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Pharmacokinetics of Controlled Release and Immediate Release Morphine Sulphate Tablets after a Single Dose and Multiple Doses in Chinese Volunteers
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作者 邓艳萍 王凯 +3 位作者 刘立京 刘静雯 蔡志基 楼雅卿 《Journal of Chinese Pharmaceutical Sciences》 CAS 1997年第4期39-42,共4页
The pharmacokinetics of morphine sulphate was studied in 10 Chinese healthy volunteers after a single oral dose. Blood samples were collected before and after administration of controlled release tablets (CRMS, 30 mg)... The pharmacokinetics of morphine sulphate was studied in 10 Chinese healthy volunteers after a single oral dose. Blood samples were collected before and after administration of controlled release tablets (CRMS, 30 mg) and immediate release tablets (IRMS, 20 mg). The plasma concentration of morphine was determined by GC MS. The pharmacokinetic parameters of controlled release tablets and immediate release tablets were calculated∶ C max was 19.38±3.80 and 21.27±6.21 ng/ml, t max was 2.36 ±0.37 h and 0.56±0.16 h, t 1/2β was 3.53±0.87 and 3.03±0.74 h, AUC was 145.15±17.65 and 93.08±16.65 ng/ml, respectively. The steady state plasma concentration of morphine sulphate in cancer patients after multiple doses was achieved, C max of CRMS and IRMS was 27.43±0.33 ng/ml and 22.68±0.16 ng/ml, C min of CRMS and IRMS was 19.45±1.44 ng/ml and 18.14±0.49 ng/ml, respectively. 展开更多
关键词 Controlled release morphine sulphate tablet Immediate release morphine sulphate tablet PHARMACOKINETICS Single dose Multiple doses GC MS
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Recovery of iron from waste ferrous sulphate by co-precipitation and magnetic separation 被引量:6
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作者 余旺 彭映林 郑雅杰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第1期211-219,共9页
Magnetite concentrate was recovered from ferrous sulphate by co-precipitation and magnetic separation. In co-precipitation process, the effects of reaction conditions on iron recovery were studied, and the optimal rea... Magnetite concentrate was recovered from ferrous sulphate by co-precipitation and magnetic separation. In co-precipitation process, the effects of reaction conditions on iron recovery were studied, and the optimal reaction parameters are proposed as follows: n(CaO)/n(Fe2+) 1.4:1, reaction temperature 80 ℃, ferrous ion concentration 0.4 mol/L, and the final mole ratio of Fe3+ to FJ+ in the reaction solution 1.9-2.1. In magnetic separation process, the effects of milling time and magnetic induction intensity on iron recovery were investigated. Wet milling played an important part in breaking the encapsulated magnetic phases. The results showed that the mixed product was wet-milled for 20 min before magnetic separation, the grade and recovery rate of iron in magnetite concentrate were increased from 51.41% and 84.15% to 62.05% and 85.35%, respectively. 展开更多
关键词 ferrous sulphate titanium dioxide magnetite concentrate CO-PRECIPITATION wet milling magnetic separation
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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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Attenuation of dextran sodium sulphate induced colitis in matrix metalloproteinase-9 deficient mice 被引量:9
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作者 Alfredo Santana Carlos Medina +5 位作者 Maria Cristina Paz-Cabrera Federico Díaz-Gonzalez Esther Farré Antonio Salas Marek W Radomski Enrique Quintero 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第40期6464-6472,共9页
