期刊文献+
共找到37篇文章
< 1 2 >
每页显示 20 50 100
Graphene effectively activating "dead" water molecules between manganese dioxide layers in potassium-ion battery
1
作者 Xinhai Wang Wensheng Yang +5 位作者 Shengshang Lu Shangshu Peng Tong Guo quan xie Qingquan Xiao Yunjun Ruan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期306-315,I0008,共11页
Aqueous potassium-ion batteries(APIBs),recognized as safe and reliable new energy devices,are considered as one of the alternatives to traditional batteries.Layered MnO_(2),serving as the main cathode,exhibits a lower... Aqueous potassium-ion batteries(APIBs),recognized as safe and reliable new energy devices,are considered as one of the alternatives to traditional batteries.Layered MnO_(2),serving as the main cathode,exhibits a lower specific capacity in aqueous electrolytes compared to organic systems and operates through a different reaction mechanism.The application of highly conductive graphene may effectively enhance the capacity of APIBs but could complicate the potassium storage environment.In this study,a MnO_(2) cathode pre-intercalated with K~+ions and grown on graphene(KMO@rGO) was developed using the microwave hydrothermal method for APIBs.KMO@rGO achieved a specific capacity of 90 mA h g^(-1) at a current density of 0.1 A g^(-1),maintaining a capacity retention rate of>90% after 5000 cycles at 5 A g^(-1).In-situ and exsitu characterization techniques revealed the energy-storage mechanism of KMO@rGO:layered MnO_(2)traps a large amount of "dead" water molecules during K~+ions removal.However,the introduction of graphene enables these water molecules to escape during K~+ ions insertion at the cathode.The galvanostatic intermittent titration technique and density functional theory confirmed that KMO@rGO has a higher K~+ions migration rate than MnO_(2).Therefore,the capacity of this cathode depends on the interaction between dead water and K~+ions during the energy-storage reaction.The optimal structural alignment between layered MnO_(2) and graphene allows electrons to easily flow into the external circuit.Rapid charge compensation forces numerous low-solvent K~+ions to displace interlayer dead water,enhancing the capacity.This unique reaction mechanism is unprecedented in other aqueous battery studies. 展开更多
关键词 GRAPHENE K-ion batteries Mn-based layered oxide Water molecules Density functional theory
下载PDF
云克和玻璃酸钠治疗膝骨关节炎合并滑膜炎的疗效观察 被引量:13
2
作者 周影 潘卫民 +6 位作者 孙雯 王超群 严娟娟 谢权 黄莹 肖欢 颜卫文 《中国现代医学杂志》 CAS 2019年第5期103-107,共5页
目的探讨与观察云克和玻璃酸钠治疗膝骨关节炎(KOA)合并滑膜炎的疗效。方法选取2014年6月—2017年2月海南医学院第一附属医院诊治的KOA合并滑膜炎患者60例。根据随机数字表法分为观察组和对照组,每组30例,对照组给予玻璃酸钠治疗,观察... 目的探讨与观察云克和玻璃酸钠治疗膝骨关节炎(KOA)合并滑膜炎的疗效。方法选取2014年6月—2017年2月海南医学院第一附属医院诊治的KOA合并滑膜炎患者60例。根据随机数字表法分为观察组和对照组,每组30例,对照组给予玻璃酸钠治疗,观察组在对照组治疗的基础给予云克治疗,都治疗观察两疗程。结果观察组与对照组总有效率为96.7%和76.7%,两组比较差异有统计学意义(P <0.05)。两组治疗后的VAS评分降低,Lysholm评分升高,与治疗前比较差异有统计学意义(P <0.05),治疗后观察组与对照组比较差异有统计学意义(P <0.05)。治疗后观察组与对照组的CRP分别为(4.76±3.42)和(11.14±3.19)mg/L,均低于治疗前的(27.44±8.24)和(26.98±7.13)mg/L,差异有统计学意义(P <0.05),观察组与对照组比较差异有统计学意义(P <0.05)。观察组与对照组治疗后的外周血CD3^+值和CD3^+CD8^+值均高于治疗前,差异有统计学意义(P <0.05),观察组与对照组比较差异有统计学意义(P <0.05)。结论云克和玻璃酸钠治疗KOA合并滑膜炎能促进机体免疫功能的恢复,快速缓解和改善膝关节疼痛,促进CRP降低,从而提高治疗疗效。 展开更多
关键词 膝骨关节炎 滑膜炎 云克 玻璃酸钠 免疫功能
下载PDF
大连碧流河水库及河流典型抗生素污染和分布特征研究 被引量:9
3
作者 董莞莞 何欣 +3 位作者 郑洪波 张瑛 全燮 穆海林 《大连理工大学学报》 EI CAS CSCD 北大核心 2020年第2期119-127,共9页
采用固相萃取和LC-MS/MS方法分析了23种抗生素在碧流河水库及其入库河流水体和沉积物中的污染和分布特征.结果表明,碧流河水库及其入库河流均存在抗生素污染.碧流河水库及其入库河流水体中共检出10种抗生素,检出率1%~22%,平均浓度0.046~... 采用固相萃取和LC-MS/MS方法分析了23种抗生素在碧流河水库及其入库河流水体和沉积物中的污染和分布特征.结果表明,碧流河水库及其入库河流均存在抗生素污染.碧流河水库及其入库河流水体中共检出10种抗生素,检出率1%~22%,平均浓度0.046~6.1 ng·L^-1.依诺沙星、氯霉素、氟苯尼考是水体中的优势污染物.沉积物中共检出9种抗生素,检出率1.5%~32%,平均浓度0.014~7.1 ng·g^-1.磺胺嘧啶、磺胺甲噁唑和林可霉素是沉积物中的优势污染物.与国内外其他饮用水源相比,碧流河水库及其入库河流的抗生素浓度检出水平较低.碧流河、卧龙泉河是碧流河水库抗生素污染的主要来源.抗生素的浓度分布特征与流域人口分布、季节变化呈现相关性.生态风险评价结果显示,依诺沙星处于高风险,是该区域水环境中抗生素生态风险首要来源. 展开更多
