSM Low-frequency temperature swing Copper loss Current optimization Connected neutral points
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A Systematic Review of Contrast-Induced Acute Kidney Injury
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作者 Xing Li qiong liu 《Open Journal of Nephrology》 2024年第2期185-195,共11页
Background: Contrast-induced acute kidney injury (CI-AKI) is the third most common cause of AKI in hospitalized patients. Contrast agents mainly cause acute kidney injury through hypoxic damage to renal parenchyma and... Background: Contrast-induced acute kidney injury (CI-AKI) is the third most common cause of AKI in hospitalized patients. Contrast agents mainly cause acute kidney injury through hypoxic damage to renal parenchyma and toxic effects on renal capillaries and tubules. Patients with CI-AKI are more likely to experience adverse events, including longer hospital stay and costs, longer ICU stay, and higher mortality rates. This article elaborates on the definition, epidemiology, risk factors, pathogenesis, and prevention strategies of CI-AKI. Methods: We conducted an extensive literature search using contrast agents and AKI as keywords to identify relevant studies on CI-AKI. Conclusion: CI-AKI is a significant clinical challenge that requires a multifaceted approach to prevention and management. Understanding the risk factors, pathophysiology, and current best practices is essential for healthcare providers to optimize patient care and improve outcomes in those undergoing contrast-enhanced imaging procedures. Hydration therapy is currently the main prevention method, but antioxidants may also become a new strategy. 展开更多
关键词 CI-AKI ROS Preventive Strategies ANTIOXIDANTS
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成纤维细胞生长因子-23与慢性肾脏病患者矿物质代谢紊乱的相关性研究 被引量:5
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作者 胡志娟 史亚男 +3 位作者 刘琼 董春霞 牛凯 刘冰 《中国现代医学杂志》 CAS 2019年第21期95-99,共5页
目的观察慢性肾脏病(CKD)非透析患者的血清钙、磷、全段甲状旁腺激素(iPTH)、25-羟维生素D、成纤维细胞生长因子-23(FGF-23)水平,以及肱踝脉搏波传导速度(baPWV),并探讨FGF-23与上述指标的相关性。方法选取河北省人民医院35例健康者(对... 目的观察慢性肾脏病(CKD)非透析患者的血清钙、磷、全段甲状旁腺激素(iPTH)、25-羟维生素D、成纤维细胞生长因子-23(FGF-23)水平,以及肱踝脉搏波传导速度(baPWV),并探讨FGF-23与上述指标的相关性。方法选取河北省人民医院35例健康者(对照组)、34例CKD 1期、35例CKD 2期、34例CKD 3a期、33例CKD 3b期、38例CKD 4期和32例CKD 5期患者。检测各组患者的血压、体重指数(BMI)、血清白蛋白、肌酐、钙、磷、25-羟维生素D、iPTH、FGF23水平及baPWV。结果对照组及CKD各期患者的年龄、性别构成及BMI无差异(P>0.05)。与对照组比较,CKD 3a^5期组和CKD 2~5期组患者的收缩压和舒张压升高(P<0.05);CKD各期患者的24 h尿白蛋白定量升高(P<0.05),CKD 3a^5期组患者的血肌酐、血磷、iPTH水平升高,血清白蛋白、血钙水平下降(P<0.05);CKD 2~5期组患者的25-羟维生素D水平下降,CKD 3a^5期组患者的FGF-23水平升高(P<0.05);7组不同水平25-羟维生素D例数所占比例比较有差异(P<0.05);与对照组及CKD 1期组分别比较,CKD 3a^5期组患者的baPWV加快(P<0.05);所有CKD患者中血清FGF-23与血钙(r=-0.175,P=0.000)、25-羟维生素D(r=-0.130,P=0.000)呈负相关,与血磷(r=0.236,P=0.000)、iPTH(r=0.249,P=0.000)呈正相关。结论CKD患者血清iPTH、FGF-23水平的变化先于血钙、磷的变化。随着eGFR的降低,25-羟维生素D的下降时间早于iPTH和FGF-23水平的升高。在CKD的早期即出现血管僵硬度增加。 展开更多
关键词 慢性肾脏病-矿物质和骨代谢紊乱/肾疾病 25-羟维生素D 甲状旁腺素 成纤维细胞生长因子-23
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多层楼房式猪舍自动化通风与臭气净化系统的设计与应用 被引量:5
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作者 佘德勇 汪雅 +4 位作者 余道伦 刘瑶 刘琼 左瑞华 吴中红 《猪业科学》 2021年第6期56-59,共4页
楼房式猪舍因其节约土地、方便管理等突出优点,在越来越多的地方被采用。由于楼房式养殖的饲养密度更大,所以其通风设计与舍外场区环境控制显得尤为重要。文章针对大跨度小单元楼房式猪舍,设计了一种通风与臭气净化相结合的新型通风工... 楼房式猪舍因其节约土地、方便管理等突出优点,在越来越多的地方被采用。由于楼房式养殖的饲养密度更大,所以其通风设计与舍外场区环境控制显得尤为重要。文章针对大跨度小单元楼房式猪舍,设计了一种通风与臭气净化相结合的新型通风工艺。夏季采用湿帘-定速风机模式通风降温,保证高效率通风降温;冬季采用檐下通风小窗-吊顶通风窗-变频风机模式,变频风机转速随着氨气浓度上升而相应加大,这种方式可以保证通风效果的同时确保最大程度减少舍内热量损失。在出风端,增加臭气净化处理工艺,利用添加生物菌剂的水循环过滤墙将猪舍排出的臭气通过水洗过滤,降低排出气体中的臭味物质浓度,改善养殖场区空气环境。整套工艺采用智能化控制,实现对系统的精准控制,同时节能降耗,提高养殖场的总体效益。 展开更多
关键词 楼房式猪舍 纵向通风 智能控制 通风工艺 臭气净化
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死亡危重型手足口病临床特点分析
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作者 陈韬 王美芬 +4 位作者 杜曾庆 罗云娇 王明英 柳琼 邓成俊 《亚洲儿科病例研究》 2018年第1期6-12,共7页
目的:探讨进入IV期危重型手足口病(Hand-mouth and foot disease, HFMD)死亡的临床特点、诊治经过及死亡分析,总结经验及教训。方法:采用回顾性分析方法对2009年1月至2014年12月昆明周边及地州转入我院救治19例危重型HFMD患儿的临床资... 目的:探讨进入IV期危重型手足口病(Hand-mouth and foot disease, HFMD)死亡的临床特点、诊治经过及死亡分析,总结经验及教训。方法:采用回顾性分析方法对2009年1月至2014年12月昆明周边及地州转入我院救治19例危重型HFMD患儿的临床资料进行分析。结果:19例患儿来自农村,其中男性13例(68.42%),女性6例(31.58%),3岁以下16例,占84.21%,3岁以上3例,占15.79%。所有病例均有发热、惊跳、肢体抖动的表现。16例患儿入院时出现肺出血、呼吸循环衰竭的表现。17例患儿均出现白细胞总数及中性粒细胞、超敏C-反应蛋白升高,12例血糖升高。4例合并消化道出血,1例同时合并肾功能衰竭。病原学:18例EV71阳性,1例为其它未定型肠道病毒感染。结论:早期识别并及时治疗第2期HFMD病例,及时进行干预,避免进展为危重型HFMD,危重型HFMD主要由EV71病毒感染引起,致死率高,进入IV期危重型HFMD出现神经源性肺水肿、肺出血、呼吸循环衰竭、严重脑功能障碍等严重并发症,死亡率高。 展开更多
关键词 HFMD 危重型 循环功能障碍 神经源性肺水肿 肺出血 EV71
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Chaihu-Shugan-San exerts an antidepressive effect by downregulating miR-124 and releasing inhibition of the MAPK14 and Gria3 signaling pathways 被引量:29
