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Some New Water-Soluble Phosphines with the Involvement of the Trivalent Rare Earth Ion
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作者 Chen Xinlan,Lei Peng, Zhang Let, Pei Hong, Zhang Lun(Department of Chemistry, Wuhan University, Wuhan 430072,China)(State Key Laboratery for Oxo Synthesis and Selective Oxidation,Lanzhou Institute of Chemical Physics, Chinese Academy of Science, Lanzhou 7 《Wuhan University Journal of Natural Sciences》 EI CAS 1998年第1期86-91,共6页
The new type of water-soluble phosphine with the involvement of the trivalent rare earth ion, TPPTS?Ln (Ln=Eu, Dy, Er, Tm, Yb, Lu; and TPPTS=tris (m-sulfonatophenyl) phosphine), were synthesized from the precursor TPP... The new type of water-soluble phosphine with the involvement of the trivalent rare earth ion, TPPTS?Ln (Ln=Eu, Dy, Er, Tm, Yb, Lu; and TPPTS=tris (m-sulfonatophenyl) phosphine), were synthesized from the precursor TPPTS?Na3 and oxides of rare earth. The chemical composition of TPPTS?Ln was determined by elemental analysis and ICP-AES. IR, Raman showed that the sulfonate group in the complexes was a tridentate ligand.31P NMR, TG-DTA, molar conductivity and the fluorescence of these complexes were also recorded and discussed. 展开更多
关键词 rare earth complex water soluble phosphine synthesis and properties
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AQUEOUS PHASE RHODIUM HYDROFORMYLATION OF DODECENE-1 WITH SURFACE ACTIVE WATER-SOLUBLE PHOSPHINE
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作者 Yuan Yong YAN Huan Pei ZUO Zi Lin JIN(College of Chemical Engineering, Dalian University of Technology, Dalian 116012) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第4期377-380,共4页
The surface active water-soluble phosphine, P[p-C6H4O(CH2CH2O)nH]3, n=4, is used to generate an squeous rhoditun catalyst for the hydroformylation of dodecene-1. Under I00℃, 5.0 MPa (CO/H2=1∶1 ), pH=6.5, and reachon... The surface active water-soluble phosphine, P[p-C6H4O(CH2CH2O)nH]3, n=4, is used to generate an squeous rhoditun catalyst for the hydroformylation of dodecene-1. Under I00℃, 5.0 MPa (CO/H2=1∶1 ), pH=6.5, and reachon time 4h, the conversion of dodecene-1 was 96.0%, the yield for aldehyde was 84.0%. and n/i =1.8. The catalyst can be reused for more than four times without any appreciable loss in activity and selechvity. 展开更多
关键词 SURFACE AQUEOUS DODECENE OF PHASE phosphinE RHODIUM soluble ACTIVE water
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Synthesis of a New Type of Amphilic and Water - soluble Tertiary Phosphine Ligands Substituted by an Ethoxylated Phosphonic Acid Chain and Their Palladium Complexes
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作者 Xiang Kai FU Xue Bing MA 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第9期839-842,共4页
The highly water-soluble phosphine ligands Na2O3PCH2CH2NH(CH2CH2O)nCH2CH2N- (CH2PPh2)2 (n=1,2,3) were prepared by a new and simple route under mild conditions in good yield; the palladium (II) complexes of the ligands... The highly water-soluble phosphine ligands Na2O3PCH2CH2NH(CH2CH2O)nCH2CH2N- (CH2PPh2)2 (n=1,2,3) were prepared by a new and simple route under mild conditions in good yield; the palladium (II) complexes of the ligands 3a~c with 2:1 or 4:1 -PPh2 to Pd2+ molar ratio were also prepared and characterized . 展开更多
关键词 water-soluble diphenylphosphinomethyl phosphine ligands palladium complexes synthesis.
