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Highly efficient solution-processed CZTSSe solar cells based on a convenient sodium-incorporated post-treatment method 被引量:9
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作者 Biwen Duan Linbao Guo +7 位作者 Qing Yu Jiangjian Shi Huijue Wu Yanhong Luo Dongmei Li Sixin Wu Zhi Zheng Qingbo Meng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第1期196-203,I0007,共9页
In CZTSSe solar cells,a simple sodium-incorporation post-treatment method toward solution-processed Cu2Zn Sn S4precursor films is presented in this work.An ultrathin NaCl film is deposited on Cu2Zn Sn S4precursor film... In CZTSSe solar cells,a simple sodium-incorporation post-treatment method toward solution-processed Cu2Zn Sn S4precursor films is presented in this work.An ultrathin NaCl film is deposited on Cu2Zn Sn S4precursor films by spin-coating NaCl solution.In subsequent selenization process,the introduction of Na Cl is found to be benefacial for the formation of Cu2-xSe,which can further facilitate the element transportation,leading to dense and smooth CZTSSe films with large grains and less impurity Cu2Sn(S,Se)3phase.SIMS depth profiles confirm the gradient distribution of the sodium element in Na-doped absorbers.Photoluminescence spectra show that the introduction of appropriate sodium into the absorber can inhibit the band tail states.As high as 11.18% of power conversion efficiency(PCE)is achieved for the device treated with 5 mg mL^-1 NaCl solution,and an average efficiency of Na-doped devices is 10.71%,13%higher than that of the control groups(9.45%).Besides,the depletion width and the charge recombination lifetime can also have regular variation with sodium treatment.This work offers an easy modification method for high-quality Na-doped CZTSSe films and high-performance devices,in the meantime,it can also help to further understand the effects of sodium in CZTSSe solar cells. 展开更多
关键词 Thin film solar cell CZTSSe sodium doping POST-TREATMENT Spin-coating method
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A DFT Study on the Reaction Mechanism Involved in the Synthesis of Sodium Azide via Hydrazine Hydrate Method
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作者 孙华云 李明晶 刘永军 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第7期1045-1051,共7页
Sodium azide is a widely used inorganic compound. Besides the commonly used method of "Wislicenus process" which uses ammonia, nitrous and sodium as materials, the hydrazine hydrate route is also employed for the pr... Sodium azide is a widely used inorganic compound. Besides the commonly used method of "Wislicenus process" which uses ammonia, nitrous and sodium as materials, the hydrazine hydrate route is also employed for the preparation of sodium azide particularly in laboratory. However, because many species are involved in the reaction system, the reaction details for the hydrazine hydrate route are still unclear. A comprehensive understanding of the reaction mechanism may provide meaningful help for optimizing the production process. In this work, the reaction mechanism for the synthesis of sodium azide by hydrazine hydrate route has been studied using density function theory(DFT) method. On the basis of our calculations, the reaction details, including the energetics of ten elementary steps, the structures of intermediates and transition states as well as the influence of inorganic acids and alcohols, were illuminated at the atomistic level. Both the two steps, the generation of key intermediate(NH2-NH-NO) and the trans-cistransformation of NH2-NH-NO, are suggested to be the possible rate-limiting step, corresponding to the energy barriers of 20.3 and 22.7 kcal/mol, respectively. In the early reaction steps to generate NH2-NH-NO, the main role of sulphuric acid is to donate proton, which can be replaced by nitric acid or hydrochloric acid. From the energy point of view, isopropanol has similar reactivity as methanol and ethanol. 展开更多
