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Predictive value of diaphragm ultrasound for mechanical ventilation outcome in patients with acute exacerbation of chronic obstructive pulmonary disease 被引量:1
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作者 Lei-Lei Qu Wen-Ping Zhao +1 位作者 Ji-Ping Li Wei Zhang 《World Journal of Clinical Cases》 SCIE 2024年第26期5893-5900,共8页
BACKGROUND Acute exacerbation of chronic obstructive pulmonary disease(AECOPD)is often combined with respiratory failure,which increases the patient's morbidity and mortality.Diaphragm ultrasound(DUS)has developed... BACKGROUND Acute exacerbation of chronic obstructive pulmonary disease(AECOPD)is often combined with respiratory failure,which increases the patient's morbidity and mortality.Diaphragm ultrasound(DUS)has developed rapidly in the field of critical care in recent years.Studies with DUS monitoring diaphragm-related rapid shallow breathing index have demonstrated important results in guiding intensive care unit patients out of the ventilator.Early prediction of the indications for withdrawal of non-invasive ventilator and early evaluation of patients to avoid or reduce disease progression are very important.AIM To explore the predictive value of DUS indexes for non-invasive ventilation outcome in patients with AECOPD.METHODS Ninety-four patients with AECOPD who received mechanical ventilation in our hospital from January 2022 to December 2023 were retrospectively analyzed,and they were divided into a successful ventilation group(68 cases)and a failed ventilation group(26 cases)according to the outcome of ventilation.The clinical data of patients with successful and failed noninvasive ventilation were compared,and the independent predictors of noninvasive ventilation outcomes in AECOPD patients were identified by multivariate logistic regression analysis.RESULTS There were no significant differences in gender,age,body mass index,complications,systolic pressure,heart rate,mean arterial pressure,respiratory rate,oxygen saturation,partial pressure of oxygen,oxygenation index,or time of inspiration between patients with successful and failed mechanical ventilation(P>0.05).The patients with successful noninvasive ventilation had shorter hospital stays and lower partial pressure of carbon dioxide(PaCO_(2))than those with failed treatment,while potential of hydrogen(pH),diaphragm thickening fraction(DTF),diaphragm activity,and diaphragm movement time were significantly higher than those with failed treatment(P<0.05).pH[odds ratio(OR)=0.005,P<0.05],PaCO_(2)(OR=0.430,P<0.05),and DTF(OR=0.570,P<0.05)were identified to be independent factors influencing the outcome of mechanical ventilation in AECOPD patients.CONCLUSION The DUS index DTF can better predict the outcome of non-invasive ventilation in AECOPD patients. 展开更多
关键词 Diaphragm ultrasound Mechanical ventilation Acute exacerbation of chronic obstructive pulmonary disease Predictive value Diaphragm thickening fraction Diaphragm activity
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Effect of Biostimulants Based on Natural Products on the Growth and Nutritional Value of Bean (Phaseolus vulgaris L.)
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作者 Aimé Giresse Tzeuton Flore Eliane Eyenga +10 位作者 Arouna Meshuneke Gaston Mbang Elock Fabrice Damien Wassom Walter Jospin Timma Kom Marie Paule Djam Kengoum Erica Cabrelle Damtse Damtse Landry Silatsa Fotsing William Asah Che Marlyne Josephine Mananga Nicolas Niemenak Cécile Annie Ewané 《American Journal of Plant Sciences》 CAS 2024年第7期492-518,共27页
Beans (Phaseolus vulgaris L.) are widely grown in Cameroon and play a key role in the fight against food insecurity, malnutrition and poverty. However, its cultivation encounters problems due to abiotic and biotic str... Beans (Phaseolus vulgaris L.) are widely grown in Cameroon and play a key role in the fight against food insecurity, malnutrition and poverty. However, its cultivation encounters problems due to abiotic and biotic stresses, which leads to the use of synthetic fertilizers and pesticides, which cause significant damage to the environment and human health due to the presence of synthetics residues in the seeds, pods and in the leaves that are eaten. Promoting the use of natural products is becoming a necessity for organic and eco-responsible agriculture that limits contamination problems and improves people’s purchasing power. This study aims to assess the effect of biostimulants based on natural