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Solvent de binding of water soluble binder in powder injection moulding 被引量:14
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作者 Li Songlin(李松林) Huang Baiyun(黄伯云) +1 位作者 Qu Xuanhui(曲选辉) Li Yimin(李益民) 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第3期578-581,共4页
The solvent debinding of water soluble binder in powder injection moulding (MIM) was investigated systematically, including the effects of solvent types, temperature and the thickness of green parts on the solvent deb... The solvent debinding of water soluble binder in powder injection moulding (MIM) was investigated systematically, including the effects of solvent types, temperature and the thickness of green parts on the solvent debinding rate. After studying the debinding of a green part with a thickness of 4.26 mm, it was found that, the debinding rate of polyethylene glycol(PEG) in water and alcohol was high initially, and then decreased; however, it would increase with temperature increasing. At room temperature, the dissolution rate of PEG in water was higher than that in alcohol, but the latter would be much faster with temperature increasing because the debinding activation energy in alcohol was 51.44 kJ·mol -1 ·K -1 , much higher than 24.23 kJ·mol -1 ·K -1 in water. With a green part thickness larger than 4.26 mm, the debinding was controlled by diffusion; but with that smaller than 2.36 mm, the debinding was controlled by both dissolution and diffusion. 展开更多
关键词 powder injection MOULDING water soluble binders SOLVENT DEBINDING
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Biodegradability of soil water soluble organic carbon extracted from seven different soils 被引量:7
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作者 SCAGLIA Barbara ADANI Fabrizio 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第5期641-646,共6页
Water soluble organic carbon (WSOC) is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WS... Water soluble organic carbon (WSOC) is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WSOC extracted from 7 soils differently managed. WSOC was extracted from soil with water (soil/water ratio of 1:2, W/V) for 30 min, and then tested for biodegradability by a liquid state respirometric test. Result obtained confirmed the finding that WSOC biodegradability depended on the both land use and management practice. These results suggested the biodegradability test as suitable method to characterize WSOC, and provided useful information to soil fertility. 展开更多
关键词 biodegradability test cumulated oxygen uptake water extractable organic carbon water soluble organic carbon
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Relationship Between Soluble Protein,Chlorophyll and ATP in Drought-Resistant Sweet Potato Under Water Stress 被引量:8
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作者 ZHANG Ming-sheng, XIE Bo, TAN Feng and ZHANG Qi-tang(Agricultural College , Guizhou University , Guiyang 550025 , P. R. China The College of Life Science , Southwest China Normal University, Chongqing 400715 , P.R.China) 《Agricultural Sciences in China》 CAS CSCD 2002年第12期1329-1333,共5页
Some indices concerning the metabolism of substance and energy in sweet potato leaves under water stress were studied. The results showed an obvious increase in soluble protein content. Compared with control, Chl a, C... Some indices concerning the metabolism of substance and energy in sweet potato leaves under water stress were studied. The results showed an obvious increase in soluble protein content. Compared with control, Chl a, Chl b, total Chl contents and the ratio of Chl a to Chl b all decreased to some extent. ATP content increased in some varieties and decreased in others, but the stronger the drought resistance of the variety , the higher the ATP content. The correlation coefficient(r)of the soluble protein content, ratio of Chl a to Chl b and ATP content as a percentage of the drought-resistant sweet potato control variety are 0. 8968, - 0. 8509 and 0. 8200, respectively, P<0. 01. So these indices can be used to evaluate the drought resistance of different sweet potato varieties. 展开更多
关键词 Sweet potato water stress soluble protein CHLOROPHYLL ATP Drought resistance
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Photocatalytic Degradation of Water-Soluble Dyes by LaCoO_3 被引量:9
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作者 傅希贤 杨秋华 +2 位作者 王俊珍 白树林 桑丽霞 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第4期424-426,共3页
