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Lipid Production,Oxidative Status,Antioxidant Enzymes and Photosynthetic Efficiency of Coccomyxa chodatii SAG 216-2 in Response to Calcium Oxide Nanoparticles
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作者 Huwida A.A.Abdel-Kader Naeima Yousef +1 位作者 Mohammad Anwar Hossain Mona F.A.Dawood 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第7期1955-1974,共20页
The extensive use of nanoparticles(NPs)in diverse applications causes their localization to aquatic habitats,affecting the metabolic products of primary producers in aquatic ecosystems,such as algae.Synthesized calciu... The extensive use of nanoparticles(NPs)in diverse applications causes their localization to aquatic habitats,affecting the metabolic products of primary producers in aquatic ecosystems,such as algae.Synthesized calcium oxide nanoparticles(CaO NPs)are of the scarcely studied NPs.Thus,the current work proposed that the exposure to CaO NPs may instigate metabolic pathway to be higher than that of normally growing algae,and positively stimulate algal biomass.In this respect,this research was undertaken to study the exposure effect of CaO NPs(0,20,40,60,80,and 100μg mL^(−1))on the growth,photosynthesis,respiration,oxidative stress,antioxidants,and lipid production of the microalga Coccomyxa chodatii SAG 216-2.The results showed that the algal growth concomitant with chlorophyll content,photosynthesis,and calcium content increased in response to CaO NPs.The contents of biomolecules such as proteins,amino acids,and carbohydrates were also promoted by CaO NPs with variant degrees.Furthermore,lipid production was enhanced by the applied nanoparticles.CaO NPs induced the accumulation of hydrogen peroxide,while lipid peroxidation was reduced,revealing no oxidative behavior of the applied nanoparticles on alga.Also,CaO NPs have a triggering effect on the antioxidant enzymes such as superoxide dismutase,catalase,ascorbate peroxidase,and guaiacol peroxidase.The results recommended the importance of the level of 60μg mL^(−1) CaO NPs on lipid production(with increasing percentage of 65%compared to control)and the highest dry matter acquisition of C.chodatii.This study recommended the feasibility of an integrated treatment strategy of CaO NPs in augmenting biomass,metabolic up-regulations,and lipid accumulation in C.chodatii. 展开更多
关键词 calcium oxide nanoparticles Coccomyxa chodatii GROWTH hydrogen peroxide metabolic products
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Effects of Calcium Oxide on Physicochemical Properties of Spray-dried Bayberry Powder
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作者 宋贤聚 《Agricultural Science & Technology》 CAS 2015年第8期1766-1768,1774,共4页
[Objective] Effects of different contents of calcium oxide on physicochemi- cal properties of spray-dried bayberry powder were studied. [Method] Bayberry pow- der produced from bayberry juice adding 0, 2 and 4 g/L cal... [Objective] Effects of different contents of calcium oxide on physicochemi- cal properties of spray-dried bayberry powder were studied. [Method] Bayberry pow- der produced from bayberry juice adding 0, 2 and 4 g/L calcium oxide using the spray drying technique has been selected. The physicochemical properties of the spray-dried bayberry powder were investigated by determining moisture content, colour, apparent density, wettability, angle of repose and moisture absorption rate of bayberry powder. [Result] The results showed that the content of calcium oxide had a significant effect on the moisture content and colour of bayberry powder. Effects of different contents of calcium oxide on the apparent density of spray-dried bayber- ry powder were not obvious. Adding calcium oxide had a significant effect on the wettability, angle of repose and moisture absorption rate of spray-dried bayberry powder, nevertheless, there was not obvious difference on these properties between adding 2 and 4 g/L calcium oxide. [Conclusion] The results confirmed that the con- tent of calcium oxide had a significant effect on the properties of spray-dried bay- berry powder. 展开更多
关键词 calcium oxide SPRAY-DRYING Bayberry powder Physicochemical proper-ties