AIM: To study whether matrix metalloproteinase-9 (MMP-9) is a key factor in epithelial damage in the dextran sodium sulphate (DSS) model of colitis in mice.METHODS: MMP-9-deficient and wild-type (wt) mice were given 5... AIM: To study whether matrix metalloproteinase-9 (MMP-9) is a key factor in epithelial damage in the dextran sodium sulphate (DSS) model of colitis in mice.METHODS: MMP-9-deficient and wild-type (wt) mice were given 5% DSS in drinking water for 5 d followed by recovery up to 7 d. On d 5 and 12 after induction of colitis, gelatinases, MMP-2 and MMP-9, were measured in homogenates of colonic tissue by zymography and Western blot, whereas tissue inhibitor of metalloproteinases (TIMPs) were measured by reverse zymography. The gelatinolytic activity was also determined in supernatants of polymorphonuclear leukocytes (PMN) isolated from mice blood. Moreover, intestinal epithelial cells were stimulated with TNF-α to study whether these cells were able to produce MMPs. Finally, colonic mucosal lesions were measured by microscopic examination. RESULTS: On d 5 of colitis, the activity of MMP-9 was increased in homogenates of colonic tissues (0.24 ± 0.1 vs 21.3 ± 6.4, P < 0.05) and PMN from peripheral blood in wt (0.5 ± 0.1 vs 10.4 ± 0.7, P < 0.05), but not in MMP-9-deficient animals. The MMP-9 activity was also up-regulated by TNF-α in epithelial intestinal cells (2.5 ± 0.5 vs 14.7 ± 3.0, P < 0.05). Although colitis also led to increase of TIMP-1 activity, the MMP-9/TIMP-1 balance remained elevated. Finally, in the MMP-9-deficient colitic mice both the extent and severity of intestinal epithelialinjury were significantly attenuated when compared with wt mice. CONCLUSION: We conclude that DSS induced colitis is markedly attenuated in animals lacking MMP-9. This suggests that intestinal injury induced by DSS is modu-lated by MMP-9 and that inhibition of this gelatinase may reduce inflammation. 展开更多
关键词 Matrix metalloproteinases MMP-9-deficient Dextran sodium sulphate Inflammatory bowel disease Experimental colitis
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Carboniferous Mixed Terrigenous Clastic, Carbonate and Sulphate Sediments in the Bachu Area, Xinjiang 被引量:4
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作者 XIAO Chuantao PAN Yuntang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第3期341-347,共7页
The Carboniferous system in the Xiaohaizi area, Bachu County, Xinjiang Uygur Autonomous Region, composed of typical mixed terrigenous clastic, carbonate and sulphate sediments, was mainly deposited in the tidal flat a... The Carboniferous system in the Xiaohaizi area, Bachu County, Xinjiang Uygur Autonomous Region, composed of typical mixed terrigenous clastic, carbonate and sulphate sediments, was mainly deposited in the tidal flat and lagoon environments. The mixed sediments occur as the following eleven types: 1. limestone intercalated with siltstone; 2. interbeds of shale and limestone; 3. gypsolyte interbedded with limestone; 4. gypsolyte intercalated with siltstone; 5. gypsolyte interbedded with shale; 6. gypsolyte intercalated with siltstone, limestone and dolomite; 7. siltstone interbedded with gypsolyte and limestone; 8. terrigenous detritus scattered in carbonate matrix; 9. carbonate as cement in clastic rocks; 10. mixed sediments of carbonate and terrigenous mud; 11. mixed sediments of carbonate grains with terrigenous sand. Based on the analysis of the dynamic mechanism of mixed sediments, it is believed that these types of mixed sediments in the study area were controlled by climate, sea level change and sources of sediments. 展开更多
关键词 terrigenous DETRITUS CARBONATE sulphate (gypsolyte) MIXED SEDIMENTS CARBONIFEROUS strata Xinjiang.