Perovskite type oxides LaCoO 3 was prepared by citrate method in granula of 20~30 nm. Using a fluorescent Hg lamp or sunlight as irradiator, the degradation experiments of various water soluble dyes were carried o... Perovskite type oxides LaCoO 3 was prepared by citrate method in granula of 20~30 nm. Using a fluorescent Hg lamp or sunlight as irradiator, the degradation experiments of various water soluble dyes were carried out in the suspension system of LaCoO 3. The results show that the perovskite type oxide LaCoO 3 has good photocatalytic activity. With the study of X ray photoelectron spectroscopy and photoacoustic spectra, its photocatalytic activity is mainly related with the factors such as the d electron structure of ion Co 3+ , Co O binding energy and adsorbed oxygen on the surface etc. 展开更多
关键词 catalytic chemistry water soluble dye perovskite type LaCoO 3 photocatalytic degradation rare earths
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Study on the Rapid Method to Predict Longevity of Controlled Release Fertilizer Coated by Water Soluble Resin 被引量:10
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作者 DAI Jian-jun FAN Xiao-lin +2 位作者 YU Jian-gang LIU Fang ZHANG Qiao 《Agricultural Sciences in China》 CAS CSCD 2008年第9期1127-1132,共6页
The study discussed the rapid method to test and predict the longevity of controlled release fertilizers (CRFs) coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dis... The study discussed the rapid method to test and predict the longevity of controlled release fertilizers (CRFs) coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dissolving incubation and higher temperature leaching were used to study the patterns of the nutrient release of the CRFs. The correlation analysis between the days at 25℃ and the hours at 80℃ of Trincote 1 and Trincote 2 for the same cumulative release rates were conducted. Patterns of cumulative nutrient release curve followed one factor quadratic regression equation at each given temperatures, and each of relative coefficient was bigger than 0.995. As the temperature increased, nutrients release of the CRFs increased. The longevity of resin coated CRFs were predicted by use of both the cumulative nutrients release equation at 80℃ and the regression equation of release time needed for the same cumulative release rates between 25 and 80℃. There were only 0.3-6.9% relative errors between the tested longevity and predicted one. In conclusion, the longevity of resin coated CRFs could be predicted more quickly and precisely by use of the higher temperature short-term leaching method than that of the traditional differential release rate. The longevity of resin coated CRF could be rapidly and precisely predicted in a few hours by application of the higher temperature shortterm leaching method. 展开更多
关键词 controlled release fertilizer (CRF) water soluble resin coating longevity of CRF rapid test method
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Modeling the formation of soluble microbial products(SMP) in drinking water biofiltration 被引量:3
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作者 Yu Xin Ye Lin Wei Gu 《Water Science and Engineering》 EI CAS 2008年第3期93-101,共9页
Both a theoretical and an empirical model were developed for predicting the formation of soluble microbial products (SMP) during drinking water biofiltration. Four pilot-scale biofilters with ceramsite as the medium... Both a theoretical and an empirical model were developed for predicting the formation of soluble microbial products (SMP) during drinking water biofiltration. Four pilot-scale biofilters with ceramsite as the medium were fed with different acetate loadings for the determination of SMP formation. Using numerically simulated and measured parameters, the theoretical model was developed according to the substrate and biomass balance. The results of this model matched the measured data better for higher SMP formation but did not fit well when SMP formation was lower. In order to better simulate the reality and overcome the difficulties of measuring the kinetic parameters, a simpler empirical model was also developed. In this model, SMP formation was expressed as a function of fed organic loadings and the depth of the medium, and a much better fit was obtained. 展开更多
关键词 drinking water BIOFILTRATION soluble microbial products (SMP) mathematical modeling
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Study on Synthesis and Biological Activities of Novel Water-Soluble Metalloporphyrins 被引量:2
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作者 Li Zao-ying, Zhang Yue ning, Xiao Wei, Zhu Xun jin,Gao Zhen ting, Liu Yi College of Chemistry and Molecular Science, Wuhan University, Wuhan, 430072, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2001年第4期841-845,共5页