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作者 qiong liu Ning-Ning Sun +2 位作者 Zheng-Zhi Wu Da-Hua Fan Mei-Qun Cao 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第5期837-845,共9页
Dysregulation of mi R-124 has been reported to be involved in the pathophysiology of depression. Chaihu-Shugan-San, a traditional Chinese medicine, has antidepressive activity; however, the underlying mechanisms remai... Dysregulation of mi R-124 has been reported to be involved in the pathophysiology of depression. Chaihu-Shugan-San, a traditional Chinese medicine, has antidepressive activity; however, the underlying mechanisms remain unclear. In this study, to generate a rodent model of depression, rats were subjected to a combination of solitary confinement and chronic unpredictable mild stress for 28 days. Rats were intragastrically administered Chaihu-Shugan-San(2.835 m L/kg/d) for 4 weeks, once a day. Real-time reverse-transcription quantitative polymerase chain reaction, mi RNA microarray, western blot assay and transmission electron microscopy demonstrated that ChaihuShugan-San downregulated mi R-124 expression and upregulated the m RNA and protein levels of mitogen-activated protein kinase 14(MAPK14) and glutamate receptor subunit 3(Gria3). Chaihu-Shugan-San also promoted synapse formation in the hippocampus. The open field test, sucrose consumption test and forced swimming test were used to assess depression-like behavior. After intragastric administration of Chaihu-Shugan-San, sucrose consumption increased, while the depressive behaviors were substantially reduced. Together, these findings suggest that Chaihu-Shugan-San exerts an antidepressant-like effect by downregulating mi R-124 expression and by releasing the inhibition of the MAPK14 and Gria3 signaling pathways. 展开更多
关键词 nerve regeneration traditional Chinese medicine Chaihu-Shugan-San DEPRESSION open-field test sucrose consumption test forced swimming test miR-124 neural plasticity MAPK14 Gria3 neural regeneration
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Beneficial effects of moderate to vigorous physical activity on cardiovascular disease among Chinese adults 被引量:21
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作者 qiong liu Fang-Chao liu +16 位作者 Ke-Yong HUANG Jian-Xin LI Xue-Li YANG Xin-Yan WANG Ji-Chun CHEN Xiao-Qing liu Jie CAO Chong SHEN Ling YU Fang-Hong LU Xian-Ping WU Lian-Cheng ZHAO Ying LI Dong-Sheng HU Xiang-Feng LU Jian-Feng HUANG Dong-Feng GU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2020年第2期85-95,共11页
Background In China,lack of evidence remains a significant challenge for the national initiative to promote physical activity(PA).We aimed to quantify the beneficial effects of meeting or maintaining the recommended P... Background In China,lack of evidence remains a significant challenge for the national initiative to promote physical activity(PA).We aimed to quantify the beneficial effects of meeting or maintaining the recommended PA level[150 minutes per week(min/wk)of moderate PA or 75 min/wk of vigorous PA or an equivalent combination]on incident cardiovascular disease(CVD)among Chinese population.Methods We included 100,560 participants without history of CVD from three cohorts in the Prediction for Atherosclerotic Cardiovascular Disease Risk in China(China-PAR)project.Cox proportional hazards models were used to estimate hazard ratios(HRs)and 95%confidence intervals(CIs)for CVD events and its subtypes,including stroke,coronary heart disease,heart failure,and CVD death.Results During a median follow-up of 7.3 years(range:6–15 years),777,163 person-years and 4693 incident CVD events were observed.Compared with participants who were inactive at baseline,the multivariable adjusted HR(95%CI)of developing CVD was 0.74(0.69–0.79)for those who met recommended moderate to vigorous physical activity(MVPA)level at baseline.Furthermore,the risk of CVD incidence was reduced with increment of MVPA(Ptrend<0.001),and the HR(95%CI)of highly-active versus inactive category was 0.62(0.56–0.68).Compared with individuals who were inactive both at the baseline and follow-up,those keeping active over the period of follow-up had a substantial lower risk of incident CVD with the HR(95%CI)of 0.57(0.43–0.77).Conclusions The findings demonstrated that meeting and maintaining the recommended MVPA level could reduce the cardiovascular risk.Wider adoption of the PA recommendations would have considerable health impacts to the Chinese population. 展开更多
关键词 Cardiovascular disease China Cohort study Physical activity