products on the growth and nutritional value of common bean (Phaseolus vulgaris L.). Bean seedlings from white variety (MEX-142) and red variety (DOR-701) were treated every seven days in the field from their pre-emergence, emergence and growth to their maturation under a randomized block experimental design. Six treatments and three repetitions with the biostimulants based on natural products and controls were thus performed and the agromorphological parameters were measured. After 120 days, the contents of growth biomarkers and defense-related enzymes were evaluated in leaves, while the contents of macromolecules, minerals and antinutrients were evaluated in seeds. These biostimulants significantly increased (P P < 0.0001) of antinutrients including oxalates, phytates, tannins and saponins in seeds compared to controls (T+ and T−). Treatment with biostimulants, in particular BS4, improves the performance of bean plants in the field as well as the biofortification of seeds regardless of the variety. 展开更多
关键词 phaseolus vulgaris L. Biostimulants BIOFORTIFICATION Growth and Defense Biomarkers Nutritional value
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Decision Making Based on Valued Fuzzy Superhypergraphs
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作者 Mohammad Hamidi Florentin Smarandache Mohadeseh Taghinezhad 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1907-1923,共17页
This paper explores the defects in fuzzy (hyper) graphs (as complex (hyper) networks) and extends the fuzzy(hyper) graphs to fuzzy (quasi) superhypergraphs as a new concept.We have modeled the fuzzy superhypergraphsas... This paper explores the defects in fuzzy (hyper) graphs (as complex (hyper) networks) and extends the fuzzy(hyper) graphs to fuzzy (quasi) superhypergraphs as a new concept.We have modeled the fuzzy superhypergraphsas complex superhypernetworks in order to make a relation between labeled objects in the form of details andgeneralities. Indeed, the structure of fuzzy (quasi) superhypergraphs collects groups of labeled objects and analyzesthem in the form of the part to part of objects, the part of objects to the whole group of objects, and the whole tothe whole group of objects at the same time.We have investigated the properties of fuzzy (quasi) superhypergraphsbased on any positive real number as valued fuzzy (quasi) superhypergraphs, considering the complement of valuedfuzzy (quasi) superhypergraphs, the notation of isomorphism of valued fuzzy (quasi) superhypergraphs based onthe permutations, and we have presented the isomorphic conditions of (self complemented) valued fuzzy (quasi)superhypergraphs. The concept of impact membership value of fuzzy (quasi) superhypergraphs is introducedin this study and it is applied in designing the real problem in the real world. Finally, the problem of businesssuperhypernetworks is presented as an application of fuzzy valued quasi superhypergraphs in the real world. 展开更多
关键词 (Quasi)superhypergraph valued fuzzy(quasi)superhypergraph impact membership value complex superhypernetwork
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A Value for Games Defined on Graphs
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作者 Néstor Bravo 《Applied Mathematics》 2024年第5期331-348,共18页
Given a graph g=( V,A ) , we define a space of subgraphs M with the binary operation of union and the unique decomposition property into blocks. This space allows us to discuss a notion of minimal subgraphs (minimal c... Given a graph g=( V,A ) , we define a space of subgraphs M with the binary operation of union and the unique decomposition property into blocks. This space allows us to discuss a notion of minimal subgraphs (minimal coalitions) that are of interest for the game. Additionally, a partition of the game is defined in terms of the gain of each block, and subsequently, a solution to the game is defined based on distributing to each player (node and edge) present in each block a payment proportional to their contribution to the coalition. 展开更多
关键词 Graph Theory values for Graphs Cooperation Games Potential Function
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Effect of FeSi additive in dual-chamber sample cup on thermal analysis characteristic values and vermiculating rate of compacted graphite iron
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作者 De-quan Shi Ze-yu Liu +1 位作者 Gui-li Gao Yi-cheng Feng 《China Foundry》 SCIE EI CAS CSCD 2024年第1期91-100,共10页