The synthesis and characterization of a series of metal porphyrins, MII(Por), {Por=dianionic of 5, 10, 15, 20-tetrakis [4-(4′-bromobutyloxy) phenyl]porphyrinato and 5, 10, 15, 20-tetrakis [4-(4′-butyloxypyridine bro... The synthesis and characterization of a series of metal porphyrins, MII(Por), {Por=dianionic of 5, 10, 15, 20-tetrakis [4-(4′-bromobutyloxy) phenyl]porphyrinato and 5, 10, 15, 20-tetrakis [4-(4′-butyloxypyridine bromide)phenyl]porphyrinato, M=Zn, Cu, Mn, Co, Ni, Ru-CO} were described. The complexes 3a-3e were prepared from the reactions of compound 2 with metal acetates in chloroform, and the treatment of 3a-3f with excess of pyridine gave corresponding complexes 4a-4f. These new compounds were identified by absorption spectroscopies,1H-NMR and elemental analyses. The results of biological activity testing for 4a-4f revealed that 4a and 4c had stronger inhibiting action on the growth metabolism ofEsche richia coli. 展开更多
关键词 water soluble metalloporphyrin SYNTHESIS structure characterization biological activity testing
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PREPARATION AND PHOTOSENSITIVITY OF WATER SOLUBLE PHENOLIC RESINS CONTAINING ACRYLOYL AND QUATERNARY AMMONIUM CHLORIDE GROUPS 被引量:2
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作者 谭晓明 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2002年第2期129-136,共8页
New water soluble and photocrosslinkable prepolymers containing acrylate and quaternary ammonium salt groups were synthesized from epoxy phenolic resin via ring-opening reaction with acrylic acid and with aqueous solu... New water soluble and photocrosslinkable prepolymers containing acrylate and quaternary ammonium salt groups were synthesized from epoxy phenolic resin via ring-opening reaction with acrylic acid and with aqueous solution of triethylamine hydrochloride successively. The second reaction needs no phase transfer catalyst to accelerate, since the product formed can act as a phase transfer catalyst. The prepolymer obtained contains both photocrosslinkable acrylate groups and hydrophilic quaternary ammonium salt groups. Optimum conditions for these reactions were studied. The photosensitivity of the prepolymer was also investigated. The effects of different photoinitiators, different crosslinkable diluent monomers and amine accelerator on the photosensitivity of the prepolymer were compared. The photoinitiator of hydrogen abstraction type is still effective without using amine or alcohol as accelerator, because the prepolymer contains a H beside the OH groups formed in the ring-opening reactions. 展开更多
关键词 photosensitive polymer PHOTOCROSSLINKING water soluble polymer epoxy phenolic resin quaternary ammonium salt
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Partitioning of water soluble organic carbon in three sediment size fractions:Effect of the humic substances 被引量:1
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作者 SUN Liying 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第1期113-119,共7页
Water soluble organic carbon (WSOC) in sediments plays an important role in transference and transformation of aquatic pollutants. This article investigated the inherent mechanisms of how sediemnt grain size affect ... Water soluble organic carbon (WSOC) in sediments plays an important role in transference and transformation of aquatic pollutants. This article investigated the inherent mechanisms of how sediemnt grain size affect the partitioning coeffcient (k) of WSOC. Influences of NaOH extracted humic substances were particularly focused on. Sediments were sampled from two cross-sections of the middle Yellow River and sieved into three size fractions (〈 63 μm, 63-100 μm, and 100-300 μm). The total concentration of WSOC in sediments (Cwsoc) and k were estimated using multiple water-sediment ratio experiments. Results showed that Cwsoc ranged from 0.012 to 0.022 mg/g, while k ranged from 0.8 to 3.9 L/kg. Correlations between the spectrum characteristics of NaOH extracted humic substances and k were analyzed. Strong positive correlations are determined between k and the aromaticity indicators of NaOH extracted humic substances in different sediment size fractions. Comparing with finer fractions (〈 63 μm), k is higher in larger size fractions (63- 100 μm and 100-300 μm) related to higher aromaticity degree of NaOH extracted humic substances mostly. While negative relationship between k and the area ratio of fourier transform infrared spectroscopy (FT-IR) at 3400 and 1430 cm^-1 implied that the lowest k was related to the highest concentration of acidic humic groups in particles 〈 63 μm. WSOC in finer fractions (〈 63 μm) is likely to enter into pore water, which may further accelerate the transportation of aquatic contaminants from sediment to water. 展开更多