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Hydrogen-rich water ameliorates neuropathological impairments in a mouse model of Alzheimer's disease through reducing neuroinflammation and modulating intestinal microbiota 被引量:8
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作者 Yi-Tong Lin Qing-Qing Shi +6 位作者 Lei Zhang Cai-Ping Yue Zhi-Jun He Xue-Xia Li Qian-Jun He qiong liu Xiu-Bo Du 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第2期409-417,共9页
Hydrogen exhibits the potential to treat Alzheimer's disease. Stereotactic injection has been previously used as an invasive method of administering active hydrogen, but this method has limitations in clinical pra... Hydrogen exhibits the potential to treat Alzheimer's disease. Stereotactic injection has been previously used as an invasive method of administering active hydrogen, but this method has limitations in clinical practice. In this study, triple transgenic(3×Tg) Alzheimer's disease mice were treated with hydrogen-rich water for 7 months. The results showed that hydrogen-rich water prevented synaptic loss and neuronal death, inhibited senile plaques, and reduced hyperphosphorylated tau and neurofibrillary tangles in 3×Tg Alzheimer's disease mice. In addition, hydrogen-rich water improved brain energy metabolism disorders and intestinal flora imbalances and reduced inflammatory reactions. These findings suggest that hydrogen-rich water is an effective hydrogen donor that can treat Alzheimer's disease. This study was approved by the Animal Ethics and Welfare Committee of Shenzhen University, China(approval No. AEWC-20140615-002) on June 15, 2014. 展开更多
关键词 Alzheimer's disease amyloid-β ANTI-INFLAMMATION BIOENERGETICS gut microbiota hydrogen therapy neurodegenerative disease neurofibrillary tangles
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Geological resources and environmental carrying capacity evaluation review,theory, and practice in China 被引量:19
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作者 Rui-min Li Zhi-qiang Yin +3 位作者 Yi Wang Xiao-lei Li qiong liu Meng-meng Gao 《China Geology》 2018年第4期556-565,共10页
Evaluations of resources and environmental carrying capacities (GRECC)are the premise of land space planning and use control.Resource allocations and environmental capacity are the basic conditions that restrict devel... Evaluations of resources and environmental carrying capacities (GRECC)are the premise of land space planning and use control.Resource allocations and environmental capacity are the basic conditions that restrict development in a region.In this paper,based on a systematic review of China's geological environment,groundwater resources,mineral resources,other geological resources and the environmental carrying capacity research status,the relationship between the natural resource environmental system and the socio-economic system is studied.Then a "coordination theory of resources and environmental carrying"is proposed.Next,on the basis of an evaluation experiment performed at different scales and for different types of regions,the technical methods for an evaluation of the geological resources and environmental carrying capacity at the regional (inter-provincial)and provincial scales in China are established for the first time.This paper presents a standardized method based on technical ideas, evaluation methods,and index systems for geological resource and environmental carrying capacity evaluation.Finally,an evaluation of the groundwater resource carrying capacity in China is used as an example for the demonstration of the groundwater resource background and use of state evaluation methods. 展开更多
关键词 GEOLOGICAL ENVIRONMENT GROUNDWATER RESOURCES RESOURCE and ENVIRONMENT Carrying capacity Evaluation
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Radioprotective effects of cimetidine on rats irradiated by long-term, low-dose-rate neutrons and ^(60)Coγ-rays 被引量:6
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作者 Ding-Wen Jiang Qing-Rong Wang +8 位作者 Xian-Rong Shen Ying He Tian-Tian Qian qiong liu Deng-Yong Hou Yu-Ming liu Wei Chen Xin Ren Ke-Xian Li 《Military Medical Research》 SCIE CAS 2017年第3期141-148,共8页