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Extraction of aluminium as aluminium sulphate from thermal power plant fly ashes 被引量:5
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作者 Seoul SANGITA Niva NAYAK Chitta Ranjan PA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第9期2082-2089,共8页
Valuable metal extraction technology from thermal power plant fly ash is limited.In the present study,aluminium is extracted from fly ash as highly pure aluminium sulphate(>99.0%)by leaching with sulphuric acid,fol... Valuable metal extraction technology from thermal power plant fly ash is limited.In the present study,aluminium is extracted from fly ash as highly pure aluminium sulphate(>99.0%)by leaching with sulphuric acid,followed by pre-concentration and successive crystallization.Two types of fly ashes from different sources,i.e.,Talcher Thermal Power Station(TTPS)and Vedanta Aluminium Company Limited(VAL)were chosen for comparative study on the extraction of aluminium as aluminium sulphate.The product is characterized by powder X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR)and thermogravimetric analysis(TGA).Purity of aluminium sulphate was also investigated by inductively coupled plasma?optical emission spectrometry(ICP?OES).The extraction efficiency of aluminium depends on the varied solid-to-liquid ratio(fly ash:18mol/L H2SO4,g/mL)and particle size of fly ashes.Physico-chemical analysis indicates that the obtained product is Al2(SO4)3·18H2O,having low iron content(0.08%). 展开更多
关键词 fly ash sulphuric acid aluminium sulphate LEACHING solid-to-liquid ratio particle size
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Molecular Dynamics Simulation on Scale Inhibition Mechanism of Polyepoxysuccinic Acid to Calcium Sulphate 被引量:5
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作者 Jian-ping Zeng Feng-he Wang +1 位作者 Chen Zhou Xue-dong Gong 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第2期219-225,I0004,共8页
Molecular dynamics simulation has been performed to simulate the interaction between PESA and the (001) face of anhydrite crystal CaSO4 at different temperatures with the presence of various number of H2O molecules.... Molecular dynamics simulation has been performed to simulate the interaction between PESA and the (001) face of anhydrite crystal CaSO4 at different temperatures with the presence of various number of H2O molecules. The results show that PESA can effectively prevent the growth of CaSO4 scale at 323-343 K. At the same temperature, the binding energy between PESA and the (001) face of CaSO4 for systems with various number of H2O has the order of E-bind(OH2O)〉Ebind(200-400H2O)〉E, bind(lOOH2O). For the same system at different temperatures the binding energies are close and are mainly contributed from the Coulomb interaction, including ionic bonds. The bonds are formed between the calcium atoms of anhydrite scale crystal and the Hydrogen bonds are formed between the O oxygen atoms of the carboxyl group of PESA. atoms of the carboxyl group of PESA and the H atoms of H2O. van der Waals interaction is conducive to the stability of the system of PESA, H2O, and CaSO4. The radial distribution functions of O(carbonyl of PESA)-H(H2O), O(CaSO4)-H(H2O), and O(CaSO4)-H(PESA) imply that solvents have effects on the anti-scale performance of PESA to CaSO4. 展开更多
关键词 Polyepoxysuccinic acid Calcium sulphate Molecular dynamics Binding en-ergy Radial distribution function
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Leaching kinetics of low-grade copper ore with high-alkality gangues in ammonia-ammonium sulphate solution 被引量:5
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作者 LIU Zhi-xiong YIN Zhou-lan +1 位作者 HU Hui-ping CHEN Qi-yuan 《Journal of Central South University》 SCIE EI CAS 2012年第1期77-84,共8页
The leaching kinetics of low-grade copper ore with high-alkality gangues was studied in ammonia-ammonium sulphate solution.The main parameters,such as ammonia and ammonium sulphate concentrations,particle size,solid-t... The leaching kinetics of low-grade copper ore with high-alkality gangues was studied in ammonia-ammonium sulphate solution.The main parameters,such as ammonia and ammonium sulphate concentrations,particle size,solid-to-liquid ratio and reaction temperature,were chosen in the experiments.The results show that the increase of temperature,concentrations of ammonia and ammonium sulphate is propitious to the leaching rate of copper ore.The leaching rate increases with the decrease of particle size and solid-to-liquid ratio.The leaching rate is controlled by the diffusion through the ash layer and the activation energy is determined to be 25.54 kJ/mol.A semi-empirical equation was proposed to describe the leaching kinetics. 展开更多