关键词 humic substances water soluble organic carbon partitioning SEDIMENT
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Water-soluble lipopolymer delivery of N-methyl-D-aspartic acid receptor 2B siRNA relieves chronic neuropathic pain in rats 被引量:1
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作者 Jianhua Lu Yuanxiang Tao +4 位作者 Xue Yang Weifeng Tu Hao Chen Jiaxiang Xiong Chungui Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第29期2279-2283,共5页
Spinal dorsal horn N-Methyl-D-aspartic acid receptor 2B (NR2B) overexpression plays an important role in the production and maintenance of neuropathic pain. Because small interfering RNA (siRNA) can inhibit NR2B e... Spinal dorsal horn N-Methyl-D-aspartic acid receptor 2B (NR2B) overexpression plays an important role in the production and maintenance of neuropathic pain. Because small interfering RNA (siRNA) can inhibit NR2B expression, siRNA may provide a novel approach to treat neuropathic pain and possibly nerve injury. However, an efficient and safe vector for NR2B siRNA has not been discovered. This study shows that a water soluble lipopolymer (WSLP) comprised of low molecular weight polyethyleneimine (PEI) and cholesterol can deliver siRNA targeting NR2B for the treatment of neuropathic pain. Results show that intrathecal injection of WSLP/siRNA complexes for 3 days inhibit NR2B gene expression with reductions in mRNA and protein levels by 59% and 54%, respectively, compared with control rats (P 〈 0.01). Injection of WSLP complexed with scrambled siRNA, or PEI with siRNA did not show this inhibitory effect. Moreover, injection of WSLP/siRNA complexes significantly relieved neuropathic pain at 3, 7, 12, and 21 days, while injection of WSLP with scrambled siRNA or PEI with siRNA did not. These results demonstrate that WSLP can efficiently deliver siRNA targeting NR2B in vivo and relieve neuropathic pain. 展开更多
关键词 water soluble lipopolymer N-Methyl-D-aspartic acid receptor 2B small interfering RNA peripheral nerve injury neuropathic pain
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Effects of Different Water-soluble Fertilizers on Yield and Quality of Strawberry under Integrated Application of Water and Fertilizer 被引量:1
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作者 Rong KANG Jianbiao NIU +1 位作者 Zhengren CHEN Jizu ZHANG 《Asian Agricultural Research》 2018年第12期59-61,66,共4页
Taking Hongyan strawberry as the material and PE drip irrigation tape and fertilizer applicator as the tool of integrated application of water and fertilizer,this experiment studied the effects of six fertilizers incl... Taking Hongyan strawberry as the material and PE drip irrigation tape and fertilizer applicator as the tool of integrated application of water and fertilizer,this experiment studied the effects of six fertilizers including Batian,Jiashili,Wangdefeng,Stanley,volfertile and calcium protein on yield and quality of strawberry. The experimental results showed that different water-soluble fertilizers had different effects on the main economic traits of strawberry. For the maximum single fruit mass,the highest was volfertile treatment( 28. 72 g),followed by calcium protein treatment,and the lowest was Stanley treatment( 23. 89 g). The fruit treated with Batian,volfertile and calcium protein was hard in the texture,the fruit treated with Wangdefeng was harder,that of Stanley was softer,and that of Jiashili was soft. The strawberry fruit treated with Wangdefeng and calcium protein was sweet,the fruit treated with volfertile and Batian was sweet,that treated with Jiashili was sour and sweet,and that treated with Stanley was slightly sour. The fruit treated with calcium protein,volfertile and Batian showed strong storage resistance.Strawberry plants treated with Batian,Wangdefeng,Stanley,and calcium protein showed stronger growth,and strawberry plants showed a semi-opening pattern. The yield of strawberry treated with volfertile was highest( 17 400 kg/ha),which was significantly increased compared with other treatments,followed by that treated by Stanley( 13 140 kg/ha). 展开更多
关键词 water soluble FERTILIZER INTEGRATED APPLICATION of water and FERTILIZER Strawberry Yield Economic traits
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A PRELIMINARY STUDY OF THE WATER—SOLUBLE OLIGOPEPTIDES AND AMINO ACIDS OF GINSENG 被引量:2
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作者 Liu YANG Yun Hua YE Qi Yi XING Department of Chemistry,Peking University Beijing,100871 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第1期51-54,共4页
γ-Amino butyric acid(GABA)and several γ-glutamyl oligopeptides were isolated and identified from water-extract of ginseng.