关键词 sodium azide HYDRAZINE hydrate DFT method ISOPROPANOL sulphuric acid
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Fabrication of the Sodium Ions Extended Gate Field Effect Transistor by Using the Entrapment Method
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作者 Jung-Chuan Chou 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期246-247,共2页
The sodium ion is necessary in physiological function and an important element in blood of human body,because the concentration of the sodium ion in the blood directly affects the functions of some organs or pathologi... The sodium ion is necessary in physiological function and an important element in blood of human body,because the concentration of the sodium ion in the blood directly affects the functions of some organs or pathological feature,how to detect it is an important affair.In this paper,we measure the concentration of sodium ions by the extended gate field effect transistor (EGFET).We use three different substrates RuO_x/p-Si,ITO glass,SnO_2/ITO to fabricate EGFET,and we choose the optimum structure.The fabrication of device needed to use the entrapment method. 展开更多
关键词 sodium ion extended gate field effect transistor(EGFET) entrapment method
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STUDY ON MEAN ACTIVITY C0EFFICIENT OF 5,10,15,20—TETRAKIS PORPHYRIN SODIUM BY FREEZING—POINT DEPRESSION METHOD
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作者 徐英 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1997年第3期48-50,共3页
The mean activity coefficient of 5, 10,15 , 20-tetrakis (P-methoxyl-O-sulfophenyl)porphyrin sodium in dilute aqueous solution has been determined in the modality range 0. 00547-0. 08871 mol · kg-1at 273. 2 K by t... The mean activity coefficient of 5, 10,15 , 20-tetrakis (P-methoxyl-O-sulfophenyl)porphyrin sodium in dilute aqueous solution has been determined in the modality range 0. 00547-0. 08871 mol · kg-1at 273. 2 K by the freezing-point depression method . The results of γ± are 0. 9945-0. 7695, it is in close agreement with that by isopiestic method. 展开更多
关键词 5 10 15 20-tetrakis (p-methoxyl-o-sul-fophenyl) porphyrin sodium mean activity coefficient freezing-point depression method
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Wet reclamation of sodium silicate used sand and biological treatment of its wastewater by Nitzschia palea 被引量:5
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作者 Wang Huafang Fan Zitian +2 位作者 Yu Shaoqiang Liu Fuchu Li Xuejie 《China Foundry》 SCIE CAS 2012年第1期34-38,共5页
The massive amount of sodium silicate in the used sand was a pollution source, especially in the waste water from the wet reclamation of used sand. A new process of wet reclamation by biologically treating the waste w... The massive amount of sodium silicate in the used sand was a pollution source, especially in the waste water from the wet reclamation of used sand. A new process of wet reclamation by biologically treating the waste water produced during the wet reclamation process of used sand was studied in the paper. In the work, the precultivation of N. palea was performed firstly, and three different scrubbing solutions: (1) tap water, (2) modified medium for N. palea, and (3) filtrate of the broth treated by N. palea for 15 days, were used. The results of the primary investigation show that a de-skinning ratio of 90% is obtained when using the scrubbing solution containing modified medium for N. palea at the ratio 1:2 of sand and scrubbing solution, and the maximal concentrations of Na^+ and SiO3^2- are 1.49 g.L-1 and 0.51 g.L-1, respectively. The