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Cross-talk between calcium-calmodulin and nitric oxide in abscisic acid signaling in leaves of maize plants 被引量:6
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作者 Jianrong Sang Aying Zhang Fan Lin Mingpu Tan Mingyi Jiang 《Cell Research》 SCIE CAS CSCD 2008年第5期577-588,共12页
Using pharmacological and biochemical approaches, the signaling pathways between hydrogen peroxide (H2O2), calcium (Ca^2+)-calmodulin (CAM), and nitric oxide (NO) in abscisic acid (ABA)-induced antioxidant ... Using pharmacological and biochemical approaches, the signaling pathways between hydrogen peroxide (H2O2), calcium (Ca^2+)-calmodulin (CAM), and nitric oxide (NO) in abscisic acid (ABA)-induced antioxidant defense were investigated in leaves of maize (Zea mays L.) plants. Treatments with ABA, H2O2, and CaCl2 induced increases in the generation of NO in maize mesophyll cells and the activity of nitric oxide synthase (NOS) in the cytosolic and microsomal fractions of maize leaves. However, such increases were blocked by the pretreatments with Ca^2+ inhibitors and CaM antagonists. Meanwhile, pretreatments with two NOS inhibitors also suppressed the Ca^2+-induced increase in the production of NO. On the other hand, treatments with ABA and the NO donor sodium nitroprusside (SNP) also led to increases in the concentration of cytosolic Ca^2+ in protoplasts of mesophyll cells and in the expression of calmodulin 1 (CaM1) gene and the contents of CaM in leaves of maize plants, and the increases induced by ABA were reduced by the pretreatments with a NO scavenger and a NOS inhibitor. Moreover, SNP-induced increases in the expression of the antioxidant genes superoxide dismutase 4 (SOD4), cytosolic ascorbate peroxidase (cAPX), and glutathione reductase 1 (GR1) and the activities of the chloroplastic and cytosolic antioxidant enzymes were arrested by the pretreatments with Ca^2+ inhibitors and CaM antagonists. Our results suggest that Ca^2+-CaM functions both upstream and downstream of NO production, which is mainly from NOS, in ABA- and H2O2-induced antioxidant defense in leaves of maize plants. 展开更多
关键词 abscisic acid antioxidant defense CALMODULIN cytosolic calcium nitric oxide nitric oxide synthase Zea mays
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Effect of Calcium Oxide Additive on the Performance of Iron Oxide Sorbent for High-Temperature Coal Gas Desulfurization 被引量:7
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作者 Huiling Fan Kechang Xie Ju Shangguan Fang Shen Chunhu Li 《Journal of Natural Gas Chemistry》 CAS CSCD 2007年第4期404-408,共5页
The effect of calcium oxide additive in iron oxide sorbent for hot gas desulfurization was investigated by XRD and TPR techniques.XRD characterization showed that CaO was highly dispersed after the calcination of sorb... The effect of calcium oxide additive in iron oxide sorbent for hot gas desulfurization was investigated by XRD and TPR techniques.XRD characterization showed that CaO was highly dispersed after the calcination of sorbents.Calcium sulfate formed in the desulfurization was decomposed and regenerated to CaO by reacting with CO before the next sulfidation process.Calcium participated in every sulfidation/regeneration cycle and contributed to the enhancement of sulfur capacity.The TPR results showed that the reduction temperature of the sorbent increased with the increase of the content of calcium.Calcium played a role of retarding reduction.Therefore,the addition of calcium oxide additive will benefit the utilization of iron oxide sorbent in strongly reducing atmospheres. 展开更多
关键词 calcium oxide iron oxide sorbent high temperature desulfurization
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Effect of Barium Oxide on the Formation and Coexistence of Tricalcium Silicate and Calcium Sulphoaluminate 被引量:1
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作者 陈琳 沈晓冬 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第3期457-461,共5页