关键词 抗生素 饮用水源 沉积物 分布特征 碧流河水库
下载PDF
Cu掺杂MIL-88B-Fe活化双氧水降解有机污染物性能研究 被引量:4
4
作者 高聪 全燮 陈硕 《大连理工大学学报》 EI CAS CSCD 北大核心 2019年第1期1-7,共7页
非均相类芬顿反应是一种去除水中难降解有机污染物的有效方法,但受限于Fe(Ⅲ)向Fe(Ⅱ)转换速率较慢,非均相类芬顿催化剂活性普遍偏低.通过溶剂热法制备了高活性Cu掺杂MIL-88B-Fe非均相类芬顿催化剂.以苯酚作为目标污染物,研究了Cu掺杂量... 非均相类芬顿反应是一种去除水中难降解有机污染物的有效方法,但受限于Fe(Ⅲ)向Fe(Ⅱ)转换速率较慢,非均相类芬顿催化剂活性普遍偏低.通过溶剂热法制备了高活性Cu掺杂MIL-88B-Fe非均相类芬顿催化剂.以苯酚作为目标污染物,研究了Cu掺杂量对MIL-88B-Fe催化性能的影响.结果表明,掺杂Cu可以提高MIL-88B-Fe的催化性能,MIL-88B-Fe0.6Cu0.4的催化活性最高,其降解苯酚动力学常数是未掺杂MIL-88B-Fe的1.6倍,并且比一些常见的非均相类芬顿催化剂(Fe2O3、α-FeOOH及FeBiO3)高3个数量级.X射线光电子能谱(XPS)及电化学表征结果表明:Cu的掺杂可以加快催化剂中电子传递,促进催化剂中Fe(Ⅲ)/Fe(Ⅱ)氧化还原循环,从而提高MIL-88B-Fe催化效率. 展开更多
关键词 非均相类芬顿反应 CU掺杂 MIL-88B-Fe 电子传递 有机污染物
下载PDF
固定床中γ-Al2O3负载金属氧化物催化臭氧氧化研究 被引量:2
5
作者 齐文灿 王晶 +2 位作者 全燮 陈硕 于洪涛 《大连理工大学学报》 EI CAS CSCD 北大核心 2019年第6期580-586,共7页
非均相催化臭氧氧化技术是一种高效的废水处理技术,但目前非均相臭氧催化剂主要为粉体形态,常用于静态或半连续态反应器中,其于固定床中的催化性能并不明确.设计了连续态固定床反应体系,以γ-Al2O3颗粒为载体,Mn、Fe、Ce的氧化物为活性... 非均相催化臭氧氧化技术是一种高效的废水处理技术,但目前非均相臭氧催化剂主要为粉体形态,常用于静态或半连续态反应器中,其于固定床中的催化性能并不明确.设计了连续态固定床反应体系,以γ-Al2O3颗粒为载体,Mn、Fe、Ce的氧化物为活性组分制备负载型催化剂,并以对硝基苯酚(PNP)为目标污染物,探究其在不同工艺条件下的催化性能.实验结果表明,负载CeO2的催化剂催化效果最好;化学需氧量(COD)和总有机碳(TOC)的去除率随着活性组分CeO2负载量、水力停留时间(HRT)、O3浓度的增加而增加;当CeO2负载量为12.3%、HRT为15 min、O3浓度为16.2mg/L时,6h COD和TOC平均去除率分别达到86.3%和91.7%;此外,该体系在pH为5.0~9.0均表现出良好催化性能,并具有良好的长时间运行能力. 展开更多
关键词 非均相催化臭氧氧化 固定床 金属氧化物 Γ-AL2O3
下载PDF
Bifunctional S-scheme g-C3N4/Bi/BiVO4 hybrid photocatalysts toward artificial carbon cycling 被引量:20
6
作者 quan xie Wanmei He +3 位作者 Shengwei Liu Chuanhao Li Jinfeng Zhang Po Keung Wong 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第1期140-153,共14页
Although both the aerobic photocatalytic oxidation of organic pollutants into CO2 and the anaerobic photocatalytic reduction of CO2 into solar fuels have been intensively studied,few efforts have been devoted to combi... Although both the aerobic photocatalytic oxidation of organic pollutants into CO2 and the anaerobic photocatalytic reduction of CO2 into solar fuels have been intensively studied,few efforts have been devoted to combining these carbon-involved photocatalytic oxidation-reduction processes together,by which an artificial photocatalytic carbon cycling process can be established.The key challenge lies in the exploitation of efficient bifunctional photocatalysts,capable of triggering both aerobic oxidation and anaerobic reduction reactions.In this work,a bifunctional ternary g-C3N4/Bi/BiVO4 hybrid photocatalyst is successfully constructed,which not only demonstrates superior aerobic photocatalytic oxidation performance in degrading an organic pollutant(using the dye,Rhodamine B as a model),but also exhibits impressive photocatalytic CO2 reduction performance under anaerobic conditions.Moreover,a direct conversion of Rhodamine B to solar fuels in a one-pot anaerobic reactor can be achieved with the as-prepared ternary g-C3N4/Bi/BiVO4 hybrid photocatalyst.The excellent bifunctional photocatalytic performance of the g-C3N4/Bi/BiVO4 photocatalyst is associated with the formation of efficient S-scheme hybrid junctions,which contribute to promoting the appropriate charge dynamics,and sustaining favorable charge potentials.The formation of the S-scheme heterojunction is supported by scavenger studies and density functional theory calculations.Moreover,the in-situ formed plasmonic metallic Bi nanoparticles in the S-scheme hybrid g-C3N4/Bi/BiVO4 photocatalyst enhances vectorial interfacial electron transfer.This novel bifunctional S-scheme g-C3N4/Bi/BiVO4 hybrid photocatalyst system provides new insights for the further development of an integrated aerobic-anaerobic reaction system for photocatalytic carbon cycling. 展开更多
关键词 S-scheme Plasmonic Bi nanoparticles Photocatalytic CO2 reduction Photocatalytic degradation of organic pollutants Carbon cycling
下载PDF