results of the optimal biomass, pH value decrease and Na^+ and SiO32 consumption indicate the optimal incubation conditions are at the irradiance of 5,000 lux and 25 ℃. Using the filtrate of the broth treated by N. palea for 15 days as the scrubbing solution directly, a de-skinning ratio of 93% is the highest compared to the results of the tap water and the modified medium for N. palea. In the biological process using N. palea, less water is used and little wastewater is produced, which is advantageous to the purpose of green manufacturing and environmental protection. 展开更多
关键词 sodium silicate used sand biological reclamation method N.palea
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Preparation of natural brucite nanofibers by the dispersion method 被引量:2
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作者 Li Xu Wen Ni +3 位作者 Wenping Li Xingde Liu Hailong Yang Xiaoguang Yang 《Journal of University of Science and Technology Beijing》 CSCD 2008年第4期489-494,共6页
The preparation of natural brucite nanofibers through dispersion by the wet process is described. The test results indicate that brucite fibers can be well dispersed by using sodium dioctyl sulfosuccinate (OT) as th... The preparation of natural brucite nanofibers through dispersion by the wet process is described. The test results indicate that brucite fibers can be well dispersed by using sodium dioctyl sulfosuccinate (OT) as the dispersant at a dispersant/fiber mass ratio of 0.15:1, dispersing for 30 min at a water/solid mass ratio of 20:1. The prepared nanofibers were characterized with X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM). It is shown that the prepared single brucite nanofiber is around 30 nm in diameter and the talus of the nonsingle brucite nanofibers is about 50-150 nm in diameter. Natural brucite mineral fibers were treated by the dispersion method to obtain nanomaterials. These fibers have significant advantages over artificial nanofibers both in yield and in cost. 展开更多
关键词 BRUCITE NANOFIBER sodium dioctyl sulfosuccinate (OT) ULTRASONIC dispersion method
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Microencapsulation of Sodium Hydrogen Carbonate to Generate Carbon Dioxide with Thermal Responsible Shell Material
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作者 Yohei Koyama Natsukaze Saito +2 位作者 Kiyomi Fuchigami Yoshinari Taguchi Masato Tanaka 《Journal of Cosmetics, Dermatological Sciences and Applications》 2015年第1期36-44,共9页
This paper tried to develop the optimum procedure for microencapsulating water soluble solid powder with the thermal responsible material by the melting dispersion cooling method. Sodium hydrogen carbonate was adopted... This paper tried to develop the optimum procedure for microencapsulating water soluble solid powder with the thermal responsible material by the melting dispersion cooling method. Sodium hydrogen carbonate was adopted as a water soluble solid powder instead of microencapsulating carbon dioxide gas. The shell material was composed of olefin wax and α-tocopherol. In the experiment, the concentration of oil soluble surfactant and the water soluble surfactant species were changed. Sodium hydrogen carbonate was treated in the aqueous solution dissolving the water soluble surfactant to form the finer sodium hydrogen carbonate powder and to increase the content. The microencapsulation efficiency could be increased with the concentration of oil soluble surfactant and considerably increased by treating sodium hydrogen carbonate with the water soluble surfactant. Sodium hydrogen carbonate was protected well from environmental water. The microcapsules showed the thermal responsibility to generate carbon dioxide. 展开更多
关键词 THERMAL Responsible Microcapsules Melting Dispersion Cooling method sodium HYDROGEN CARBONATE Olefin Wax Α-TOCOPHEROL