Formation and coexistence of tricalciurn silicate (C3S) and calcium sulphoaluminate ( C4 A3S^- ) minerals in Portland cement clinker containing calcium sulphoaluminate were investigated. Thef-CaO content, mineral ... Formation and coexistence of tricalciurn silicate (C3S) and calcium sulphoaluminate ( C4 A3S^- ) minerals in Portland cement clinker containing calcium sulphoaluminate were investigated. Thef-CaO content, mineral composite and formation of mineral in the clinker were analyzed respectively by chemical analysis, differential scanning calorimetry(DSC) and X-ray diffraction. The results show that, adding a suitable amount of BaO can improve the burnability of raw meal and promote the f-CaO absorption. Tricalcium silicate and calcium sulphoaluminate minerals can form and coexist in clinkers at 1 234-1 317 ℃ by the addition of BaO to the raw meal. A suitable amount of BaO expanded the coexistence temperature of two minerals by 58 ℃. 展开更多
关键词 barium oxide tricalcium silicate calcium sulphoaluminate coexistence temperature
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Styrene epoxidation with hydrogen peroxide over calcium oxide catalysts prepared from various precursors 被引量:1
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作者 Qingming Gu Dan Han +1 位作者 Lei Shi Qi Sun 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第4期452-458,共7页
A series of CaO samples were prepared by calcination of commercially available and synthesis of calcium salt precursors such as calcium acetate, carbonate, hydroxide and oxalate etc. CaO samples were found to be effec... A series of CaO samples were prepared by calcination of commercially available and synthesis of calcium salt precursors such as calcium acetate, carbonate, hydroxide and oxalate etc. CaO samples were found to be effective for the epoxidation of styrene using hydrogen peroxide as an oxidant in the presence of acetonitrile. To determine the influence of the physicochemical properties and surface basicity on the catalytic activity, the prepared CaO samples were characterized using thermogravimetry (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM), N2-adsorption and temperature-programmed desorption of CO2 (CO2-TPD). The results indicate that the amounts of very strong basic sites and high basicity strength on CaO sample are key factors for its excellent catalytic performance. In contrast, the surface area, porosity and the surface structure of CaO sample have a relatively minor effect on the catalytic activity. CaO sample, obtained by the decomposition of Ca(OH)2, prepared by precipitating calcium nitrate with sodium hydroxide in ethylene glycol solution, exhibits the highest amount of very strong basic sites and stronger strength of basic sites, and therefore it catalyses the epoxidation of styrene with the highest rate among the tested CaO samples. Under the selected reaction conditions, the selectivity of 97.5% to styrene oxide at a conversion in excess of 99% could be obtained. 展开更多
关键词 EPoxidATION STYRENE calcium oxide hydrogen peroxide surface basicity
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Role of barium nitrate on the sulfur fixation of calcium oxide 被引量:1
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作者 LIU Guo-guang ZHENG Li-qing LU Wen-ying 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第1期75-78,共4页
In this paper, the effect of Ba(NO 3) 2 on the efficiency of sulfur fixation of calcium oxide during coal combustion was studied. The results showed that addition of barium nitrate to the CaO can enhance the sulfur ... In this paper, the effect of Ba(NO 3) 2 on the efficiency of sulfur fixation of calcium oxide during coal combustion was studied. The results showed that addition of barium nitrate to the CaO can enhance the sulfur removal rate of CaO significantly. The X \|ray diffraction spectrum of residual ash of coal added some sulfur fixative expressed that Ba\+\{2+\} can form a compound of Ba\|Al\|Si\|O which encloses the CaSO\-4 to prevent it's decomposition, so Ba\+\{2+\} can improve the action of sulfur fixation of CaO. The combustion character of the original coal and original coal added sulfur fixative was researched with thermal\|gravity analyzer and the results expressed that adding some sulfur fixative to the coal will make the combustion character of coal change little. 展开更多
关键词 coal combustion sulfur fixation calcium oxide barium nitr?