Catalytic reductive dechlorination of p-chlorophenol in water using Ni/Fe nanoscale particles 被引量:18
7
作者 ZHANG Wei-hua quan xie ZHANG Zhuo-yong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第3期362-366,共5页
Nanoscale bimetallic Ni/Fe particles were synthesized from the reaction of sodium borohydride (NaBH4) with reduction of Ni^2+ and Fe^2+ in aqueous solution. The obtained Ni/Fe particles were characterized by TEM ... Nanoscale bimetallic Ni/Fe particles were synthesized from the reaction of sodium borohydride (NaBH4) with reduction of Ni^2+ and Fe^2+ in aqueous solution. The obtained Ni/Fe particles were characterized by TEM (transmission electron microscope), XRD (X-ray diffractometer), and N2-BET. The dechlorination activity of the Ni/Fe was investigated using p-chlorophenol (p-CP) as a probe agent. Results demonstrated that the nanoscale Ni/Fe could effectively dechlorinate p-CP at relatively low metal to solution ratio of 0.4 g/L (Ni 5 wt%). The target with initial concentration ofp-CP 0.625 mmol/L was dechlorinted completely in 60 rain under ambient temperature and pressure. Factors affecting dechlorination efficiency, including reaction temperature, pH, Ni loading percentage over Fe, and metal to solution ratio, were investigated. The possible mechanism of dechlorination ofp-CP was proposed and discussed. The pseudo-first- order reaction took place on the surface of the Ni/Fe bimetallic particles, and the activation energy of the dechlorination reaction was determined to be 21.2 kJ/mol at the temperature rang of 287-313 K. 展开更多
关键词 Ni/Fe bimetal nanoscale particles catalytic reduction p-CP DECHLORINATION
下载PDF
Photocatalytic remediation ofγ-hexachlorocyclohexane contaminated soils using TiO_2 and montmorillonite composite photocatalyst 被引量:5
8
作者 ZHAO Xu quan xie +2 位作者 CHEN Shuo ZHAO Hui-min LIU Yu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第3期358-361,共4页
TiO2 and montmorillonite composite photocatalysts were prepared and applied in degrading γ-hexachlorocyclohexane (γ-HCH) in soils. After being spiked with γ-HCH, soil samples loaded with the composite photocataly... TiO2 and montmorillonite composite photocatalysts were prepared and applied in degrading γ-hexachlorocyclohexane (γ-HCH) in soils. After being spiked with γ-HCH, soil samples loaded with the composite photocatalysts were exposed to UV-light irradiation. The results indicated that the photocatalytic activities of the composite photocatalysts varied with the content of TiO2 in the order of 10%〈70%〈50% 〈30%, Moreover, the photocatalytic activity of the composite photocatalysts with TiO2 content 30% was higher than that of the pure P25 with the same mass of TiO2. The strong adsorption capacity of the composite photocatalysts and quantum size effect may contribute to its increased photocatalytic activities. In addition, effect of dosage of composite photocatalysts and soil pH on γ-HCH photodegradation was investigated. Pentachlorocyclohexene, trichlorocyclohexene, and dichlorobenzene were detected as photodegradation intermediates, which were gradually degraded with the photodegradation evolution. 展开更多
关键词 TiO2 MONTMORILLONITE Γ-HCH soil surfaces composite photocatalysts
下载PDF
氮掺杂多孔碳包覆钴金属催化去除有机污染物(英文)
9
作者 王冠龙 毕晨曦 +2 位作者 陈硕 全燮 于洪涛 《大连理工大学学报》 EI CAS CSCD 北大核心 2018年第4期331-341,共11页
活化过硫酸氢盐(PMS)产生具有强氧化能力的硫酸根自由基(SO_4~·-)的高级氧化技术在有机污染物降解方面正受到越来越多的关注.选择ZIF-67为前驱体通过两步热处理构建氮掺杂多孔碳包覆钴金属的核壳催化剂(Co@NPC),并通过改变碳化温... 活化过硫酸氢盐(PMS)产生具有强氧化能力的硫酸根自由基(SO_4~·-)的高级氧化技术在有机污染物降解方面正受到越来越多的关注.选择ZIF-67为前驱体通过两步热处理构建氮掺杂多孔碳包覆钴金属的核壳催化剂(Co@NPC),并通过改变碳化温度调控多孔碳壳的结构与组成,研究多孔碳结构组成对催化性能的影响.实验结果表明,随着碳化温度的升高,介孔孔容与碳壳厚度逐渐增大,催化剂的性能随着介孔孔容与碳壳厚度比值的增加而显著提高.850℃碳化的Co@NPC催化降解苯酚的动力学常数是多相催化剂四氧化三钴的110.8倍,甚至是之前报道过最优的PMS催化剂均相钴离子的4.6倍.此外,当包覆的碳层数大于3时,Co@NPC表现出良好稳定性,钴溶出明显减少.碳壳的介孔孔容与厚度是影响PMS活化的重要因素,Co@NPC的催化性能还受到石墨氮含量的影响. 展开更多