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Development, Validation and Application of a Spectrofluorimetric Method for the Quantification of Nevirapine in Pharmaceutical Formulations Tablets and Suspensions
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作者 Lucien Murhula Namegabe Aladin Ombeni Mahano Serigne Omar Sarr 《American Journal of Analytical Chemistry》 2022年第6期206-227,共22页
The development of the spectrofluorimetric method can be considered a promising alternative that is relatively less expensive and sufficiently reliable. In the current literature, no method for the analysis of nevirap... The development of the spectrofluorimetric method can be considered a promising alternative that is relatively less expensive and sufficiently reliable. In the current literature, no method for the analysis of nevirapine by spectro-fluorimetric has been reported. The proposed method is based on the transformation of naturally non-fluorescent nevirapine into a fluorescent derivative after chemical synthesis. Maximum excitation and emission wavelengths are 290 nm and 357 nm respectively. The analytical performance of the method demonstrates linearity in the concentration range 1.5 × 10<sup>-2</sup> and 13.5 × 10<sup>-2</sup> μg/mL with a correlation coefficient (r) greater than 0.999. The detection (LOD) and quantification (LOQ) limits found are 1.97 × 10<sup>-3</sup> μg/mL and 5.48 × 10<sup>-3</sup> μg/mL respectively. Recovery is achieved with 99.9% and 100.3% trueness, intra-day precision with a coefficient of variation of repeatability (CVr) of 0.99% and inter-day precision with a coefficient of variation of precision (CVR) of 1.7%. The method has been successfully applied in the analysis of 10 batches of nevirapine tablets and suspensions. 展开更多
关键词 Spectrofluorimetric method Validation Nevirapine sodium Hypochlorite
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高含泥人工砂不同清洗方式对混凝土性能影响研究
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作者 吕兴栋 和超 +3 位作者 夏求林 李平刚 周世华 刘恒 《水利水电技术(中英文)》 北大核心 2024年第S01期434-439,共6页
依托于滇中引水工程,研究了清水清洗和六偏磷酸钠清洗高含泥人工砂对MB值和混凝土性能的影响,对比了不同方式的技术经济性。结果表明:与清水清洗相比,采用六偏磷酸钠溶液清洗,MB值下降更明显,同时可避免石粉大量流失,混凝土的力学性能... 依托于滇中引水工程,研究了清水清洗和六偏磷酸钠清洗高含泥人工砂对MB值和混凝土性能的影响,对比了不同方式的技术经济性。结果表明:与清水清洗相比,采用六偏磷酸钠溶液清洗,MB值下降更明显,同时可避免石粉大量流失,混凝土的力学性能和变形性能更佳。具体而言,采用清水清洗人工砂,MB值从1.4 g/kg下降至0.85 g/kg,石粉含量从21.8%降低至10.3%。采用六偏磷酸钠溶液清洗人工砂,MB值从1.4 g/kg下降至0.45 g/kg,石粉含量从21.8%降低至16.8%;保持混凝土拌和物状态相同的条件下,采用六偏磷酸钠溶液清洗人工砂,混凝土用水量下降了40 kg/m^(3),28 d龄期混凝土抗压强度、劈拉强度和极限拉伸值分别提高11.7%、23.1%和24.1%,60 d龄期混凝土干缩率降低106×10^(-6),混凝土原材料成本降低了23.3元/m^(3)。 展开更多
关键词 含泥量 MB值 清洗方式 六偏磷酸钠 混凝土性能
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Preparation of Thermosensitive Microcapsules Containing Water Soluble Powder by Melting Dispersion Cooling Method 被引量:1
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作者 Yoshinari Taguchi Natsukaze Saito +1 位作者 Atsunori Uchida Masato Tanaka 《Journal of Encapsulation and Adsorption Sciences》 2016年第3期57-69,共14页
It was tried to prepare the thermosensitive microcapsules containing the water soluble solid powder by the melting dispersion cooling method and to establish the optimum preparation conditions. As a model water solubl... It was tried to prepare the thermosensitive microcapsules containing the water soluble solid powder by the melting dispersion cooling method and to establish the optimum preparation conditions. As a model water soluble solid powder, sodium hydrogen carbonate was adopted in order to generate carbon dioxide gas and as a thermosensitive shell material, olefin resin with the melting point of ca. 40°C was used. In the experiment, the concentration of olefin resin in the shell material solution was mainly changed together with the concentrations of the oil soluble surfactant