关键词 A PRELIMINARY STUDY OF THE water soluble OLIGOPEPTIDES AND AMINO ACIDS OF GINSENG TFA
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Application of ion chromatography to the determination of water-soluble inorganic and organic ions in atmospheric aerosols 被引量:5
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作者 YUXue-chun HEKe-bin +4 位作者 MAYong-liang YANGFu-mo DUANFeng-kui ZHENGAi-hua ZHAOCheng-yi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第5期813-815,共3页
A simple, sensitive and convenient ion chromatography(IC) method was established for the simultaneous determination of twelve water-soluble inorganic anions(F -, Cl -, NO - 2, NO - 3, SO 2- 3, SO 2- ... A simple, sensitive and convenient ion chromatography(IC) method was established for the simultaneous determination of twelve water-soluble inorganic anions(F -, Cl -, NO - 2, NO - 3, SO 2- 3, SO 2- 4, PO 3- 4), and fifteen water-soluble organic ions(formate, acetate, MSA, oxalate, malonate, succinate, phthalates, etc.) in atmospheric aerosols. The linear concentrations ranged from 0.005 μg/m 3 to 500 μg/m 3(r = 0.999—0.9999). The relative standard deviation(RSD) were 0.43%—2.00% and the detection limits were from 2.7 ng/m 3 to 88 ng/m 3. The proposed method was successfully applied to the simultaneous determination of those inorganic ions and organic ions in PM 2.5 of Beijing. 展开更多
关键词 ion chromatography water-soluble ions AEROSOLS BEIJING
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Improvement of humidity resistance of water soluble core by precipitation method 被引量:5
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作者 Zhang Long Li Yuancai Zhao Wei 《China Foundry》 SCIE CAS 2011年第2期212-217,共6页
Water soluble core has been widely used in manufacturing complex metal components with hollow configurations or internal channels;however,the soluble core can absorb water easily from the air at room temperature.To im... Water soluble core has been widely used in manufacturing complex metal components with hollow configurations or internal channels;however,the soluble core can absorb water easily from the air at room temperature.To improve the humidity resistance of the water soluble core and optimize the process parameters applied in manufacturing of the water soluble core,a precipitation method and a two-level-three-full factorial central composite design were used,respectively.The properties of the cores treated by the precipitation method were compared with that without any treatment.Through a systematical study by means of both an environmental scanning electron microscope(ESEM) and an energy dispersive X-ray(EDX) analyzer,the results indicate that the hygroscopicity can be reduced by 20% and the obtained optimal process conditions for three critical control factors affecting the hygroscopicity are 0.2 g·mL-1 calcium chloride concentration,4% water concentration and 0 min ignition time.The porous surface coated by calcium chloride and the high humidity resistance products generated in the precipitation reaction between calcium chloride and potassium carbonate may contribute to the lower hygroscopicity. 展开更多
关键词 水溶性 沉淀法 高湿度 电阻 环境扫描电子显微镜 中心复合设计 最佳工艺条件 吸湿性能
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Water soluble components of PM_(10) in Chongqing, China 被引量:3
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作者 罗清泉 鲜学福 +1 位作者 陈刚才 杨清玲 《Chinese Journal Of Geochemistry》 EI CAS 2005年第2期155-157,共3页
The concentrations of water soluble ions (Na++, NH++-4, K++, Mg+{2+}, Ca+{2+}, NO+--3, Cl+-, and SO+{2-}-4) in PM-{10} samples collected on cellulose filters by a medium-volume cascade impactor were determined, which ... The concentrations of water soluble ions (Na++, NH++-4, K++, Mg+{2+}, Ca+{2+}, NO+--3, Cl+-, and SO+{2-}-4) in PM-{10} samples collected on cellulose filters by a medium-volume cascade impactor were determined, which were obtained from three kinds of areas in Chongqing: industrial area (Jiulongpo district), commercial and residential area (Jiangbei district) and background area (Jinyun Mountain in the Beibei district). The results showed that except for the background site, the annual average values of PM-{10} are 23%-61% higher than the national air quality standard (GradeⅡ) ({0.1} mg/m+3), even that the value of the control site is still 20% higher than American standard ({0.05} mg/m+3). This implied that serious pollution of fine particles occurred in Chongqing. Nine kinds of soluble ions in water of PM-{10} were analyzed by ion chromatography (IC) and the annual average concentrations follow the order of >>>, and >>>>. Their values were different in these areas: the industrial area>the commercial and living area>the control area. As for NH++-4, K++, Ca+{2+}, NO+--3 and SO+{2-}-4, their seasonal average concentrations show a similar variation trend: the values in spring and fall were higher than those in summer and winter. The seasonal average concentrations of , , and are much lower than those of other ions. However, the concentrations of changed more greatly in different seasons than those of the other three ions. Correlation coefficients showed that the three areas have been polluted by coal smoke and dust to different extents, while some local resources of pollution should be taken into consideration as well. 展开更多