Background: Cimetidine, an antagonist of histamine type II receptors, has shown protective effects against γ-rays or neutrons. However, there have been no reports on the effects of cimetidine against neutrons combine... Background: Cimetidine, an antagonist of histamine type II receptors, has shown protective effects against γ-rays or neutrons. However, there have been no reports on the effects of cimetidine against neutrons combined with γ-rays. This study was carried out to evaluate the protective effects of cimetidine on rats exposed to long-term, low-dose-rate neutron and γ-ray combined irradiation(n-γ LDR).Methods: Fifty male Sprague-Dawley(SD) rats were randomly divided into 5 groups: the normal control group, radiation model group, 20mg/(kg·d) cimetidine group, 80mg/(kg·d) cimetidine group and 160mg/(kg·d) cimetidine group(10 rats per group). Except for the normal control group, 40 rats were simultaneously exposed to fission neutrons(^(252)Cf, 0.085 m Gy/h) for 22 h every day and γ-rays(^(60)Co, 0.097Gy/h) for 1.03 h once every three days, and the cimetidine groups were administered intragastrically with cimetidine at doses of 20, 80 and 160mg/kg each day. Peripheral blood WBC of the rats was counted the day following exposure to γ-rays. The rats were anesthetized and sacrificed on the day following exposure to ^(252)Cf for 28 days. The spleen, thymus, testicle, liver and intestinal tract indexes were evaluated. The DNA content of bone marrow cells and concanavalin A(Con A)-induced lymphocyte proliferation were measured. The frequency of micronuclei in polychromatic erythrocytes(f MNPCEs), superoxide dismutase(SOD), malondialdehyde(MDA), and glutathione peroxidase(GSH-Px) in the serum and liver tissues were detected.Results: The peripheral blood WBC in the cimetidine groups was increased significantly on the 8th day and the 26 th day compared with those in the radiation model group. The spleen, thymus and testicle indexes of the cimetidine groups were higher than those of the radiation model group. The DNA content of bone marrow cells and lymphocyte proliferation in the cimetidine groups were increased significantly, and fMNPCE was reduced 1.41-1.77 fold in cimetidine treated groups. The activities of SOD and GSH-Px in the cimetidine groups were increased significantly, and the content of MDA in the cimetidine groups was decreased significantly.Conclusions: The results suggested that cimetidine alleviated damage induced by long-term, low-dose-rate neutron and γ combined irradiation via antioxidation and immunomodulation. Cimetidine might be useful as a potent radioprotector for radiotherapy patients as well as for occupational exposure workers. 展开更多
关键词 CIMETIDINE RADIOPROTECTION ANTIOXIDATION IMMUNOMODULATION Micronuclei
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Long-term exposure to fine particulate matter modifies the association between physical activity and hypertension incidence 被引量:5
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作者 qiong liu Keyong Huang +16 位作者 Fengchao Liang Xueli Yang Jianxin Li Jichun Chen Xiaoqing liu Jie Cao Chong Shen Ling Yu Yingxin Zhao Ying Deng Ying Li Dongsheng Hu Xiangfeng Lu Yang liu Dongfeng Gu Fangchao liu Jianfeng Huang 《Journal of Sport and Health Science》 SCIE 2022年第6期708-715,F0003,共9页
Background:The trade-off between the benefits of regular physical activity(PA)and the potentially detrimental effects of augmented exposure to air pollution in highly polluted regions remains unclear.This study aimed ... Background:The trade-off between the benefits of regular physical activity(PA)and the potentially detrimental effects of augmented exposure to air pollution in highly polluted regions remains unclear.This study aimed to examine whether ambient fine particulate matter(PM_(2.5))exposure modified the impacts of PA volume and intensity on hypertension risk.Methods:We included 54,797 participants without hypertension at baseline in a nationwide cohort of the Prediction for Atherosclerotic Cardiovascular Disease Risk in China(China-PAR)project.PA volume and intensitywere assessed by questionnaire,and high-resolution(1 km×1 km)PM_(2.5)estimates were generated using a satellite-based model.Results:During 413,516 person-years of follow-up,12,100 incident hypertension cases were identified.PM_(2.5)significantly modified the relationship between PA and hypertension incidence(p_(interaction)<0.001).Increased PA volume was negatively associated with incident hypertension in the low PM_(2.5)stratum(<59.8μg/m^(3),ptrend<0.001),with a hazard ratio of 0.81(95%confidence interval(95%CI):0.74-0.88)when comparing the fourth with the first quartile of PA volume.However,the health benefits were not observed in the high PM_(2.5)stratum(≥59.8μg/m^(3),p_(trend)=0.370).Moreover,compared with light PA intensity,vigorous intensity was related to a 20%(95%CI:9%-29%)decreased risk of hypertension for participants exposed to low PM_(2.5),but a 17%(95%CI:4%-33%)increased risk for those with high PM_(2.5)levels.Conclusion:PA was associated with a reduced risk of hypertension only among participants with low PM_(2.5)exposure.Our findings recommended regular PA to prevent hypertension in less polluted regions and reinforced the importance of air quality improvement. 展开更多