关键词 leaching kinetics ammonia-ammonium sulphate solution low-grade copper ore high-alkality gangues
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Mechanical Properties of Lime-Fly Ash-Sulphate Aluminum Cement Stabilized Loess 被引量:5
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作者 Liang Jia Chunxiang Li Jian Guo 《Journal of Renewable Materials》 SCIE EI 2020年第10期1357-1373,共17页
Lime-fly ash stabilized loess has a poor early strength,which results in a later traffic opening time when it is used as road-base materials.Consideration of the significant early strength characteristics of sulphate ... Lime-fly ash stabilized loess has a poor early strength,which results in a later traffic opening time when it is used as road-base materials.Consideration of the significant early strength characteristics of sulphate aluminum cement(SAC),it is always added into the lime-fly ash mixtures to improve the early strength of stabilized loess.However,there is a scarcity of research on the mechanical behavior of lime-fly ash-SAC stabilized loess and there is a lack of quantitative evaluation of loess stabilized with binder materials.This research explored the effects of the amount of binder materials,curing time and porosity on the unconfined compressive strength(UCS),splitting tensile strength(STS),cohesion(c)and friction angle(φ)of lime-fly ash-SAC stabilized loess by a series of unconfined compressive tests(UCT)and splitting tensile tests(STT).The results indicate that an increase in curing time and a decrease in porosity lead to a continuous increase in the UCS and STS for lime-fly ash-SAC stabilized loess.The addition of SAC has a prominent enhancement in the early strength of lime-fly ash-SAC stabilized loess.When the curing time,porosity,and binder content were constant,the UCS and STS increase with increasing SAC content;For a stabilized loess with 30%binder content and 5%SAC content after 1 day of curing,the UCS was greater than 0.7 MPa,which meets the requirement of opening traffic,so lime-fly ash-SAC stabilized loess could be used as an excellent maintenance material for road-base;In accordance with the analysis of testing data,empirical relationships between the UCS and STS of lime-fly-SAC stabilized loess and key effect factors(binder materials content,curing time and porosity)were developed,which can provide references for reasonably selecting the amount of binder materials,compaction degree and curing period to meet the required strength of practical engineering.Finally,based on the Mohr-Coulomb theory and the above empirical relationships,a simpler method for calculating the c andφof stabilized loess was proposed,with which,the shear strength parameters can be determined only by UCT or STT. 展开更多
关键词 LOESS sulphate aluminum cement unconfined compressive strength splitting tensile strength
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Selective debenzylation of benzyl esters by silica-supported sodium hydrogen sulphate 被引量:3
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作者 Yan Wei Hu Li Zuo +1 位作者 De Yong Ye Wen Hu Duan 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第10期1157-1160,共4页
A new debenzylation of benzyl esters by silica-supported sodium hydrogen sulfate is described. The debenzylation could be achieved selectively and efficiently in good to excellent yields without affecting sensitive fu... A new debenzylation of benzyl esters by silica-supported sodium hydrogen sulfate is described. The debenzylation could be achieved selectively and efficiently in good to excellent yields without affecting sensitive functional groups such as nitro, unsaturated bonds, and ethyl ester. 展开更多
关键词 DEBENZYLATION Benzyl esters Silica-supported sodium hydrogen sulphate
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Anti-tumor necrosis factor α therapy associates to type 17 helper T lymphocytes immunological shift and significant microbial changes in dextran sodium sulphate colitis 被引量:2
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作者 Valentina Petito Cristina Graziani +13 位作者 Loris R Lopetuso Marco Fossati Alessandra Battaglia Vincenzo Arena Domenico Scannone Gianluca Quaranta Andrea Quagliariello Federica Del Chierico Lorenza Putignani Luca Masucci Maurizio Sanguinetti Alessandro Sgambato Antonio Gasbarrini Franco Scaldaferri 《World Journal of Gastroenterology》 SCIE CAS 2019年第12期1465-1477,共13页