Thermal analysis plays a key role in the online inspection of molten iron quality.Different solidification process of molten iron can be reflected by thermal analysis curves,and silicon is one of important elements af... Thermal analysis plays a key role in the online inspection of molten iron quality.Different solidification process of molten iron can be reflected by thermal analysis curves,and silicon is one of important elements affecting the solidification of molten iron.In this study,FeSi75 was added in one chamber of the dual-chamber sample cup,and the influences of FeSi75 additive on the characteristic values of thermal analysis curves and vermiculating rate were investigated.The results show that with the increase of FeSi75,the start temperature of austenite formation TALfirstly decreases and then increases,but the start temperature of eutectic growth TSEF,the lowest eutectic temperature TEU,temperature at maximum eutectic reaction rate TEM,and highest eutectic temperature TERkeep always an increase.The temperature at final solidification point TEShas little change.The FeSi75 additive has different influences on the vermiculating rate of molten iron with different vermiculation,and the vermiculating rate increases for lower vermiculation molten iron while decreases for higher one.According to the thermal analysis curves obtained by a dual-chamber sample cup with 0.30wt.%FeSi75 additive in one chamber,the vermiculating rate of molten iron can be evaluated by comparing the characteristic values of these curves.The time differenceΔtERcorresponding to the highest eutectic temperature TERhas a closer relationship with the vermiculating rate,and a parabolic regression curve between the time differenceΔtERand vermiculating rateηhas been obtained within the range of 65%to 95%,which is suitable for the qualified melt. 展开更多
关键词 FeSi75 additive characteristic value vermiculating rate thermal analysis compacted graphite iron
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Spatio-temporal evolution and topographic gradient effect of land use and ecosystem service value in the Lhasa River Basin
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作者 ZHOU Jianwei FENG Bin +8 位作者 WU Hua XU Tong CHEN Linna ZHAO Xinyong GUO Qiyun LI Jiatong ZHANG Chenguang ZHU Kangcheng KONG Yuzhong 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2059-2074,共16页
The Lhasa River Basin forms an essential human settlement area in the southern part of the Qinghai-Tibet Plateau.This study employed ecosystem service value(ESV)evaluation model,terrain gradient grading,and Geodetecto... The Lhasa River Basin forms an essential human settlement area in the southern part of the Qinghai-Tibet Plateau.This study employed ecosystem service value(ESV)evaluation model,terrain gradient grading,and Geodetector to analyze land use and ESV in the Lhasa River Basin from 1985 to 2020.The findings reveal that:(1)From 1985 to 2020,grassland was the dominant land use.There was a trend of grassland reduction and the expansion of other land types.(2)ESV has increased over the research period(with a total increase of 0.84%),with higher values in the southeast and lower values in the northwest.Grassland contributed the most to ESV,and climate regulation and hydrological regulation were the ecosystem services that contribute the most to ESV.(3)Natural factors like NDVI and altitude,as well as economic factors like population density and distance from roads,influenced the spatial differentiation of ESV,the explanatory power of NDVI reached up to 0.47.The interaction between factors had a greater impact than individual factors.These research results can provide theoretical support for national spatial planning and ecological environment protection in the Lhasa River Basin and other similar areas. 展开更多
关键词 Ecosystem services value Land use Terrain gradient effect Lhasa River Basin Driving factors
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The Maximum and Minimum Value of Exponential RandićIndices of Quasi-Tree Graph
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作者 Lei Qiu Xijie Ruan Yan Zhu 《Journal of Applied Mathematics and Physics》 2024年第5期1804-1818,共15页
The exponential Randić index has important applications in the fields of biology and chemistry. The exponential Randić index of a graph G is defined as the sum of the weights e 1 d( u )d( v ) of all edges uv of G, whe... The exponential Randić index has important applications in the fields of biology and chemistry. The exponential Randić index of a graph G is defined as the sum of the weights e 1 d( u )d( v ) of all edges uv of G, where d( u ) denotes the degree of a vertex u in G. The paper mainly provides the upper and lower bounds of the exponential Randić index in quasi-tree graphs, and characterizes the extremal graphs when the bounds are achieved. 展开更多