species and the α-tocopherol as a modifier of shell. Addition of α-tocopherol into the shell material solution could prevent the core from breaking away during the microencapsulation process and result in the higher microencapsulation efficiency, because the dispersion stability of solid powder in the shell material solution could be increased due to the increase in affinity between the shell material solution and solid powder. Also, the microencapsulation efficiency increased with the concentration of olefin resin, became maximum at 50 wt% and then, decreased. The microcapsules were found to begin melting at 36°C and to generate carbon dioxide gas. 展开更多
关键词 Thermosensitive Microcapsules MICROENCAPSULATION sodium Hydrogen Carbonate Melting Dispersion Cooling method Olefin Resin
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基于加权TOPSIS法的贝米肝素钠注射液药物利用评价
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作者 田璐璐 李美娟 +2 位作者 祝德秋 蔡慧雅 张进华 《药物流行病学杂志》 CAS 2024年第5期481-488,共8页
目的建立贝米肝素钠注射液药物利用评价(DUE)标准,并采用加权优劣解距离(TOPSIS)法对贝米肝素钠注射液的使用情况进行评价,为促进其合理使用提供参考。方法以药品说明书为基础,参考相关指南和文献,采用专家咨询法建立贝米肝素钠注射液的... 目的建立贝米肝素钠注射液药物利用评价(DUE)标准,并采用加权优劣解距离(TOPSIS)法对贝米肝素钠注射液的使用情况进行评价,为促进其合理使用提供参考。方法以药品说明书为基础,参考相关指南和文献,采用专家咨询法建立贝米肝素钠注射液的DUE标准细则,采用加权TOPSIS法对同济大学附属同济医院2021年6—7月使用贝米肝素钠注射液的住院患者病历进行合理性评价。结果在贝米肝素钠注射液DUE标准中,10个二级指标相对权重系数排名前2位的是禁忌证、不良反应处置,排名后2位的是给药方式、适应证。共纳入100份病历,用药方案与最优方案接近程度(C_(i))≥0.8(合理)的0例;0.6≤C_(i)<0.8(基本合理)的83例(83.00%);C_(i)<0.6(不合理)的17例(17.00%)。不合理用药主要表现在超适应证用药、超给药方式用药、存在潜在药物相互作用、给药剂量不适宜、违反用药禁忌证等方面。结论基于加权TOPSIS法的贝米肝素钠注射液DUE方法可综合多个评价指标,可操作性强,评价结果客观可信。该院贝米肝素钠注射液临床应用基本合理,需加快超说明书用药循证评价流程,加强管理力度,以保证临床合理用药。 展开更多
关键词 贝米肝素钠注射液 加权优劣解距离法 药物利用评价
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Heparin Sodium Was Prepared from Pig Intestinal Mucosa by Dialysis and Spray Drying
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作者 Shunshun Shu Qian Mi +3 位作者 Caixia Yang Chonghuan Bao Zhaoyang Wang Jun Niu 《Journal of Biosciences and Medicines》 2018年第10期5-11,共7页
A method to extract crude heparin sodium from pig intestinal mucosa by dialysis and spray drying was established. The pig intestinal mucosa was treated in the following steps: enzymolysis, resin exchange adsorption-wa... A method to extract crude heparin sodium from pig intestinal mucosa by dialysis and spray drying was established. The pig intestinal mucosa was treated in the following steps: enzymolysis, resin exchange adsorption-washing, elution, pressure filtration, dialysis, spray drying. Activity of the product was measured using a heparin anti-IIa factor assay kit. The yield of crude heparin obtained by this method was 2.79% higher than that of oven drying method;the production of 1 kg crude heparin sodium saved 43.4 pigs small intestine. The activity was 98.48 ± 2.49 IU/mg (n = 5), 15.18 IU/mg higher than that obtained by oven drying method. The product is pale white powder, attractive color and easy to dissolve. 展开更多
关键词 HEPARIN sodium DIALYSIS and Spray DRYING OVEN DRYING method The Production Process
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苦荞叶提取物清除亚硝酸钠及阻断亚硝胺合成作用研究
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作者 唐远谋 周玲 +1 位作者 张宝丹 尹俊杰 《中国食品添加剂》 CAS 2024年第6期123-131,共9页
采用超声波辅助,响应面优化苦荞叶清除亚硝酸钠物质提取工艺,并以Vc和甘草提取物为对照,探究苦荞叶提取物对亚硝胺合成的阻断作用。结果表明,苦荞叶清除亚硝酸钠物质提取最佳工艺条件为:乙醇浓度44%,超声功率260 W,料液比21 mL/g,目数... 采用超声波辅助,响应面优化苦荞叶清除亚硝酸钠物质提取工艺,并以Vc和甘草提取物为对照,探究苦荞叶提取物对亚硝胺合成的阻断作用。结果表明,苦荞叶清除亚硝酸钠物质提取最佳工艺条件为:乙醇浓度44%,超声功率260 W,料液比21 mL/g,目数为80目,超声时间为30 min,提取温度50℃,此条件下苦荞叶提取物对亚硝酸钠的清除率为(83.97±0.12)%;在20~100 mg/L溶度范围内,Vc、苦荞叶提取物和甘草提取物对亚硝胺合成的阻断率线性关系良好,其对应的半阻断浓度IC50分别为61.26、80.09和90.20 mg/L。质量浓度继续增加时,苦荞叶提取物和甘草提取物对亚硝胺合成的阻断率随之下降,但同浓度情况下苦荞叶提取物对亚硝胺合成的阻断率高于甘草提取物,苦荞叶提取物对亚硝胺合成的阻断作用弱于Vc,但强于甘草提取物。 展开更多
关键词 苦荞叶 响应曲面法 亚硝酸钠 亚硝胺
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Experimental and Quantum Chemical Studies of the Inhibition of Copper with Sodium Dodecyl Sulphate (SDS) in Acidic Medium