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Production of Bio-Calcium Oxide Derived from Hatchery Eggshell Waste Using an Industrial-Scale Car Bottom Furnace 被引量:1
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作者 Ajchara Imkum Putkham Suwanan Chuakham +2 位作者 Yuwadee Chaiyachet Tanapon Suwansopa Apipong Putkham 《Journal of Renewable Materials》 SCIE EI 2022年第4期1137-1151,共15页
The valorization of eggshell waste as bio-calcium oxide is crucial for pollution prevention and supporting sustainable development.There are several reports on the thermal conversion of eggshell waste to calcium oxide... The valorization of eggshell waste as bio-calcium oxide is crucial for pollution prevention and supporting sustainable development.There are several reports on the thermal conversion of eggshell waste to calcium oxide for the partial or complete substitution of natural lime applications.However,this paper reports the thermal decomposition of large amounts of hatchery eggshell waste on an industrial-scale car bottom furnace for the first time.The hatchery eggshell waste was sundried and placed into five stacked trays in the car bottom furnace.The calcination of the eggshell waste was conducted at 900℃ for 3 and 4 h under an atmosphere of air.Both the physical and chemical properties of the eggshell samples and the bio-quicklime products were carefully examined by TGA,SEM,XRD,FTIR,and XRF.The results demonstrate that the purity of calcium oxide in the quicklime products increased from 79%to 87%upon increasing the calcination time from 3 to 4 h.However,the color of the calcined eggshell samples at the surface of the pile was white while the color of the product beneath the surface was black or dark gray.The purity of the calcium oxide of both the black and white calcined samples was 76.4%and 91.5%,respectively.These results indicate the limited efficacy of the car bottom furnace for thermal decomposition of the large amount of eggshell waste to calcium oxide.Additionally,the production cost of bio-calcium oxide is approximately twice the cost of industrial grade lime.For further industrial applications,the furnace should contain the mixing equipment for improving the thermal decomposition of the large pile of eggshell waste.Furthermore,the oil burner system may be used in order to reduce fuel costs. 展开更多
关键词 EGGSHELL calcium oxide waste management thermal decomposition catalyst QUICKLIME
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Enhancing hydrogen evolution and oxidation kinetics through oxygen insertion into nickel lattice
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作者 Wanli Liang Xiyu Gong +9 位作者 Jinchang Xu Zixuan Dan Fanyan Xie Hulei Yu Hao-Fan Wang Yanshuo Jin Hongjuan Wang Yonghai Cao Hui Meng Hao Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期529-539,I0012,共12页
Nickel-based materials,including metallic Ni and Ni oxide,have been widely studied in the exploration of non-precious-metal hydrogen electrocatalysts,but neither pure Ni nor NiO is ideal for the hydrogen evolution rea... Nickel-based materials,including metallic Ni and Ni oxide,have been widely studied in the exploration of non-precious-metal hydrogen electrocatalysts,but neither pure Ni nor NiO is ideal for the hydrogen evolution reaction(HER)and hydrogen oxidation reaction(HOR).In this paper,an oxygen insertion strategy was applied on nickel to regulate its hydrogen electrocatalytic performance,and the oxygen-inserted nickel catalyst was successfully obtained with the assistance of tungsten dioxide support(denoted as O-Ni/WO_(2)).The partial insertion of oxygen in Ni maintains the face-centered cubic arrangement of Ni atoms,simultaneously expanding the lattice and increasing the lattice spacing.Consequently,the adsorption strength of^(*)H and^(*)OH on Ni is optimized,thus resulting in superior electrocatalytic performance of0-Ni/WO_(2)in alkaline HER/HOR.The Tafel slope of O-Ni/WO_(2)@NF for HER is 56 mV dec^(-1),and the kinetic current density of O-Ni/WO_(2)for HOR reaches 4.85 mA cm^(-2),which is ahead of most currently reported catalysts.Our proposed strategy of inserting an appropriate amount of anions into the metal lattice could provide more possibilities for the design of high-performance catalysts. 展开更多
关键词 Hydrogen evolution Hydrogen oxidation NICKEL Oxygen insertion Adsorption free energy
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Optimization of Lab-Scale Preparation of Biodiesel from Rubber Seed Oil Using Modified Calcium Oxide as Catalyst 被引量:1
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作者 Uma Krishnakumar V. Sivasubramanian 《Journal of Sustainable Bioenergy Systems》 2016年第3期55-65,共12页