关键词 过硫酸氢盐(PMS) 硫酸根自由基 氮掺杂多孔碳 核壳催化剂 苯酚降解
下载PDF
Solubility and sorption of petroleum hydrocarbons in water and cosolvent systems 被引量:2
10
作者 Chen Hong Chen Shuo +2 位作者 quan xie Zhao Yazhi Zhao Huimin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第10期1177-1182,共6页
The solubility and sorption of oil by uncontaminated clay loam and silt loam soils were studied from water and cosolvent/water solutions using batch techniques. The data obtained from the dissolution and sorption expe... The solubility and sorption of oil by uncontaminated clay loam and silt loam soils were studied from water and cosolvent/water solutions using batch techniques. The data obtained from the dissolution and sorption experiments were used to evaluate the applicability of the cosolvent theory to oil as a complex mixture. Aqueous solubility and soil-water distribution coeffcients (Kd,w, L/kg) were estimated by extrapolating from cosolvent data, with a log-linear cosolvency model, to the volume fraction of cosolve... 展开更多
关键词 COSOLVENT SOLUBILITY SORPTION dissolved organic carbon OIL
下载PDF
Effects of nature organic matters and hydrated metal oxides on the anaerobic degradation of lindane,p,p'-DDT and HCB in sediments 被引量:1
11
作者 ZHAO Xu quan xie +3 位作者 ZHAO Hui min CHEN Jing wen CHEN Shou ZHAO Ya zhi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第5期618-621,共4页
Effects of natural organic matters(NOM) and hydrated metal oxides(HMO) in sediments on the anaerobic degradation of γ 666, p,p' DDT and HCB were investigated by means of removing NOM and HMO in Liaohe R... Effects of natural organic matters(NOM) and hydrated metal oxides(HMO) in sediments on the anaerobic degradation of γ 666, p,p' DDT and HCB were investigated by means of removing NOM and HMO in Liaohe River sediments sequentially. The results showed that the anaerobic degradation of γ 666, p,p' DDT and HCB followed pseudo first order kinetics in different sediments. But, the extents and rates of degradation were different, even the other conditions remained the same. Anaerobic degradation rates of γ 666, p,p' DDT and HCB were 0 020 d -1 , 0 009 d -1 and 0 035 month -1 respectively for the sediments without additional carbon resources. However, with addition of carbon resources, the anaerobic degradation rates of γ 666, p, p ' DDT and HCB were 0 071 d -1 , 0 054 d -1 and 0 088 month -1 in the original sediments respectively. After removing NOM, the rates were decreased to 0 047 d -1 , 0 037 d -1 and 0 066 month -1 ; in the sediments removed NOM and HMO, the rates were increased to 0 067 d -1 , 0 059 d -1 and 0 086 month -1 . These results indicated that NOM in the sediments accelerated the anaerobic degradation of γ 666, p,p' DDT and HCB; the HMO inhibited the anaerobic degradation of γ 666, p,p' DDT and HCB. 展开更多
关键词 LINDANE p p' DDT HCB anaerobic degradation SEDIMENTS natural organic matters
下载PDF
Description of adsorption of hydrophobic organic compounds on sediment using multi-component adsorption model 被引量:1
12
作者 quan xie LIU Zhen yu +2 位作者 XUE Da ming ZHAO Ya zhi YANG Feng lin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第2期195-203,共9页
A chemical sequential separation procedure for sediment has been developed for the adsorptive investigation of hydrophobic organic compounds(HOCs) including four fractions: carbonate, hydrous metallic oxide(ferric oxi... A chemical sequential separation procedure for sediment has been developed for the adsorptive investigation of hydrophobic organic compounds(HOCs) including four fractions: carbonate, hydrous metallic oxide(ferric oxide, manganese oxide and alumina), clay and organic matter. Adsorption isotherms of these hydrophobic solute probes, such as hexachloroethane, lindane and 1,2,4,5 tetrachlorobenzene were measured for model sorbents, model and natural