关键词 Exponential Randić Index Quasi-Tree Graph Extremal value Extremal Graphs
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2024 PH Value春夏针织展 在春天里感受新质针织力量
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作者 梁龙 《中国纺织》 2024年第3期65-66,共2页
150余家针织企业参展,10000平方米盛大规模,三天展会,2024 PH Value春夏针织展,人气爆满,现场合作签约不断,很多参展商都表示收到了意向客户的橄榄枝,一张张笑脸的背后,是展会成功的见证。不仅商贸对接实效显著,展会期间,行业同仁面对... 150余家针织企业参展,10000平方米盛大规模,三天展会,2024 PH Value春夏针织展,人气爆满,现场合作签约不断,很多参展商都表示收到了意向客户的橄榄枝,一张张笑脸的背后,是展会成功的见证。不仅商贸对接实效显著,展会期间,行业同仁面对面的交流及各种论坛活动的举办,都让针织人在这个春光里感受到产业孕育的希望。 展开更多
关键词 针织企业 参展商 行业同仁 ph 展会 面对面
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Influence of pH value and chelating reagent on performance of Li_3V_2(PO_4)3/C cathode material 被引量:2
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作者 向伟 唐艳 +4 位作者 王雁英 钟本和 方为茂 刘恒 郭孝东 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第5期1395-1402,共8页
The Li3V2(PO4)3/C composite cathode material was synthesized via sol-gel method using three different chelating agents (citric acid, salicylic acid and polyacrylic acid) at pH value of 3 or 7. The crystal structur... The Li3V2(PO4)3/C composite cathode material was synthesized via sol-gel method using three different chelating agents (citric acid, salicylic acid and polyacrylic acid) at pH value of 3 or 7. The crystal structure, morphology, specific surface area and electrochemical performance of the prepared samples were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge/discharge test. The results show that the effects of pH value on the performance of the prepared materials are greatly related to the chelating agents. With salicylic acid or polyacrylic acid as the chelating reagent, the structure, morphology and electrochemical performance of the samples are greatly influenced by the pH values. However, the structure of the materials with citric acid as the chelating agent does not change as pH value changes, and the materials own uniform particle size distribution and good electrochemical performance. It delivers an initial discharge capacity of 113.58 mA·h/g at 10C, remaining as high as 108.48 mA·h/g after 900 cycles, with a capacity retention of 95.51%. 展开更多
关键词 Li3V2(PO4)3 cathode material sol-gel method chelating agents ph value
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Influence of pH Value on Photocatalytic Activity of Bi4Ti3O12 Crystals Obtained by Hydrothermal Method 被引量:1
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作者 林雪 宫宇宁 +2 位作者 张耀丹 闫永胜 关庆丰 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第2期209-213,I0004,共6页
Bi4Ti3O12 (BIT) crystals were controllably synthesized via a facile hydrothermal process without adding any surfactant or template. The morphologies of BIT with nanosphere, nanoplate, nanobelt, and nanosheet can be ... Bi4Ti3O12 (BIT) crystals were controllably synthesized via a facile hydrothermal process without adding any surfactant or template. The morphologies of BIT with nanosphere, nanoplate, nanobelt, and nanosheet can be selectively obtained by adjusting the pH value of the reactant. The formation mechanisms of these distinctive morphologies were then discussed based on the structural analysis of samples obtained at different pH values. BIT sample prepared at pH=1 showed the highest photocatalytic activity under visible light irradiation. The photocatalytic activities difference for the BIT samples synthesized at different pH values was studied based on their shape, size, and the variation of local structure. 展开更多
关键词 phOTOCATALYSIS BI4TI3O12 ph value Local structure
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基于Valued ERGMs模型的核心技术网络成长机制研究——以量子计算领域为例 被引量:2
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作者 任海英 李真 《科技进步与对策》 CSSCI 北大核心 2024年第4期1-11,共11页
对核心技术网络及其成长机制的研究有助于梳理核心技术之间的依赖和促进关系,为研究核心技术演化提供新的理论视角和方法。以技术演化相关理论为基础,归纳核心技术网络成长的影响因素,基于量子计算领域专利数据,识别以技术概念和技术关... 对核心技术网络及其成长机制的研究有助于梳理核心技术之间的依赖和促进关系,为研究核心技术演化提供新的理论视角和方法。以技术演化相关理论为基础,归纳核心技术网络成长的影响因素,基于量子计算领域专利数据,识别以技术概念和技术关系为基础的量子计算领域核心技术网络,并基于Valued ERGMs模型构建核心技术网络成长机制模型。结果表明,技术要素中心性、专利技术研发能力、与TRIZ进化法则匹配程度以及技术要素同配性对核心技术网络成长具有正向促进作用;在技术路径方面,核心技术网络成长受到技术要素路径依赖性和技术突破的双重影响。最后,根据量子计算领域核心技术网络成长机制的实证研究结果,从技术研发层面、企业层面、政府层面为相关领域技术发展提出策略建议。 展开更多