关键词 Air pollution Cohort study HYPERTENSION Particulate matter Physical activity
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Study on the effect of RDX content on the properties of nitramine propellant 被引量:4
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作者 Fen ZHANG Deng-pan ZHU +2 位作者 qiong liu Zhi-tao liu Ping DU 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2017年第4期246-248,共3页
Four kinds of nitroamine propellants with different RDX contents(10%,20%,30%and 40%)were prepared to study the effect of RDX content on the mechanical properties and combustion properties of nitroamine propellant.The ... Four kinds of nitroamine propellants with different RDX contents(10%,20%,30%and 40%)were prepared to study the effect of RDX content on the mechanical properties and combustion properties of nitroamine propellant.The mechanical properties and combustion properties of nitroamine propellant at the normal temperature(20C)and low temperature(à40C)were test by using impact testing machine,drop hammer impact test machine and closed bomb vessel.The test results show that the impact strength of30%RDX-contained nitramine propellant is maximum,but 40%RDX-contained nitramine propellant has the minimum impact strength.And the crushing height of propellant with 20%RDX-contained was the highest,but the crushing height of propellant with 40%RDX-contained the lowest.With the increase in RDX content in nitramine propellant,the energy of nitramine propellant increases and its burning rate reduces,but 40%RDX-contained nitramine propellant did not meet this trend at the low temperature because of its poor mechanical properties. 展开更多
关键词 NITRAMINE PROPELLANT RDX Mechanical PROPERTY COMBUSTION PROPERTY
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理论设计和实验研究吡啶掺杂聚合氮化碳提升光催化CO_(2)还原性能
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作者 陈成成 刘芳庭 +3 位作者 张巧钰 张正国 刘琼 方晓明 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第3期91-102,共12页
光催化CO_(2)还原是利用太阳光和水将CO_(2)转化为高价值化学品或燃料(如CO、甲醇、甲烷等),被认为是解决CO_(2)问题的理想途径之一.CO_(2)分子中C=O离解能高而活化困难,且光催化CO_(2)还原涉及多质子耦合多电子转移过程且产物多样,因... 光催化CO_(2)还原是利用太阳光和水将CO_(2)转化为高价值化学品或燃料(如CO、甲醇、甲烷等),被认为是解决CO_(2)问题的理想途径之一.CO_(2)分子中C=O离解能高而活化困难,且光催化CO_(2)还原涉及多质子耦合多电子转移过程且产物多样,因而研制效率高且选择性好的光催化剂是该技术的关键.聚合物氮化碳(PCN)作为一种结构可调的有机光催化剂,具有化学稳定性好且能带位置适宜于还原CO_(2)的优势,是一种具有发展潜力的CO_(2)还原光催化剂;但是PCN也存在因其禁带宽度较大而对可见光响应范围有限以及因其结构由三均三嗪单元构成而缺乏足够活性位点来吸附和活化CO_(2)等不足.目前在提升PCN的光催化CO_(2)还原性能方面已有不少研究,但所得的PCN基光催化剂在效率和选择性上仍处于较低水平.考虑到光催化CO_(2)还原涉及复杂的热力学和动力学要求,对基于PCN的光催化剂进行精准设计和研究是非常必要的,这有望获得同时具有可见光吸收增强、光生载流子复合减少、吸附和活化CO_(2)的位点增加以及能带位置适宜等特性的高性能光催化剂.为此,本论文采用理论设计与实验研究相结合的方法,以吡啶掺杂PCN为模型,研制了一种用于CO_(2)还原的高性能PCN基光催化剂.本文设计了将吡啶掺杂到PCN结构单元中不同位置的两种结构,并运用理论计算确定其中禁带宽度较窄、更利于光生载流子分离、更有助于CO_(2)吸附和活化以及总能量较低的结构作为最优结构.然后,采用尿素与适量的2-氨基吡啶共聚的方法,制备了吡啶掺杂的PCN样品,并通过一系列表征确定结构设计成功.还测定了所得吡啶掺杂PCN样品的光学和光电化学特性,评价了它们光催化CO_(2)还原的活性和选择性.最后,通过理论计算和实验研究,阐明了该吡啶掺杂PCN光催化剂的性能增强机制及其光催化还原CO_(2)的反应路径.结果表明,以CO(bpy)_(2)为助催化剂,本文制备的吡啶掺杂PCN(CN-5%AP)光催化剂不仅取得了较高的CO产量,而且还获得99.6%的CO选择性,在λ=420 nm处的表观量子效率可达2.86%.研究表明,该吡啶掺杂的PCN光催化性能增强主要源于其提升的CO_(2)吸附容量以及对CO_(2)还原为CO反应的促进.综上,本工作为设计和制备实现高效CO_(2)还原的光催化剂提供了参考. 展开更多
关键词 光催化CO_(2)还原 先理论后实验 聚合氮化碳 密度泛函理论 吡啶
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Straw mulch-based no-tillage improves tillering capability of dryland wheat by reducing asymmetric competition between main stem and tillers 被引量:4
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作者 Hongkun Yang Yun Xiao +7 位作者 Peng He Dailong Ai Qiaosheng Zou Jian Hu qiong liu Xiulan Huang Ting Zheng Gaoqiong Fan 《The Crop Journal》 SCIE CSCD 2022年第3期864-878,共15页
The moisture-conserving effect of straw mulch-based no-tillage(SMNT)is expected to increase fertile spikes and grain yield in environments with rainfall less than 200 mm.However,the mechanisms under-lying the positive... The moisture-conserving effect of straw mulch-based no-tillage(SMNT)is expected to increase fertile spikes and grain yield in environments with rainfall less than 200 mm.However,the mechanisms under-lying the positive effect of SMNT on wheat tillering are not fully elucidated.A split-plot experiment was designed to investigate the combined effects of SMNT and cultivars on tillering of dryland wheat grown under both dry and favorable climates.Application of SMNT to a cultivar with 1-2 tillers exploited both tillering and kernel-number plasticity,increasing the mean grain yield by 20.5%.This increase was attrib-uted primarily to an increased