sediment, and the latter of which was pretreated with the simplified sequential separation method. The linear and Langmuir models are applied to correlate the experimental data of humic substance and other model sorbents respectively. Multi component Adsorptive Model (MCAM) was used to simulate adsorption isotherms of model and natural sediment. The results reveal that(1) the separation efficiencies of carbonate, organic matter, ferric oxide, manganese oxide and alumina are 98.1%, 72.5%, 82.6%, 93.5% and 83.3%, respectively; (2) except for removing metallic oxide, the external structure of sediment is not changed greatly after separation; (3) the MCAM correlates the data of adsorption isotherm rather well with the maximal relative deviations of 9.76%, 6.78% and 9.53% for hexachloroethane, lindane and 1,2,4,5 tetrachlorobenaze in model sediment, respectively. The MCAM can clearly give expression to the different adsorptive mechanisms for HOCs in organic and inorganic matter, though the experimental data in each component are not very accurate due to the sequential separation efficiency. 展开更多
关键词 hydrophobic organic compounds SEDIMENT ADSORPTION MODEL
下载PDF
Modulation of Schottky barrier in XSi_(2)N_(4)/graphene(X=Mo and W)heterojunctions by biaxial strain 被引量:1
13
作者 Qian Liang Xiang-Yan Luo +2 位作者 Yi-Xin Wang Yong-Chao Liang quan xie 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第8期578-586,共9页
Reducing the Schottky barrier height(SBH)and even achieving the transition from Schottky contacts to Ohmic contacts are key challenges of achieving high energy efficiency and high-performance power devices.In this pap... Reducing the Schottky barrier height(SBH)and even achieving the transition from Schottky contacts to Ohmic contacts are key challenges of achieving high energy efficiency and high-performance power devices.In this paper,the modulation effects of biaxial strain on the electronic properties and Schottky barrier of Mo Si_(2)N_(4)(MSN)/graphene and WSi_(2)N_(4)(WSN)/graphene heterojunctions are examined by using first principles calculations.After the construction of heterojunctions,the electronic structures of MSN,WSN,and graphene are well preserved.Herein,we show that by applying suitable external strain to a heterojunction stacked by MSN or WSN—an emerging two-dimensional(2D)semiconductor family with excellent mechanical properties—and graphene,the heterojunction can be transformed from Schottky ptype contacts into n-type contacts,even highly efficient Ohmic contacts,making it of critical importance to unleash the tremendous potentials of graphene-based van der Waals(vd W)heterojunctions.Not only are these findings invaluable for designing high-performance graphene-based electronic devices,but also they provide an effective route to realizing dynamic switching either between n-type and p-type Schottky contacts,or between Schottky contacts and Ohmic contacts. 展开更多
关键词 MoSi_(2)N_(4) Schottky barrier height HETEROJUNCTION biaxial strain
下载PDF
Aggregation Behavior of Amphiphilic PAMAM-Based Hyperbranched Polymer in the Presence of Conventional Small Molecular Surfactants 被引量:2
14
作者 Hui Yang Danfeng Yu +3 位作者 Hui Wang quan xie Jiazhong Wu Jinben Wang 《Advances in Chemical Engineering and Science》 2013年第3期11-18,共8页