关键词 技术演化 核心技术网络 技术网络成长机制 valued ERGMs模型 量子计算
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Correlation Analysis of SPAD Value with Chlorophyll Content and Economic Yield Traits of Brassica napus L. 被引量:6
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作者 高建芹 浦惠明 +4 位作者 张洁夫 龙卫华 陈锋 周晓婴 张维 《Agricultural Science & Technology》 CAS 2013年第10期1421-1428,共8页
[Objective] The aim was to compare differences of SPAD value, chloro- phyll content, agronomic characters, economic characters and yield traits to analyze correlation of SPAD value with other indices and establish reg... [Objective] The aim was to compare differences of SPAD value, chloro- phyll content, agronomic characters, economic characters and yield traits to analyze correlation of SPAD value with other indices and establish regression functions. [Method] Based on 34 Brassica napus L. varieties, SPAD value, chlorophyll content, agronomic characters, economic characters and yield traits were measured and re- gression functions were established according to correlations. [Result] SPAD value, chlorophyll content, agronomic and economic characters and yield traits all achieved significant level in differences among 34 varieties. Specifically, SPAD value was of extremely significant correlation with chlorophyll a and b, total chlorophyll and carotenoid, and the correlation from high to low was chl-b〉chl-z〉chl-a〉chl-x. SPAD value was of significantly positive correlation with total pod number per plant, plant height, seed number per pod, yield per plant and harvest yield, and of insignificant correlation with branch point height, effective branch number, pod density of main stem, and pod length. [Conclusion] It is simple and rapid to predict chlorophyll con- tent, economic characters and yields of Brassica napus L. with SPAD value and re- gression functions. 展开更多
关键词 Brassica napus L. SPAD value Chlorophyll content Economic yield Correlation analysis
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弹性退休制度下谁更愿意延迟退休?——基于Option Value模型的微观模拟
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作者 郭秀云 李悦心 《人口与发展》 CSSCI 北大核心 2024年第4期132-144,共13页
人口老龄化背景下延迟退休年龄、建立弹性退休制度是大势所趋。养老金激励是弹性退休制度的重要内容。建立期权价值模型和养老金给付及奖惩因子模型,基于中国家庭收入调查项目(CHIP2018)的数据,对不同特征人群的养老金峰值、期权价值、... 人口老龄化背景下延迟退休年龄、建立弹性退休制度是大势所趋。养老金激励是弹性退休制度的重要内容。建立期权价值模型和养老金给付及奖惩因子模型,基于中国家庭收入调查项目(CHIP2018)的数据,对不同特征人群的养老金峰值、期权价值、内部报酬率进行模拟。研究发现:养老金总财富随退休年龄“先增后减”,男性的峰值年龄早于女性;引入养老金“奖惩”机制有助于提高最优退休年龄,激励劳动者延迟退休;考虑闲暇偏好的异质性,男性参保者更倾向于早退休,而女性参保者特别是女性较高收入群体更愿意延迟退休;厌恶风险的参保者更有可能选择早退休。建议尽早建立弹性退休年龄政策体系,增加劳动者的选择权和制度灵活性;引入精算调节因子构建养老金奖惩机制,完善养老保险待遇计发办法。 展开更多
关键词 延迟退休 养老金财富 Option value模型
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Adsorption Kinetics of NH_4^+ by Purple Soils with Different pH Values
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作者 张迪男 蒋先军 《Agricultural Science & Technology》 CAS 2015年第7期1336-1339,1370,共5页
Ammonium adsorption and desorption properties by purple soils with dif- ferent pH were studied. The results showed that the adsorption and desorption amounts of NH4+ by purple soils increased with the increase of NH4... Ammonium adsorption and desorption properties by purple soils with dif- ferent pH were studied. The results showed that the adsorption and desorption amounts of NH4+ by purple soils increased with the increase of NH4+ concentration, regardless of soil pH values; the largest adsorption and desorption amounts of NH4+ by purple soil at pH 6.0 were 10.3 and 7.96 mg/g, respectively; the largest adsorp- tion and desorption amounts of NH4+ by purple soil at pH 7.2 were 12.8 and 4.62 mg/g, respectively; the largest adsorption and desorption amounts of NH4+ by purple soil at pH 8.0 were 13.5 and 2.23 mg/g, respectively. The isothermal adsorption ki- netics of NH4+ by purple soils fits the Freundlich equation best (R〉0.95). This study shows that the adsorption of NH4+ by purple soils with different pH values is multi- molecular layer uneven surface adsorption. 展开更多
关键词 NHZ ADSORPTION DESORPTION ph value Isothermal adsorption equation
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Effect of pH values on extracellular protein and polysaccharide secretions of Acidithiobacillus ferrooxidans during chalcopyrite bioleaching 被引量:6
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作者 余肇璟 余润兰 +4 位作者 刘阿娟 刘晶 曾伟民 刘学端 邱冠周 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第2期406-412,共7页