BACKGROUND Anti-tumor necrosis factor α(TNFα) represents the best therapeutic option to induce mucosal healing and clinical remission in patients with moderate-severe ulcerative colitis. On the other side gut microb... BACKGROUND Anti-tumor necrosis factor α(TNFα) represents the best therapeutic option to induce mucosal healing and clinical remission in patients with moderate-severe ulcerative colitis. On the other side gut microbiota plays a crucial role in pathogenesis of ulcerative colitis but few information exists on how microbiota changes following anti-TNFα therapy and on microbiota role in mucosal healing.AIM To elucidate whether gut microbiota and immune system changes appear following anti TNFα therapy during dextran sulfate sodium(DSS) colitis.METHODS Eighty C57 BL/6 mice were divided into four groups: "No DSS", "No DSS + antiTNFα", "DSS" and "DSS + anti-TNFα". "DSS" and "DSS + anti-TNFα" were treated for 5 d with 3% DSS. At day 3, mice whithin "No DSS+anti-TNFα" and"DSS+anti-TNFα" group received 5 mg/kg of an anti-TNFα agent. Forty mice were sacrificed at day 5, forty at day 12, after one week of recovery post DSS. The severity of colitis was assessed by a clinical score(Disease Activity Index), colon length and histology. Bacteria such as Bacteroides, Clostridiaceae, Enterococcaceae and Fecalibacterium prausnitzii(F. prausnitzii) were evaluated by quantitative PCR.Type 1 helper T lymphocytes(Th1), type 17 helper T lymphocytes(Th17) and CD4+ regulatory T lymphocytes(Treg) distributions in the mesenteric lymph node(MLN) were studied by flow cytometry.RESULTS Bacteria associated with a healthy state(i.e., such as Bacteroides, Clostridiaceae and F. prausnitzii) decreased during colitis and increased in course of anti-TNFαtreatment. Conversely, microorganisms belonging to Enterococcaceae genera,which are linked to inflammatory processes, showed an opposite trend.Furthermore, in colitic mice treated with anti-TNFα microbial changes were associated with an initial increase(day 5 of the colitis) in Treg cells and a consequent decrease(day 12 post DSS) in Th1 and Th17 frequency cells. Healthy mice treated with anti-TNFα showed the same histological, microbial and immune features of untreated colitic mice. "No DSS + anti-TNFα" group showed a lymphomononuclear infiltrate both at 5 th and 12 th d at hematoxylin and eosin staining, an increase of in Th1 and Th17 frequency at day 12, an increase of Enterococcaceae at day 5, a decrease of Bacteroides and Clostridiaceae at day 12.CONCLUSION Anti-TNFα treatment in experimental model of colitis improves disease activity but it is associated to an increase in Th17 pathway together with gut microbiota alteration. 展开更多
关键词 Gut microbiota DEXTRAN sodium sulphate COLITIS Immune system T cells MESENCHYMAL lymphnode Tumor NECROSIS factor α
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Assessment of deterioration in RHA-concrete due to magnesium sulphate attack 被引量:2
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作者 G.A. Habeeb H.B. Mahmud N.B.A.A. Hamid 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2010年第6期691-696,共6页
The assessment of magnesium sulphate attack on concretes containing rice husk ash (RHA, 20wt% of the cementitious materials) with various average particle sizes was investigated. The total cementitious materials wer... The assessment of magnesium sulphate attack on concretes containing rice husk ash (RHA, 20wt% of the cementitious materials) with various average particle sizes was investigated. The total cementitious materials were 390 kg and the water-to-binder ratio (W/B) was 0.53 for all mixtures. Specimens were initially cured in water for 7 d and then immersed in the 3wt% magnesium sulphate solution for up to 111 d of exposure. The specimens were subjected to drying-wetting cycles to accelerate sulphate attack. In addition to the visual monitoring of the specimens, the concrete specimens were subsequently tested for compressive strength, dynamic modulus of elasticity, and length and mass changes. The results show that the specimens exposed to sulphate attack exhibit higher strength and dynamic modulus than those kept in water. The length change is negligible and can be attributed to the normal swelling of concrete. On the other hand, concretes suffers mass loss and surface spalling and softening; the fine RHA-concrete results in a better resistance. For the accelerated sulphate attack method used in this study, mass change and visual monitoring are recommended for assessing the deterioration degree and the effectiveness of supplementary cementitious materials to resist sulphate attack. 展开更多
关键词 CONCRETES POZZOLAN ETTRINGITE rice husk ash (RHA) magnesium sulphate
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Potassium sulphate induces resistance of rice against the rootknot nematode Meloidogyne graminicola 被引量:2
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作者 LIU Mao-Yan PENG De-liang +9 位作者 SU Wen XIANG Chao JIAN Jin-zhuo ZHAO Jie PENG Huan LIU Shi-ming KONG Ling-an DAI Liang-ying HUANG Wen-kun LIU Jing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第11期3263-3277,共15页