first-tiller emergence rate resulting from increased N uptake,leaf N con-tent,and N remobilization from tillers to their grain.The second and third tillers,as transient sinks,contributed to the tiller survival rate,which depends on tiller leaf number.The increased total N uptake by SMNT also increased the dry mass yield of tillers and the C:N ratio,reducing the asymmetric compe-tition between main stem and tillers.Owing to these beneficial effects,reduced mitogen-activated pro-tein kinase(MAPK)and abscisic acid signals were observed under SMNT,whereas indole-3-acetic acid(IAA)signals and genes involved in DNA replication and mismatch repair were increased.These signals activated three critical transcription factors(the calmodulin-binding transcription activator,GRAS domain,and cysteine-2/histidine-2 family)and further increased rapid drought response and tiller main-tenance after stem extension.Phenylpropanoid biosynthesis,sphingolipid biosynthesis,and galactose metabolism were most relevant to increased tillering under SMNT because of their critical role in drought response and lignin biosynthesis.Our results suggest that straw mulch-based no-tillage activates rapid drought response and improved wheat tillering by coordinating root N uptake,N remobilization,and asymmetric competition between main stem and tillers. 展开更多
关键词 Straw mulch-basedno-tillage Wheat tillering Stable isotopetracing TRANSCRIPTOME Metabolomics
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Adverse associations of sedentary behavior with cancer incidence and all-cause mortality:A prospective cohort study 被引量:4
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作者 Yuan Lin qiong liu +17 位作者 Fangchao liu Keyong Huang Jianxin Li Xueli Yang Xinyan Wang Jichun Chen Xiaoqing liu Jie Cao Chong Shen Ling Yu Fanghong Lu Xianping Wu Liancheng Zhao Ying Li Dongsheng Hu Xiangfeng Lu Jianfeng Huang Dongfeng Gu 《Journal of Sport and Health Science》 SCIE 2021年第5期560-569,共10页
Background:Inconsistent results have been reported in developed countries for relationships between sedentary behavior and cancer incidence and mortality,and evidence from the Chinese population is scarce.This study a... Background:Inconsistent results have been reported in developed countries for relationships between sedentary behavior and cancer incidence and mortality,and evidence from the Chinese population is scarce.This study aimed to investigate such relationships in large Chinese population-based prospective cohorts and to explore the joint effect and interaction of sedentary behavior and moderate-to-vigorous physical activity(MVPA)on these relationships.Methods:We included 95,319 Chinese adults without cancer from 3 large cohorts and assessed their sedentary behavior and physical activity with a unified questionnaire.Cancer incidence and mortality were confirmed by interviewing participants or their proxies and checking hospital records and death certificates.Hazard ratios(HRs)and 95%confidence intervals(95%CIs)for cancer and mortality were estimated using Cox proportional hazards regression models.Results:During 559,002 person-years of follow-up,2388 cancer events,1571 cancer deaths,and 4562 all-cause deaths were recorded.Sedentary behavior was associated with increased risk of developing cancer and deaths in a doseresponse manner.The multivariable-adjusted HRs(95%CIs)were the following:HR=1.16,95%CI:1.01-1.33;HR=1.24,95%CI:1.04-1.48;and HR=1.15,95%CI:1.04-1.28 for cancer incidence,cancer mortality,and all-cause mortality,respectively,for those having≥10 h/day of sedentary time compared with those having<6 h/day of sedentary time.Sedentary populations(≥10 h/day)developed cancer or died 4.09 years and 2.79 years earlier,respectively,at the index age of 50 years.Failure to achieve the recommended level of MVPA may further aggravate the adverse associations,with the highest cancer and mortality risks being observed among participants with both≥10 h/day of sedentary time and<150 min/week of MVPA.Limitations of this study include the fact that physical activity information was obtained via questionnaire instead of objective measurement and that there were insufficient incident cases for the analysis of associations between sedentary behavior and site-specific cancers.Conclusion:Sedentary behavior was associated with an increased risk of cancer and all-cause mortality among Chinese adults,especially for those with≥10 h/day of sedentary time.It is necessary to reduce sedentary time,in addition to increasing MVPA levels,for the prevention of cancer and premature death. 展开更多