The effect of pH values on the extracellular protein and polysaccharide secretions of Acidithiobacillus ferrooxidans was comparatively investigated in different phases of bacterial growth during chalcopyrite bioleachi... The effect of pH values on the extracellular protein and polysaccharide secretions of Acidithiobacillus ferrooxidans was comparatively investigated in different phases of bacterial growth during chalcopyrite bioleaching. The results indicate that the extracellular protein is always more than the extracellular polysaccharide secreted by attached cells on the chalcopyrite, on the contrary, and is always less than the extracellular polysaccharide secreted by free cells in the solution at bacterial adaptive phase, logarithmic phase and stationary phase whenever pH value is at 1.0, 1.5, 2.0 or 2.5; free cells are mainly through the secretion of extracellular polysaccharide rather than the extracellular protein to fight against disadvantageous solution environment, such as high concentration of metal ions and unsuitable pH solution; both amounts of polysaccharide and protein secreted by attached cells are mainly positively related to the solution acidity rather than the total concentration of soluble metal ions. The experimental results imply that bacteria are mainly through secreting more extracellular polysaccharide to fight against disadvantageous environment and the extracellular protein perhaps plays an important role in oxidation?reduction reactions in the bioleaching system. 展开更多
关键词 extracellular protein Acidithiobacillus ferrooxidans CHALCOPYRITE BIOLEACHING ph value
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Corrosion behaviour of die-cast AZ91D magnesium alloys in sodium sulphate solutions with different pH values 被引量:5
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作者 田赟 杨丽景 +4 位作者 李艳芳 卫英慧 侯利锋 李永刚 Ri-Ichi MURAKAMI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期912-920,共9页
The corrosion behaviours of die-cast AZ91D magnesium alloys were investigated in 0.1 mol/L sodium sulphate (Na 2 SO 4 ) solutions with different pH values. The corrosion rates, morphologies, and compositions of the ... The corrosion behaviours of die-cast AZ91D magnesium alloys were investigated in 0.1 mol/L sodium sulphate (Na 2 SO 4 ) solutions with different pH values. The corrosion rates, morphologies, and compositions of the corrosion products were studied by means of scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffractometry (XRD). The results indicate that the order of corrosion rates in Na 2 SO 4 solutions with various pH values is pH 2pH 4pH 7pH 9pH 12. The corrosion rates in acidic solutions are higher than those in alkaline solutions, and the corrosion products are mainly magnesium hydroxide (Mg(OH) 2 ) and hydrated sulphate pickeringite (MgAl 2 (SO 4 ) 4 ·22H 2 O). The results also indicate that the solution pH can influence the corrosion rate and morphology of corrosion products. Chloride ions and sulphate ions have different pitting initiation time. 展开更多
关键词 magnesium alloy CORROSION sodium sulphate ph value
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Clinical Application and Pharmaceutical Values of Levant Cotton Root
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作者 郭宝生 王凯辉 +3 位作者 刘素恩 赵存鹏 王兆晓 耿军义 《Agricultural Science & Technology》 CAS 2014年第2期248-250,共3页
Levant cotton root is a folk traditional herb with a long history in China. This article gave a brief introduction on recent research work related to main com- position, pharmacologic effect and clinical application o... Levant cotton root is a folk traditional herb with a long history in China. This article gave a brief introduction on recent research work related to main com- position, pharmacologic effect and clinical application of levant cotton root and pro- posed existing problems and countermeasures for pharmaceutical industrialization. 展开更多
关键词 Levant Cotton Root pharmaceutical values Clinical application
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One-pot synthesis of ordered mesoporous Cu-KIT-6 and its improved catalytic behavior for the epoxidation of styrene:Effects of the pH value of the initial gel 被引量:3
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作者 李白滔 罗歆 +2 位作者 黄静 王秀军 梁振兴 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第3期518-528,共11页