Hyperbranched polymer composed of G1 polyamidoamine (PAMAM) and branched with poly (propylene oxide) (PPO)-block-poly (ethylene oxide) (PEO) was investigated to interact with sodium dodecyl sulfate (SDS) and di-dodecy... Hyperbranched polymer composed of G1 polyamidoamine (PAMAM) and branched with poly (propylene oxide) (PPO)-block-poly (ethylene oxide) (PEO) was investigated to interact with sodium dodecyl sulfate (SDS) and di-dodecyl dimethyl ammonium bromide (DDAB), respectively, by the methods of turbidity titration and analysis, rheology measurements, dynamic light scattering (DLS) and transmission electron microscopy (TEM). It was noticeable that even at extremely low concentration of SDS (even far from the critical micelle concentration (cmc)), the system exhibits high turbidity, indicating that SDS molecules can insert into cationic amine groups and hydrophobic microenvironment, resulting in the formation of polymer-SDS complexes with large size. At the SDS concentration range of below 0.1 mM, the turbidity and cloud point (CP) temperature of the system keep almost invariable, mostly because of the repulsion between SDS molecules and the complexes. And, therefore, the size of the mixed aggregates retains almost constant. In the case of vesicle system of DDAB, the aggregates are in the size of 100 nm - 200 nm and 500 nm - 3000 nm at the concentrations of 30 mM and 100 mM, respectively. However, in the mixture of hyperbranched polymer with DDAB, by comparison, the size is smaller in a binary system than that of in DDAB system. So it is reasonable to infer that DDAB molecules remove from multilamellar vesicles of DDAB to the hydrophobic microenvironment of hyperbranched polymer aggregates, with the addition of the hyperbranched polymer. It leads to the destruction of the gel-like conformation in DDAB system, leading to the shear thinning of the mixture and, as a result, the viscoelastic character of the system is lost in a large degree. 展开更多
关键词 HYPERBRANCHED Polymer AGGREGATE CONFORMATION Complex
下载PDF
First-principles study on optic-electronic properties of doped formamidinium lead iodide perovskite
15
作者 Xin-Feng Diao Yan-Lin Tang quan xie 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第1期620-627,共8页
We have discussed the materials of solar cell based on hybrid organic–inorganic halide perovskites with formamidinium(NH_2CH = NH_2^+or FA) lead iodide. Firstly, we build the structure of formamidinium lead iodide(FA... We have discussed the materials of solar cell based on hybrid organic–inorganic halide perovskites with formamidinium(NH_2CH = NH_2^+or FA) lead iodide. Firstly, we build the structure of formamidinium lead iodide(FAPbI_3) by using the material studio. By using the first-principles calculations, the energy band structure, density of states(DOS), and partial DOS(PDOS) of the hydrazine-iodide lead halide are obtained. Then, we theoretically analyze a design scheme for perovskite solar cell materials, published in [Science 354, 861(2016)], with the photoelectric conversion efficiency that can reach 20.3%. Also, we use non-toxic elements to replace lead in FAPbI_3 without affecting its photoelectric conversion efficiency. Here in this work, we explore the energy band structure, lattice constant, light absorption efficiency, etc. After the Ca, Zn, Ge Sr, Sn, and Ta atoms replacing lead(Pb) and through comparing the spectral distributions of the solar spectrum, it can be found that FAGeI_3, FASnI_3, and FAZnI_3 have better absorbance characteristics in the solar spectrum range. If the band gap structure is taken into account, FAGeI_3 will become an ideal material to replace FAPbI_3, although its performance is slightly lower than that of FAPbI_3. The toxicity of Pb is taken into account, and the Ge element can be used as a substitute element for Pb. Furthermore, we explore one of the perovskite materials, i.e., FA0.75Cs_(0.25)Sn_(0.25)Ge_(0.75)I_3 whose photovoltaic properties are close to those of FA_(0.75)Cs_(0.25)Sn_(0.5)Pb_(0.5)I_3, but the former does not contain toxic atoms.Our results pave the way for further investigating the applications of these materials in relevant technologies. 展开更多
关键词 PEROVSKITE BAND structure optic-electronic properties SOLAR cell
下载PDF