关键词 All-cause mortality CANCER Chinese population Cohort study Sedentary behavior
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体外培养乳牙牙髓干细胞向血管内皮细胞定向分化的实验研究 被引量:6
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作者 刘琼 文军 +1 位作者 吴小明 钱虹 《中国现代医学杂志》 CAS 2019年第1期29-34,共6页
目的研究体外培养乳牙牙髓干细胞向血管内皮细胞的定向分化。方法选取南方医科大学口腔医院29例健康儿童的滞留乳牙,在4 h内进行乳牙牙髓干细胞的原代提取。采用免疫磁珠分选法进行细胞分选,并对分选出的细胞进行特定的血管内皮细胞定... 目的研究体外培养乳牙牙髓干细胞向血管内皮细胞的定向分化。方法选取南方医科大学口腔医院29例健康儿童的滞留乳牙,在4 h内进行乳牙牙髓干细胞的原代提取。采用免疫磁珠分选法进行细胞分选,并对分选出的细胞进行特定的血管内皮细胞定向诱导。对乳牙牙髓干细胞及血管内皮细胞定向诱导后的细胞进行镜下形态观察、血管生成实验,以及免疫表型鉴定。结果镜下形态观察显示,经过血管内皮定向诱导的乳牙牙髓干细胞呈典型血管内皮细胞的形态特征;血管生成实验表明,经过血管内皮定向诱导的乳牙牙髓干细胞可呈现明显的血管样结构;免疫表型鉴定显示经过血管内皮定向诱导的乳牙牙髓干细胞血管内皮细胞表面抗原呈阳性。结论乳牙牙髓干细胞可定向分化为血管内皮细胞。 展开更多
关键词 干细胞 内皮细胞 细胞分化 血管生成实验 免疫表型
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Involvement of moesin phosphorylation in ischemia/reperfusion induced inner blood-retinal barrier dysfunction 被引量:3
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作者 Jing Xu qiong liu +4 位作者 Ming Ma Lin-Jiang Chen Jian Yu Ke Xiong Jing Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第4期545-551,共7页
AIM: To investigate the role of moesin and its underlying signal transduction in retinal vascular damage induced by retinal ischemia-reperfusion(RIR) insult.METHODS: C57 BL/6 mice were subjected to continued ischemia ... AIM: To investigate the role of moesin and its underlying signal transduction in retinal vascular damage induced by retinal ischemia-reperfusion(RIR) insult.METHODS: C57 BL/6 mice were subjected to continued ischemia for 45 min, followed by blood reperfusion. The expression and phosphorylation of moesin in retinal vessels were detected by immunohistochemistry and Western blotting. The inner blood-retinal barrier was evaluated using FITCdextran leakage assay on whole-mount retina. Further studies were conducted to explore the effects of p38 mitogen-activated protein kinase(MAPK) pathway on the involvement of moesin in RIR-evoked retinal vascular hyperpermeability response. RESULTS: It revealed that RIR induced moesin phosphorylation in a time-dependent manner after reperfusion. The phosphorylation of moesin was alleviated by inhibitions of p38 MAPK, while this treatment also ameliorated the dysfunction of inner blood-retinal barrier. CONCLUSION: The results suggest that moesin is involved in RIR-evoked retinal vascular endothelial dysfunction and the phosphorylation of moesin is triggered via p38 MAPK activation. 展开更多
关键词 RETINAL ISCHEMIA-REPERFUSION MOESIN p38 MITOGEN-ACTIVATED protein kinase INNER blood-retinal barrier mice
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Epidemiological and clinical characteristics of COVID-19 patients in Hengyang,Hunan Province,China 被引量:3
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作者 Zhe-Feng Zhong Jia Huang +19 位作者 Xia Yang Jin-Ling Peng Xiao-Yan Zhang Yang Hu Nian Fu Hai-Lian Lin Bo Jiang Ya-Ying Tian Hong-Yi Yao Li-Pu Deng Xiao-Qing Tang Jie-Can Zhou Jian Tang Xia Xie qiong liu Jing liu Cheng-Yun Dou Rong-Juan Dai Bo Yan Xue-Feng Yang 《World Journal of Clinical Cases》 SCIE 2020年第12期2554-2565,共12页
BACKGROUND In December 2019,an ongoing outbreak of coronavirus disease 2019(COVID-19)was first identified in Wuhan,China.The characteristics of COVID-19 patients treated in local hospitals in Wuhan are not fully repre... BACKGROUND In December 2019,an ongoing outbreak of coronavirus disease 2019(COVID-19)was first identified in Wuhan,China.The characteristics of COVID-19 patients treated in local hospitals in Wuhan are not fully representative of patients outside Wuhan.Therefore,it is highly essential to analyze the epidemiological and clinical characteristics of COVID-19 in areas outside Wuhan or Hubei Province.To date,a limited number of studies have concentrated on the epidemiological and clinical characteristics of COVID-19 patients with different genders,clinical classification,and with or without basic diseases.AIM To study the epidemiological and clinical characteristics of COVID-19 patients in Hengyang(China)and provide a reliable reference for the prevention and control of COVID-19.METHODS From January 16 to March 2,2020,a total of 48 confirmed cases of COVID-19 were reported in Hengyang,and those cases were included in this study.The diagnostic criteria,clinical classification,and discharge standard related to COVID-19 were in line with the Diagnosis and Treatment Protocol for Novel Coronavirus Pneumonia(Trial Version 7)released by National Health Commission and National Administration of Traditional Chinese Medicine.The presence of SARS-CoV-2 in pharyngeal swab specimens was detected by quantitative reverse