Statistical analysis of product yield for biodiesel preparation by transesterification process was performed using the Minitab software. A standard RSM Design tool known as CCD was applied to study the transesterifica... Statistical analysis of product yield for biodiesel preparation by transesterification process was performed using the Minitab software. A standard RSM Design tool known as CCD was applied to study the transesterification reaction variables. The obtained parameters were verified experimentally for the transesterification reaction of rubber seed oil using solid metal oxide catalyst. The factors affecting the methyl ester yield during transesterification reaction were identified as the catalyst content, molar ratio of oil to alcohol and reaction time. High methyl ester yield and fast reaction rate could be obtained even if reaction temperature was relatively low, which is quite favorable to the industrial production of biodiesel from the rubber seed oil. 98.54% of methyl ester was formed from the transesterification of RSO with methanol. R-squared is a statistical measure of how close the data are to the fitted regression line. It is also known as the coefficient of determination, or the coefficient of multiple determination for multiple regression. In this study, an R<sup>2</sup> value of 0.98 is obtained. 展开更多
关键词 BIODIESEL Rubber Seed Oil TRANSESTERIFICATION calcium oxide
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Fermentation Characteristics of Silage of Sugar Cane Treated with Calcium Oxide,Lactobacillus buchneri and Their Associations 被引量:1
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作者 Fábio Tde Pádua Carlos A.A.Fontes +4 位作者 Joao C.C.Almeida Bruno B.Deminicis Lanamar de Almeida Carlos Otavio C.Neto Vitor Cde Oliveira 《American Journal of Plant Sciences》 2014年第5期636-646,共11页
We evaluated the fermentation products, the gaseous and effluent losses of sugarcane silages without calcium oxide (CaO) or with CaO addition, at the levels of zero, 0.8%, 1.6% and 2.4%, in association with the microb... We evaluated the fermentation products, the gaseous and effluent losses of sugarcane silages without calcium oxide (CaO) or with CaO addition, at the levels of zero, 0.8%, 1.6% and 2.4%, in association with the microbial additive Lactobacillus buchneri inoculated at the levels of zero, 50.000, 100.000 e 150.000 ufc/g of sugarcane, wet bases. The variety RB855536, harvested after 12 months of first growth was used. The experiment design was the completely randomized design, in a 4 × 4 factorial arrangement. They were evaluated in the silages, the contents of volatile fatty acids, lactic acid, ethanol, and the pH, as well as the gaseous and effluent losses. In the analysis of the data, the SAS system was utilized. It was observed on interaction effect of the chemical and microbial additive over the contents of lactic acid, acetic acid, propionic acid, butyric acid, ethanol and over the gaseous and effluents losses. However, there was no interaction effect regarding to pH. When it was observed on interaction effect of additives, the effects of the levels of one additive were evaluated by regression analysis in each level of each other, and vice-versa. The level 1.6% of CaO associated to the level 50,000 ufc/g of natural matter of Lactobacillus buchneri provided adequate levels of lactic acid (superior to 4.5%), and of acetic acid (around 1%), moderate content of propionic acid (0.55%), low content of butyric acid (0.05%) and controlled the production of ethanol and the gaseous and effluent losses. The pH of the silages were influenced by CaO addition, but were not affected consistently by microbial inoculation. 展开更多
关键词 Sugarcane Silage calcium oxide Lactobacillus buchneri Organic Acid
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High Temperature Interactions of Chrome Oxide Free Refractories with Coal Slag Under Simulated Gasification Conditions
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作者 ZHAO Shixian LI Hongxia +3 位作者 SUN Honggang CAI Binli WANG Lan KANG Yina 《China's Refractories》 CAS 2020年第2期1-5,共5页
Chrome oxide free refractories have significant economic benefits for the development of gasification technology.Spinel based and SiC based refractories are corroded by coal slag at 1500℃under reducing atmosphere.Mor... Chrome oxide free refractories have significant economic benefits for the development of gasification technology.Spinel based and SiC based refractories are corroded by coal slag at 1500℃under reducing atmosphere.Moreover,interactions between refractory materials and molten slag are also predicted by thermodynamic calculations under the same conditions.The results indicate that spinel based refractories are corroded by dissolution of molten slag,while SiC based refractories are corroded by oxidation of CO and FeO.Both of the spinel and SiC based refractories show good corrosion resistance against coal slag by the present experimental tests.Finally,preliminary developed spinel-SiC composite materials are prepared and corroded by coal slag as well,the research of which shows great potential to be used in slagging gasifiers. 展开更多