Relation of asid- volatile sulfide and clay content of sediment to the bioavailability of zinc and cadmium:laboratory plus field experiment
16
作者 HAN Jianbo WANG Juying +1 位作者 MA Deyi quan xie 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第5期61-67,共7页
Organic matter and iron and maganese oxides have been considered as the major affecting factors for metals in anoxic or oxidized sediment. In recent research, clay and sulfide are found as major factors in oxic or oxi... Organic matter and iron and maganese oxides have been considered as the major affecting factors for metals in anoxic or oxidized sediment. In recent research, clay and sulfide are found as major factors in oxic or oxidized sediments that might affect bioavailability of metals. To test this hypothesis, the influence of sulfide, measured as acid-volatile sulfide (AVS), and clay content on the bioavailability of zinc and cadmium in sediments was examined. Laboratory simulative experiment and field verification experiment were conducted, showing that the bioavailability of zinc and cadmium is strongly correlated to AVS and clay content in sediments. Taking into account both AVS and clay parameters in sediments together can better indicate the bioavailability of zinc and cadmium rather than considering one of them alone. 展开更多
关键词 AVS CLAY BIOAVAILABILITY ZINC cadmium
下载PDF
催化湿式过氧化氢氧化耦合Fe2O3/Al2O3膜分离处理有机废水(英文)
17
作者 刘祎玮 全燮 +2 位作者 陈硕 于洪涛 杜磊 《大连理工大学学报》 EI CAS CSCD 北大核心 2019年第6期587-596,共10页
为提高有机废水的降解效率,设计了一种耦合陶瓷管式膜分离和催化湿式过氧化氢氧化(CWPO)技术的反应器.通过溶胶凝胶法将Fe2O3/Al2O3催化剂涂覆到陶瓷管式膜基底上.并通过控制PVA的浓度和涂覆次数,将制备的膜孔径优化到超滤范围.在进行的... 为提高有机废水的降解效率,设计了一种耦合陶瓷管式膜分离和催化湿式过氧化氢氧化(CWPO)技术的反应器.通过溶胶凝胶法将Fe2O3/Al2O3催化剂涂覆到陶瓷管式膜基底上.并通过控制PVA的浓度和涂覆次数,将制备的膜孔径优化到超滤范围.在进行的CWPO实验中,优化了pH、温度、压力和H2O2浓度操作条件.实验表明,在20 mmol/L H2O2,pH=6,90℃和0.4 MPa的反应条件下,苯酚在150 min内能完全降解,TOC去除率为70%.5次连续重复实验和溶出测试表明Fe2O3/Al2O3陶瓷膜具有良好的稳定性和可重复性.该反应器耦合CWPO与膜分离技术为有机废水处理领域提供了新的思路. 展开更多
关键词 催化湿式过氧化氢氧化 Fe2O3/Al2O3膜催化剂 苯酚 高级氧化技术
下载PDF
Evolution of defects and deformation mechanisms in different tensile directions of solidified lamellar Ti-Al alloy
18
作者 Yutao Liu Tinghong Gao +7 位作者 Yue Gao Lianxin Li Min Tan quan xie Qian Chen Zean Tian Yongchao Liang Bei Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第4期518-524,共7页
Two-phaseγ-TiAl/α_(2)-Ti_(3)Al lamellar intermetallics have attracted considerable attention because of their excellent strength and plasticity.However,the exact deformation mechanisms remain to be investigated.In t... Two-phaseγ-TiAl/α_(2)-Ti_(3)Al lamellar intermetallics have attracted considerable attention because of their excellent strength and plasticity.However,the exact deformation mechanisms remain to be investigated.In this paper,a solidified lamellar Ti-Al alloy with lamellar orientation at 0°,17°,and 73°with respect to the loading direction was stretched by utilizing molecular dynamics(MD)simulations.The results show that the mechanical properties of the sample are considerably influenced by solidified defects and tensile directions.The structure deformation and fracture were primarily attributed to an intrinsic stacking fault(ISF)accompanied by the nucleated Shockley dislocation,and the adjacent extrinsic stacking fault(ESF)and ISF formed by solidification tend to form large HCP structures during the tensile process loading at 73°.Moreover,cleavage cracking easily occurs on theγ/α_(2)interface under tensile deformation.The fracture loading mechanism at 17°is grain boundary slide whereas,at 73°and 0°,the dislocation piles up to form a dislocation junction. 展开更多
关键词 molecular dynamics simulation solidified lamellar Ti-Al alloy tensile directions γ/α_(2)interface
下载PDF
An approximate analytical solution for transient gas flows in a vertically fractured well of finite fracture conductivity
19
作者 Yun-Hu Lu Kang-Ping Chen +2 位作者 Yan Jin Hong-Da Li quan xie 《Petroleum Science》 SCIE CAS CSCD 2022年第6期3059-3067,共9页