transcription polymerase chain reaction.All the data were imported into the excel worksheet and statistically analyzed by using SPSS 25.0 software.RESULTS A total of 48 cases of COVID-19 were collected,of which 1 was mild,38 were moderate,and 9 were severe.It was unveiled that there were 31(64.6%)male patients and 17(35.4%)female patients,with a female-to-male ratio of 1.82:1.The range of age of patients with COVID-19 was dominantly 30-49 years old[25(52.1%)of 48],followed by those aged over 60 years old[11(22.9%)].Besides,29.2%(14 of 48)of patients had basic diseases,and 57.2%(8 of 14)of patients with basic diseases were aged over 60 years old.The occupations of 48 COVID-19 patients were mainly farmers working in agricultural production[15(31.5%)of 48],rural migrant workers from Hengyang to Wuhan[15(31.5%)],and service workers operating in the service sector[8(16.7%)].The mean latent period was 6.86±3.57 d,and the median was 7[interquartile range(IQR):4-9]d.The mean time from onset of symptoms to the first physician visit was 3.38±2.98(95%CI:2.58-9.18)d,with a median of 2(IQR:1-5)d,and the mean time from hospital admission to confirmed diagnosis was 2.29±2.11(95%CI:1.18-6.42)d,with a median of 2(IQR:1-3)d.The main symptoms were fever[43(89.6%)of 48],cough and expectoration[41(85.4%)],fatigue[22(45.8%)],and chills[22(45.8%)].Other symptoms included poor appetite[13(27.1%)],sore throat[9(18.8%)],dyspnea[9(18.8%)],diarrhea[7(14.6%)],dizziness[5(10.4%)],headache[5(10.4%)],muscle pain[5(10.4%)],nausea and vomiting[4(8.3%)],hemoptysis[4(8.3%)],and runny nose[1(2.1%)].The numbers of peripheral blood leukocytes,lymphocytes,and eosinophils were significantly reduced in the majority of the patients.The levels of C-reactive protein,fibrinogen,blood glucose,lactate dehydrogenase,Ddimer,alanine aminotransferase(ALT),aspartate aminotransferase(AST),gamma-glutamyl transferase(γ-GT),myoglobin(MB),and creatine kinase(CK)were increased in 64.6%,44.7%,43.2%,37.0%,29.5%,22.9%,20.8%,21.6%,13.6%,and 12.8%of patients,respectively.The incidence of ALT elevation in male patients was remarkably higher than that in females(P<0.01),while the incidences of AST,CK,and blood glucose elevations in severe patients were remarkably higher than those in moderate patients(P<0.05,respectively).Except for the mild patients,chest computed tomography showed characteristic pulmonary lesions.All the patients received antiviral drugs,38(79.2%)accepted traditional Chinese medicine,and 2(4.2%)received treatment of human umbilical-cord mesenchymal stem cells.On March 2,2020,48 patients with COVID-19 were all cured and discharged.CONCLUSION Based on our results,patients with COVID-19 often have multiple organ dysfunction or damage.The incidences of ALT elevation in males,and AST,CK,and blood glucose elevations in severe patients are remarkably higher. 展开更多
关键词 Novel coronavirus pneumonia COVID-19 SARS-CoV-2 EPIDEMIOLOGY Hengyang Coronavirus disease 2019
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Analysis of Status of Photovoltaic and Wind Power Abandoned in China 被引量:6
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作者 Shimin Li Jing Wang +3 位作者 qiong liu Lingyan Li Yaping Hua Wei liu 《Journal of Power and Energy Engineering》 2017年第1期91-100,共10页
It was reported that the total installed capacity of photovoltaic power in China has reached 43.5 GW [1] at the end of 2015. With the vast territory and abundant solar energy resources in western part of China, more t... It was reported that the total installed capacity of photovoltaic power in China has reached 43.5 GW [1] at the end of 2015. With the vast territory and abundant solar energy resources in western part of China, more than 50 percent of photovoltaic power stations and wind farms were built there. In recent years, influenced by such factors as rapid growth in installed capacity of PV power stations and wind farms, power generation districts far away from power consumption load as well as its mismatch in transmission line, the phenomenon of abandoning solar and wind power has already restricted severely the normal operation of photovoltaic and wind power generation. It has greatly reduced the enthusiasm of the investors and constructors for investing and building power stations. This paper, based on the status in quo of power generation market and power supply in China, analyzes multi-aspect reasons for the phenomenon of abandoning solar and wind power and discusses their solutions. 展开更多
关键词 WIND and Solar POWER Abandoned RENEWABLE Energy POWER CONSUMPTION
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