关键词 chrome oxide free refractories corrosion GASIFICATION thermodynamic calculation
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Free-Radical Conjugated Oxidation of Natural Methane by Hydrogen Peroxide
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作者 Latifa. M. Gasanova Zemfira. Yu. Ramazanova Tofik. M. Nagiev 《Journal of Chemistry and Chemical Engineering》 2011年第2期159-164,共6页
There has been carried out the process of noncatalytic oxidation of natural methane in the presence of hydrogen peroxide at the temperatures 840-880 ℃ what permitted to obtain hydrogen with high yield of hydrogen (... There has been carried out the process of noncatalytic oxidation of natural methane in the presence of hydrogen peroxide at the temperatures 840-880 ℃ what permitted to obtain hydrogen with high yield of hydrogen (74%) with inconsiderable quantity of CO (0.4%) in converted gas. As observed in the experiment, a variation of H2O2 concentration in the aqueous solution and other basic parameters of the process may induce the synthesis of gas with given H2:CO ratio for its further application in methanol or ammonia synthesis. In the latter process low CO concentration is required. Compared with the common high-temperature conversion of natural gas and further carbon oxide conversion on a catalyst, the current process promotes process simplification: the reaction is implemented at relatively low temperature (860-900 ℃ instead of 1400-1600 ℃for existing non-catalytic processes of methane conversion) and an additional unit for catalytic conversion of carbon oxide is excluded (in NH3 production). The mechanism of chemical conjugation in the CH4-H2O2-H2O system was elucidated and the inducing effect of H2O2 decomposition on the desired (secondary) reaction was quantitavely estimated. An adequate kinetic model was formulated on the basis of the proposed free-radical scheme. 展开更多
关键词 Conjugated oxidation hydrogen peroxide free radicals decomposition mechanism KINETIC
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Chemical Analysis of Magnesia and Magnesia-Alumina Refractory Materials——Flame atomic absorption spectrometric method for determination of calcium oxide content
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作者 ZHANG Xiaohui 《China's Refractories》 CAS 2006年第4期41-43,共3页
1 Scope This standard specifics the determination of calcium oxide coutent by flame atomic absorption spectrometric method.
关键词 Chemical Analysis of Magnesia and Magnesia-Alumina Refractory Materials Flame atomic absorption spectrometric method for determination of calcium oxide content
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Unsaturated transport properties of water molecules and ions in graphene oxide/hydrated calcium silicate nanochannels:from basic principles to complex environmental performance effects
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作者 Zhuye HUANG Yong FENG +1 位作者 Hongwei WANG Lei FAN 《Research and Application of Materials Science》 2022年第1期1-14,共14页
The problems of traditional concrete such as brittleness,poor toughness and short service life of concrete engineering under acid rain or marine environment need to be solved urgently.Hydrated calcium silicate(C-S-H)i... The problems of traditional concrete such as brittleness,poor toughness and short service life of concrete engineering under acid rain or marine environment need to be solved urgently.Hydrated calcium silicate(C-S-H)is a key component to improve the mechanical properties and durability of concrete.However,the traditional method of concrete material design based on empirical models or comparative tests has become a bottleneck restricting the sustainable development of concrete.The synthesis method,molecular structure and properties of C-S-H were systematically described in this paper;The interface structure and interaction of graphene oxide/calcium silicate hydrate(C-S-H/GO)were discussed.On this basis,the saturated and unsaturated transport characteristics of ions and water molecules in C-S-H/GO nanochannels under the environment of ocean and acid rain were introduced.The contents of this review provide the basis for improving the multi-scale transmission theory and microstructure design of concrete.It has important guiding significance for analyzing and improving the service life of concrete in complex environment. 展开更多
关键词 acid rain environment marine environment Service life of concrete Graphene oxide/calcium silicate hydrate molecular dynamics Unsaturated transport of ions and water molecules
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EFFECTS OF ω-ACRYLOYL POLY (ETHYLENE OXIDE) MACROMONOMER ON EMULSIFIER-FREE EMULSI0N COPOLYMERIZATION OF METHYL METHACRYLATE AND n-BUTYL ACRYLATE