关键词 水溶解离子 重庆 大气污染 硫氧化物 颗粒尺寸
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Preparation of Ultrafine Water-soluble Polymers Nanofiber Mats via Electrospinning 被引量:3
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作者 SUN Guo-en TENG Hong +2 位作者 ZHANG Chun-ling DOU Yan-li LI Yi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第2期318-322,共5页
A series of water-soluble polymers such as poly(ethylene oxide)(PEO), polyacrylamide(PAM) and poly(vinyl pyrrilidone)(PVP) was successfully prepared via the electrospinning of their aqueous solutions without... A series of water-soluble polymers such as poly(ethylene oxide)(PEO), polyacrylamide(PAM) and poly(vinyl pyrrilidone)(PVP) was successfully prepared via the electrospinning of their aqueous solutions without the use of a surfactant. The effects of solution properties on the electrospinning of PEO, PAM and PVP solutions were investigated. The viscosity of the solution, charge density carried by the jet, and the surface tension of the solution are the key factors that influence the morphology and diameter size of the fibers. The viscosity of the solution was measured on a modular compact rheometer. The morphology and the diameter size distribution of the fibers were observed under an environmental scanning electron microscope(ESEM). The results show that the diameters of the nanofibers electro spun from the solutions of these water soluble polymers were uniform and less than 300 nm. 展开更多
关键词 FIBER ELECTROSPINNING water-soluble polymer
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Research advances in antiplatelet activation of water soluble compounds in Salvia miltiorrhiza 被引量:5
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作者 Hai-gang WANG Rui WANG +2 位作者 Xiao-yue ZHAO Liang YU Guan-hua DU 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第4期302-302,共1页
Platelets are fragments of cytoplasm that are released from the mature megakaryocyte of the bone marrow.The main function of platelets is coagulation and hemostasis.Platelets play a central role in formation of pathol... Platelets are fragments of cytoplasm that are released from the mature megakaryocyte of the bone marrow.The main function of platelets is coagulation and hemostasis.Platelets play a central role in formation of pathological thrombosis.Many ischemic diseases are caused by excessive activa.tion of platelets,which can lead to thrombosis and death.Salvia miltiorrhiza Bunge,the dry roots and rhizomes of the Salvia miltiorrhiza plants,includes some water-soluble compounds,which play positive effects on diverse diseases such as neurodegenerative diseases,diabetic complications or cardiovas.cular diseases.In this paper,the components of the water-soluble in Salvia miltiorrhiza,as well as the applications in thrombotic diseases are summarized.The results show that water-soluble compounds include salvianolic acid A,salvianolic acid B,protocatechuic aldehyde,Danshensu,etc.The water-soluble compounds are applied to ischemic stroke,myocardial infarction and other diseases caused by thrombus.We also discussed the mechanisms of water-soluble compounds on the platelets based on our research results and the data obtained from references.The results indicate that water soluble compounds in Salvia miltiorrhiza play the antiplatelet and antithrombotic effects via different mechanisms,for example,salvianolic acid A inhibits platelet aggregation without promoting bleeding by increasing cAMP,inhibiting phosphoinositide 3-kinase(PI3K) and affecting GPCRs(G protein-coupled receptors) signaling path.ways;salvianolic acid B inhibit platelets as a P2Y12 antagonist and PDE inhibitor;Danshensu inhibits platelet activity may be related to inhibition of calcium influx.In conclusion,thrombotic diseases seriously affect human life and health.The existing antiplatelet drugs have some disadvantages.For example,aspirin may cause intracranial hemorrhage,and clopidogrel may play a slower role.Salvia miltiorrhiza as a traditional Chinese medicine has positive pharmacological activity and exerts antiplatelet aggrega.tion through different mechanisms.In the future,we will develop the new drugs which prevent and treat thrombotic diseases with the further study of the pharmacological effects and mechanisms of Salvia miltiorrhiza. 展开更多
关键词 血小板 心血管疾病 治疗方法 临床分析
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