The heterogeneously copper-catalyzed oxidative cleavage of styrene was studied using copper-doped mesoporous KIT-6(CU-KIT-6_x) prepared via pH adjustment(where x is the pH:1.43,2.27,3.78,3.97,4.24 or 6.62).Variat... The heterogeneously copper-catalyzed oxidative cleavage of styrene was studied using copper-doped mesoporous KIT-6(CU-KIT-6_x) prepared via pH adjustment(where x is the pH:1.43,2.27,3.78,3.97,4.24 or 6.62).Variations in the catalyst structure and morphology with pH values were characterized by X-ray power diffraction,nitrogen adsorption-desorption analysis,transmission electron microscopy and X-ray photoelectron spectroscopy.As the pH value applied during the initial synthesis,the resulting Cu-KIT-6_x exhibited different structural,textural and surface characteristics,especially in terms of specific copper species and copper content At a pH value of 3.78,approximately 4.6 wt%copper(Ⅱ) was successfully incorporated into the framework of the initial KIT-6,in the form of-Cu-O-Si- groups.The catalytic performance of each catalyst was evaluated by following the epoxidation of styrene,employing tert-butyl hydroperoxide as the oxidant and CH_3CN as the solvent.A significant styrene conversion of 43.5%with 86.6%selectivity for the desired styrene epoxide was obtained over the Cu-KIT-63.78.A higher Cu content,an ordered cubic laid mesoporous architecture and various specific textural characteristics all combined to endow the Cu-KIT-63.78 with high catalytic activity and good stability. 展开更多
关键词 Mesoporous material KIT-6 Styrene epoxidation ph-adjusting
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The Distribution Characteristics of Soil pH Values of Tobacco-growing Areas in Dali City and Its Correlation with Soil Nutrients 被引量:1
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作者 杨春文 赵宇 +5 位作者 王新中 杨成伟 杨志娟 户艳霞 孙军伟 王德勋 《Agricultural Science & Technology》 CAS 2015年第5期951-953,972,共4页
[Objective] The aim was to study the distribution characteristics of soil pH values and its correlation with soil nutrients in tobacco-growing areas. [Method] Soil nutrients of 43 samples from tobacco-growing areas in... [Objective] The aim was to study the distribution characteristics of soil pH values and its correlation with soil nutrients in tobacco-growing areas. [Method] Soil nutrients of 43 samples from tobacco-growing areas in Dali City were analyzed.[Results] The results showed that average pH value of tobacco-planting soil in Dali City was 6.52, soil samples which suited for flue-cured tobacco cultivation accounted for 72.09% of total soil samples. In four soil types of tobacco-growing areas, the pH values in a descending order were as follows: alluvial soil〉 paddy soil 〉purple soil〉 red soil. At the altitude range of 1 780-2 200 m, soil pH values showed a gradual decreasing trend. The average contents of soil organic matters were relatively abundant and generally suited for high-quality tobacco cultivation; the average contents of soil alkali-hydrolyzable nitrogen, available phosphorus, exchangeable calcium and exchangeable magnesium were generally at medium and abundant level, however,their rations under the medium level in some tobacco-growing areas were 6.98%,11.63%, 2.33% and 4.65%, respectively; moreover, soil with lower available potassium contents occupied a large proportion, namely 58.14%. [Conclusion] Soil pH values had significant correlation with exchangeable magnesium and exchangeable magnesium, however, they had no significant correlation with other soil nutrients. 展开更多
关键词 Tobacco-growing areas SOIL ph values Soil nutrients Correlation analysis
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Advances in Pharmaceutical and Ecological Value of Sagina japonica(Sw.) Ohwi
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作者 王欢 胡静波 +6 位作者 黄海艳 徐文进 尚姣 张峡 马亚荣 巩江 倪士峰 《Agricultural Science & Technology》 CAS 2015年第5期1043-1047,共5页
Sagina japonica(Sw.) Ohwi is a traditional medicinal herb for the treatment of lacquer dermatitis, and its medicinal and ecological value needs to be further developed. Based on broad literature search, this paper s... Sagina japonica(Sw.) Ohwi is a traditional medicinal herb for the treatment of lacquer dermatitis, and its medicinal and ecological value needs to be further developed. Based on broad literature search, this paper summarized the identification, composition, pharmacology, clinical applications, ecological value, and cultivation technologies of S. japonica(Sw.) Ohwi, aiming at providing scientific information for further research and development of S. japonica(Sw.) Ohwi. 展开更多
关键词 Sagina japonica (Sw.) Ohwi Identification Composition phARMACOLOGY Clinical applications Ecological value Cultivation technologies
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