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作者 郭天瑛 宋谋道 +2 位作者 周庆业 郝广杰 张邦华 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1998年第4期351-355,共5页
Well-defined nonionic hydrophilic ω-acryloyl poly(ethylene oxide) macro-monomer (PEO-A) has been prepared by living anionic polymerization of ethylene oxidewith diphenyl methyl potassium as the initiator and acryloyl... Well-defined nonionic hydrophilic ω-acryloyl poly(ethylene oxide) macro-monomer (PEO-A) has been prepared by living anionic polymerization of ethylene oxidewith diphenyl methyl potassium as the initiator and acryloyl chloride as the reaction termi-nating agent. The polymer was characterized by FTIR and SEC. The emulsifier-free emul-sion polymerization of methyl methacrylate (MMA) and n-butyl acrylate (BA) containingvarious concentrations of PEO-A was studied. In all cases stable emulsion coplymerizationsof MMA and BA were obtained. The stabilizing effect was found to be dependent on themolecular weight and the feed amount of the macromonomer. 展开更多
关键词 MACROMONOMER ω-Acryloyl poly(ethylene oxide) Emulsifier-free emulsion copolymerization Methyl methacrylate-n-butyl acrylate copolymer
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Removal of magnesium and calcium from electric furnace titanium slag by H_3PO_4 oxidation roasting-leaching process 被引量:4
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作者 郑富强 郭宇峰 +4 位作者 刘水石 邱冠周 陈凤 姜涛 王帅 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第2期356-366,共11页
H3PO4 oxidation roasting followed by HCl acid leaching was proposed to remove magnesium and calcium from electric furnace titanium slag containing 3.12% MgO and 0.86% CaO. XRF, XRD and SEM techniques were used to char... H3PO4 oxidation roasting followed by HCl acid leaching was proposed to remove magnesium and calcium from electric furnace titanium slag containing 3.12% MgO and 0.86% CaO. XRF, XRD and SEM techniques were used to characterize the composition, mineral phase component and microstructure of the titanium slag. The H3PO4 oxidation thermodynamic, mineral phase transformation, microstructure, element distribution in titanium slag during H3PO4 oxidation process and leaching process were investigated. The thermodynamic analysis indicated that H3PO4 could promote the decomposition of MgTi2O5 and CaSiO3. The results indicated that H3PO4 could effectively promote the transformation of titanium-bearing mineral to rutile and enrich the impurities in MxTi(3-x)O5 into phosphate which could be removed by acid leaching process. Under the studied conditions, the leaching rates of magnesium and calcium reached 94.68% and 87.19%, respectively. The acid leached slag containing 0.19% MgO and 0.13% CaO(mass fraction) was obtained. 展开更多
关键词 titanium slag oxidation roasting LEACHING H3PO4 MAGNESIUM calcium RUTILE
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Manganese extraction by reduction-acid leaching from low-grade manganese oxide ores using CaS as reductant 被引量:2
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作者 李昌新 钟宏 +3 位作者 王帅 薛建荣 武芳芳 张振宇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1677-1684,共8页
The extraction of manganese from low-grade manganese oxide ores using Ca S derived from Ca SO4 as reductant was investigated. The effects of mass ratio of Ca S to ore, reduction temperature, reduction time, liquid to ... The extraction of manganese from low-grade manganese oxide ores using Ca S derived from Ca SO4 as reductant was investigated. The effects of mass ratio of Ca S to ore, reduction temperature, reduction time, liquid to solid ratio(L/S ratio), stirring speed, leaching temperature, leaching time and H2SO4 concentration on the leaching rates of Mn and Fe during the reduction–acid leaching process were discussed. The leaching rates of 96.47% for Mn and 19.24% for Fe were obtained under the optimized conditions of mass ratio of Ca S to manganese oxide ore 1:6.7, L/S ratio 5:1, stirring speed 300 r/min, reduction temperature of 95 °C for 2.0 h in the reduction process and leaching stirring speed of 200 r/min, H2SO4 concentration of 1.5 mol/L, leaching temperature of 80 °C for 5 min in the leaching process. In addition, this process can be employed in the recovery of manganese from various manganese oxide ores, and Mn leaching rate above 95% is obtained. 展开更多
关键词 MANGANESE manganese oxide ore calcium sulfide REDUCTION LEACHING
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Abnormal Reactions of Free Radicals and Oxidative Damages in the Bodies of Patients With Chronic Glomerulonephritis 被引量:23
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作者 ZHOUJUN-FU CHENJIA-XI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第3期233-244,共12页