Potassium(K),an important nutrient element,can improve the stress resistance/tolerance of crops.The application of K in resisting plant-parasitic nematodes shows that the K treatment can reduce the occurrence of nemat... Potassium(K),an important nutrient element,can improve the stress resistance/tolerance of crops.The application of K in resisting plant-parasitic nematodes shows that the K treatment can reduce the occurrence of nematode diseases and increase crop yield.However,data on K_(2)SO_(4)induced rice resistance against the root-knot nematode Meloidogyne graminicola are still lacking.In this work,K_(2)SO_(4)treatment reduced galls and nematodes in rice plants and delayed the development of nematodes.Rather than affecting the attractiveness of roots to nematodes and the morphological phenotype of giant cells at feeding sites,such an effect is achieved by rapidly priming hydrogen peroxide(H_(2)O_(2))accumulation and increasing callose deposition.Meanwhile,galls and nematodes in rice roots were more in the potassium channel OsAKT11 and transporter OsHAK5 gene-deficient plants than in wild-type,while the K_(2)SO_(4)-induced resistance showed weaker in the defective plants.In addition,during the process of nematode infection,the expression of jasmonic acid(JA)/ethylene(ET)/brassinolide(BR)signaling pathway-related genes and pathogenesis-related(PR)genes OsPR1 a/OsPR1 b was up-regulated in rice after K_(2)SO_(4)treatment.In conclusion,K_(2)SO_(4)induced rice resistance against M.graminicola.The mechanism of inducing resistance was to prime the basal defense and required the participation of the K^(+)channel and transporter in rice.These laid a foundation for further study on the mechanism of rice defense against nematodes and the rational use of potassium fertilizer on improving rice resistance against nematodes in the field. 展开更多
关键词 RICE Meloidogyne graminicola potassium sulphate induced resistance H_(2)O_(2) CALLOSE potassium channel and transporter
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Ultrasonic Studies of 4-Aminobutyric Acid in Aqueous Salbutamol Sulphate Solutions at Different Temperatures 被引量:2
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作者 K.Rajagopal S.S.Jayabalakrishnan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第4期659-666,共8页
Ultrasonic speeds of 4-aminobutyric acid in 0.0041,0.0125 and 0.0207 mol·kg^-1 aqueous salbutamol sulphate(SBS) solutions are measured at 308.15,313.15 and 318.15 K.Isentropic compressibility kS,change in isent... Ultrasonic speeds of 4-aminobutyric acid in 0.0041,0.0125 and 0.0207 mol·kg^-1 aqueous salbutamol sulphate(SBS) solutions are measured at 308.15,313.15 and 318.15 K.Isentropic compressibility kS,change in isentropic compressibility△k S,relative change in isentropic compressibility( △kS /kS^0) ,apparent molal compressibility kφ,limiting apparent molal compressibility kφ^0 ,transfer limiting apparent molal compressibility k φ^0,hydration number nH,pair and triplet interaction parameters kAS,kASS are estimated.The above parameters are used to interpret the solute-solute and solute-solvent interactions of 4-aminobutyric acid in the aqueous salbutamol sulphate solutions. 展开更多
关键词 ultrasonic speed isentropic compressibility limiting apparent molal compressibility hydration number salbutamol sulphate
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Study on Removal of Trace Lead from Nickel Sulphate Solution by Ion-exchange Method 被引量:2
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作者 XIAO Lian-sheng ZHANG Gui-qing +4 位作者 ZHANG Qi-xiu GONG Bo-fan MA Jing-xia LI Ji-zhong Zhu Rui-lun 《Journal of Central South University》 SCIE EI CAS 2000年第4期191-193,共3页
By comparing the adsorption capacity of several kinds of resins, D363 resin is regarded as the most suitable one for removing lead from nickel sulphate electrolyte. The effects of pH, temperature and contact time on e... By comparing the adsorption capacity of several kinds of resins, D363 resin is regarded as the most suitable one for removing lead from nickel sulphate electrolyte. The effects of pH, temperature and contact time on exchange adsorption during removing trace lead from industrial nickel sulphate solution with D363 large pore weak alkali anion exchange resin are discussed. Optimum conditions of adsorption of lead from nickel electrolyte by D363 resin are at room temperature, pH 1 2, contact time 30 min. 展开更多
关键词 ion-exchange nickel sulphate LEAD
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Bioassay-Guided Extraction of Crude Fucose-Containing Sulphated Polysaccharides from Sargassum fusiforme with Response Surface Methodology 被引量:2