An analytical solution in physical variable space is presented for transient gas flows during constant-rate production from a vertically-fractured well in an infinite homogeneous reservoir with finite fracture conduct... An analytical solution in physical variable space is presented for transient gas flows during constant-rate production from a vertically-fractured well in an infinite homogeneous reservoir with finite fracture conductivity.The solution is based on the short-time asymptotic solution and a new approximate transient elliptical flow solution,which covers transient flows from the bilinear flow regime to the pseudo-radial flow regime.The solution covers the well-known asymptotic solutions in both short-and long-time limits of bilinear and pseudo-radial flows.The analytical model provides a practical and reliable engineering tool to evaluate the fractured reservoir properties,which can be programmed using a spreadsheet. 展开更多
关键词 Transient gas pressure Fractured well Analytical solution
下载PDF
Comparative study of 99Tc-MDP and zoledronic acid in the treatment of osteoporosis
20
作者 Ying Zhou Wei-Min Pan +6 位作者 Wen Sun Chao-Qun Wang Juan-Juan Yan quan xie YingHuang Huan Xiao Wei-Wen Yan 《Journal of Hainan Medical University》 2020年第16期35-39,共5页
Objective:To compare the efficacy and mechanism of zoledronic acid and Tc-MDP in the treatment of osteoporosis.Methods:From July 2011 to November 2015,232 patients with primary osteoporosis were selected and treated i... Objective:To compare the efficacy and mechanism of zoledronic acid and Tc-MDP in the treatment of osteoporosis.Methods:From July 2011 to November 2015,232 patients with primary osteoporosis were selected and treated in The First Affiliated Hospital of Hainan Medical College were selected and were divided into the 116 patients in the Tc-MDP group and 116 patients in the zoledronic acid group accorded to the treatment ways.The zoledronic acid group were given zoledronic acid treatment,1 time in one year.The Tc-MDP group were given Tc-MDP treatment,and the treatment were treated for 10 days for 1 course,1 course for 3 months,and a total of 3 years of treatment were observed.The prognosis and the changes of bone mineral density and hematological parameters were recorded.Results:The total effective rates of the zoledronic acid group and Tc-MDP group were 99.1%and 90.0%,respectively,and the zoledronic acid group were significantly higher than the Tc-MDP group(P<0.05).The bone mineral density of lumbar vertebrae and hip after treatment were significantly higher than that of the two groups before treatment,and the zoledronic acid group were also significantly higher than the Tc-MDP group(P<0.05).The joint tenderness scores of the two groups were significantly lower than those before treatment,and the Tc-MDP group were also significantly lower than the zoledronic acid group(P<0.05).There were no significant differences in serum calcium and blood phosphorus levels compared between the two groups(P>0.05),and the erythroeyte sedimentation rate(ESR)levels were lower than before treatment(P<0.05),The ESR levels of the Tc-MDP group were also significantly lower than that of the zoledronic acid group(P<0.05).Conclusion:The zoledronic acid and the application of Tc-MDP in the treatment of osteoporosis can increase bone density,relieve joint tenderness symptoms,reduce ESR content,and will not affect patients'blood calcium and blood phosphorus levels.However,zoledronic acid increases bone density significantly are better than the Yunke,and Yunke relieves joint pain significantly are more than zoledronic acid. 展开更多
关键词 Zoledronic acid TC-MDP OSTEOPOROSIS Erythrocyte sedimentation rate Bone density
下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部