Objective To study the abnormal reactions of a series of free radicals and the oxidative damages induced by free radical abnormal reactions in the bodies of patients with chronic glomerulonephritis. Methods Eighty ... Objective To study the abnormal reactions of a series of free radicals and the oxidative damages induced by free radical abnormal reactions in the bodies of patients with chronic glomerulonephritis. Methods Eighty chronic glomerulonephritis patients (CGNP) and eighty healthy adult volunteers (HAV) were enrolled in a random control study, in which concentrations of nitric oxide (NO) in plasma, lipoperoxides (LPO) in plasma and in erythrocytes, and vitamin C (VC), vitamin E (VE) and beta-carotene (?CAR) in plasma as well as activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in erythrocytes were determined with spectrophotometric assays. Results Compared with the average values of the above biochemical parameters in the HAV group, the average values of NO in plasma, and LPO in plasma and erythrocytes in the CGNP group were significantly increased (P = 0.0001), while those of VC, VE and -CAR in plasma as well as those of SOD, CAT and GPX in erythrocytes in the CGNP group were significantly decreased (P = 0.0001). Pearson product-moment correlation analysis showed that with increase of the concentration of blood creatinine as well as prolongation of the course of disease in the CGNP, the concentrations of NO in plasma, and LPO in plasma and erythrocytes in the CGNP increased gradually, while the concentrations of VC, VE and ?CAR in plasma as well as the activities of SOD, CAT and GPX in erythrocytes in the CGNP decreased gradually (P = 0.002454 0.000001). The relative risk ratio (RR) of the above biochemical parameters reflecting oxidative damages in the bodies of CGNP ranged from 6.061 to 72.429. The reliability coefficient (alpha) that the above biochemical parameters were used to reflect the oxidative damages of the CGNP was 0.8137, standardized item alpha = 0.9728, Hotelling抯 T-Squared = 1135680.191, F = 53274.6478, P = 0.000001. Conclusions The findings in this study show that in the bodies of CGNP a series of free radical chain reactions result in severe pathological aggravation and induce oxidative damages in their bodies. Therefore, suitable dose of antioxidants should be supplemented to them so as to alleviate oxidative damages in their bodies. 展开更多
关键词 Chronic glomerulonephritis free radicals oxidation LIPOPERoxidATION Nitric oxide Lipoperoxides ANTIoxidANT Antioxidase oxidative stress oxidative damage
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Oxidative Stress and Free Radical Damage in Patients With Acute Dipterex Poisoning 被引量:15
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作者 JUN-FuZHOU WENZHOU +2 位作者 SHU-MEIZHANG YAN-ERLUO HUAI-HONGCHEN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第2期223-233,共11页
Objective To investigate whether acute dipterex poisoning (ADP) may cause oxidative stress and free radical damage in the bodies of acute dipterex poisoning patients (ADPPs), and to explore the mechanisms by which ADP... Objective To investigate whether acute dipterex poisoning (ADP) may cause oxidative stress and free radical damage in the bodies of acute dipterex poisoning patients (ADPPs), and to explore the mechanisms by which ADP may cause oxidative stress and free radical damage. Methods Fifty ADPPs and fifty healthy adult volunteers (HAVs) whose ages, gender and others were matched with the ADPPs were enrolled in a randomized controlled study, in which concentrations of nitric oxide (NO), vitamin C (VC), vitamin E (VE) and P-carotene (P-CAR) in plasma as well as concentration of lipoperoxide (LPO), and activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and acetylcholinesterase (AChE) in erythrocytes were determined by spectrophotometric analytical methods. Results Compared with the average values of experimental parameters in the HAVs group, the average values of plasma NO and erythrocyte LPO in the ADPPs group were significantly increased (P<0.0001), while those of plasma VC, VE and P-CAR as well as erythrocyte SOD, CAT, GPX and AChE in the ADPPs group were significantly decreased (P<0.0001). Bivariate correlation analysis and partial correlation analysis suggested that when NO and LPO values were increased, and VC, VE, β-CAR, SOD, CAT and GPX values were decreased in the ADPPs, AChE value was decreased gradually in the ADPPs (P<0.001-0.0001). Reliability analysis of experimental parameters reflecting oxidative stress and free radical damage in the ADPPs showed that the reliability coefficient (8 items) alpha=0.6909, and the standardized item alpha=0.8574. Conclusion The findings in the present study suggest that ADP can cause oxidative stress and free radical damage, and inhibit markedly erythrocyte acetylcholinesterase activity in ADPPs. 展开更多
关键词 Dipterex Dipterex poisoning oxidative stress free radical damage free radicals oxidation LIPOPERoxidATION ACETYLCHOLINESTERASE
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