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作者 FU Zhifei LI Haihua +4 位作者 LIU Hongbing HU Shuman LI Yueying WANG Mengxue GUAN Huashi 《Journal of Ocean University of China》 SCIE CAS 2016年第3期533-540,共8页
The response surface methodology(RSM) combined with bioassays was employed to optimize the extraction process of crude fucose-containing sulphated polysaccharides(c FCSP) from Sargassum fusiforme. The central composit... The response surface methodology(RSM) combined with bioassays was employed to optimize the extraction process of crude fucose-containing sulphated polysaccharides(c FCSP) from Sargassum fusiforme. The central composite design(CCD) was used with four variables, five levels, and four responses. The four variables were p H value of hydrochloric acid solution, extraction temperature(℃), ratio of liquid to raw material(m L g^(-1)), and extraction time(h), respectively. Chemical and bioassay indices were used in combination as the response parameters, which included the yield of c FCSP, fucose content, proliferation rate of spleen cells, and lipopolysaccharide-induced proliferation of splenocytes. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis, and examined using the appropriate statistical methods. The best extraction conditions were as follows: the p H value of hydrochloric acid solution was 3.50; the extraction temperature was 100℃; the ratio of liquid to raw material was 15.00 m L g^(-1) and the extraction time was 2.50 h. The experimental yield was close to the predicted from the model. The extract could promote spleen lymphocyte proliferation, especially the lipopolysaccharide-induced lymphocyte proliferation in vitro, which suggested that its immunomodulatory effect on B lymphocytes. Therefore, c FCSP extracted from S. fusiforme could be utilized as an immunostimulant in functional foods and pharmaceutical industry in future. 展开更多
关键词 crude fucose-containing sulphated polysaccharides Sargassum fusiforme response surface methodology immuno-modulatory
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Identification, Characterization and Evaluation of Crystal Forms of Quinine Sulphate 被引量:3
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作者 Maninder Karan Renu Chadha +1 位作者 Kunal Chadha Poonam Arora 《Pharmacology & Pharmacy》 2012年第2期129-138,共10页
Crystal engineering concept has been utilized to modify the physico-chemical parameters of a naturally occurring alkaloid, quinine sulphate, by exploring its H-bond interactions to generate different forms. Quinine su... Crystal engineering concept has been utilized to modify the physico-chemical parameters of a naturally occurring alkaloid, quinine sulphate, by exploring its H-bond interactions to generate different forms. Quinine sulphate is found to exist in four different crystal forms. The Forms I and II depict endo/exo events suggesting conversion of metastable low melting forms to higher melting and stable form indicated by sharp melting endotherms. The low melting form IL is found to be monotropically related to high melting Form IH while low melting Form IIL is enantiotropically related to high melting Form IIH. The Form III and IV showed broad endotherms accompanied by mass loss in TGA prior to melting indicating the existence of solvatomorphism. The solvent molecules are tightly bound in the crystal lattice of the drug molecules which is shown by high values of the binding energies of the solvents in these two forms. The enthalpy of solution was found to be endothermic for all the forms which followed the order: Form O > Form II > Form III > Form I > Form IV and is further related to the lattice energy suggesting Form II to be least crystalline. The solubility for Form II was found to be highest with maximum release rate in dissolution studies. The effectiveness of new polymorphic forms was confirmed by performing in vivo antimalarial activity against P. berghei infection. The studies have shown an increase in antimalarial activity of Form IV concluding a successful development of new polymorphic form. 展开更多
关键词 QUININE sulphate ENTHALPY POLYMORPHS SOLVATES CRYSTALS
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Barium, Calcium and Sodium, Cyanide, Phosphate and Sulphate Contents of Groundwater in Some Ika Communities of Delta State, Nigeria 被引量:2
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作者 Hector H. Oyem Ifeanyi M. Oyem Esther N. Obiwulu 《Journal of Geoscience and Environment Protection》 2017年第8期89-98,共10页
Barium, calcium, sodium, cyanide, phosphate and sulphate and contents of groundwater in Boji-Boji (BB) area and suburbs of Ika land, Delta State, Nigeria were studied. Groundwater is the predominant source of water fo... Barium, calcium, sodium, cyanide, phosphate and sulphate and contents of groundwater in Boji-Boji (BB) area and suburbs of Ika land, Delta State, Nigeria were studied. Groundwater is the predominant source of water for inhabitants of these communities without any form of treatment. 55 borehole water sites spread within these five sample sub-areas. The metal ions were analyzed using Solar Unicam flame Atomic Absorption Spectrophotometer. Sulphate, phosphate, and cyanide contents were determined by colorimetric method. Results indicate the presence of sodium, calcium, sulphate, and phosphate. However, barium and cyanide were below detection limit. Secondly, there was a relatively higher proportion of calcium and sulphate than sodium and phosphate in its aquifer. Thirdly, a mean ratio value of 0.018 and 0.158 was observed for the ratios of Na+/Ca2+ and ?respectively. Fourthly, sodium showed good correlation with all the other parameters. Finally, nearly all the studied parameters have concentrations below the maximum contaminant levels of the World Health Organization (WHO), invariably inferring that the water is wholesome with respect to the analytes. However, concern still remains from a health point of view on the sodium concentrations in many sample areas. 展开更多
关键词 Ground Water SODIUM CALCIUM sulphate and PHOSPHATE
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Chemical and Electrochemical Characterization of Artifi cial Sulphate Patina on Bronze 被引量:1
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作者 毛样武 NIE Dunwei MOMBELLO Domenico 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第3期585-589,共5页
Copper patinas are generally regarded as aesthetically pleasing and are supposed to protect copper against further corrosion. The preparation of artificial sulphate patina on bronzes has been realized by immersing the... Copper patinas are generally regarded as aesthetically pleasing and are supposed to protect copper against further corrosion. The preparation of artificial sulphate patina on bronzes has been realized by immersing the bronze into CuSO4 solution. The effect of immersion time on the formation of the patina has been investigated. The sulphate patina obtained with immersion time of 500 h in CuSO4 solution consists of fiat area and crystals. The flat area in the patina is mainly made of cuprite, whereas the crystals are mainly composed of brochantite. The electrochemical measurement of sulphate patina in simulated acid rain with pH 3.1 shows that the protective effectiveness of patina decreases with time and the dissolution of patina is the key factor leading to the degradation of patina. The investigation of the formation mechanism of sulphate patina shows that the cuprite layer forms on the surface of bronze in the initial patination. Then, crystal brochantite grows on the surface of cuprite by the oxidation of cuprite and the incorporation of CuSO4 solution. 展开更多
关键词 artificial sulphate patina BRONZE electrochemical characterization
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Damage Evolution of Concrete under the Actions of Stray Current and Sulphate 被引量:4
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作者 ZHANG Lu WEN Bo +1 位作者 NIU Ditao JI Zhiyuan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2021年第4期578-587,共10页
Based on the mechanism of stray current generation in underground structures,the concrete durability test device for stray current and sulphate in typical soil environment was designed to study the damage of concrete ... Based on the mechanism of stray current generation in underground structures,the concrete durability test device for stray current and sulphate in typical soil environment was designed to study the damage of concrete under the action of stray current and sulphate.The deterioration law of concrete under the action of stray current and sulphate was studied by microscopic techniques such as scanning electron microscopy (SEM) and X-ray diffraction (XRD).The microstructure of corroded concrete was observed to determine the phase composition of erosion products.The damage performances such as quality,strength,and dynamic elastic mode of corroded concrete were performed.The experimental results show that,under the action of stray current,the products of sulfate-eroded concrete are mainly gypsum,ettringite,and thaumasite;the stray current accelerates the hydration process of cement and the erosion of concrete by sulfate;when the concrete pores are filled with the erosion product,there is an increase of approximately 10% in the concrete compressive strength and dynamic elastic modulus;and the concrete compressive strength is more sensitive to the stray current electrification period than the current intensity. 展开更多
关键词 Damage Evolution of Concrete under the Actions of Stray Current and sulphate
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