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作者 Mojisola O. Nkiko Abayomi Oluwabi +1 位作者 Sikiru A. Ahmed Janet T. Bamgbose 《Engineering(科研)》 2018年第12期851-862,共12页
This work investigates the inhibitive properties of sodium dodecyl sulphate (SDS) on the corrosion of copper (Cu) in nitric acid using gasometric methods. The inhibition efficiency increases with time and concentratio... This work investigates the inhibitive properties of sodium dodecyl sulphate (SDS) on the corrosion of copper (Cu) in nitric acid using gasometric methods. The inhibition efficiency increases with time and concentration of SDS. The corrosion rate of copper decreases as concentration of SDS increases. Adsorption of the SDS on the surface obeyed the Langmuir adsorption isotherm. The high negative values of the kinetic parameter B suggest that the inhibitor’s effectiveness increases with temperature. The equilibrium constant and the free energy of adsorption of SDS to copper are negative and large. This observation implies that the adsorption mechanism maybe chemisorption. The quantum chemical calculation of copper dodecyl sulphate shows that the energy change in the HOMO-LUMO energy of the moiety is positive and small. This observation implies that the SDS is an efficient inhibitor. The high dipole moment obtained implies that corrosion inhibition of Cu is enhanced by adsorption of SDS and this observation correlates with the observed experimental inhibition efficiency. 展开更多
关键词 Corrosion INHIBITION COPPER Gasometric methods ADSORPTION INHIBITION Efficiency sodium Dodecyl Sulphate (SDS)
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Preparation of Microcapsules Containing Artificial Diet for Tropical Fishes with Spray Gelling Method
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作者 Yoshinari Taguchi Takanori Suzuki +1 位作者 Natsukaze Saito Masato Tanaka 《Journal of Encapsulation and Adsorption Sciences》 2017年第1期1-9,共9页
The microcapsules containing the artificial diet for tropical fishes were prepared with the spray gelling method in order to prevent water environmental pollution. The carboxymethyl cellulose sodium aqueous solution, ... The microcapsules containing the artificial diet for tropical fishes were prepared with the spray gelling method in order to prevent water environmental pollution. The carboxymethyl cellulose sodium aqueous solution, in which α-tocopherol droplets containing the powdery artificial diet were dispersed, was dropped or sprayed into the chitosan aqueous solution. Microcapsules were prepared by forming polyionic complex shell made from chitosan and carboxymethyl cellulose sodium. In the experiment, the concentration of carboxymethyl cellulose sodium (CMCNa) was mainly changed to investigate the effect on the diameters of microcapsules, the content and the microencapsulation efficiency. The microcapsules couldn’t be prepared with the concentration of carboxymethyl cellulose sodium less than 3.0 wt%. The microcapsules were the core-shell type. The diameters of microcapsules were increased with the concentration of CMCNa and the microencapsulation efficiency of ca. 100% could be obtained by the preparation method presented in this study. The microcapsules were found to be eaten well by tropical fishes and to prevent water environmental pollution. 展开更多
关键词 Microencapsulated Diets SPRAY GELLING method HETEROCOAGULATION Artificial Diet CARBOXYMETHYL Cellulose sodium
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燃烧-微库仑法汽油中有机氯含量测定方法的优化
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作者 杨森 张元广 +1 位作者 陆克平 陈燕梅 《石化技术与应用》 CAS 2024年第2期144-148,共5页
为了提高汽油中有机氯含量测定的准确度和精密度,基于燃烧-微库仑法,采用0.02 mol/L乙酸钠的水溶液作汽油无机氯萃取剂,优化了直接测定和总氯含量差减无机氯含量(差减法)测定汽油中有机氯含量的方法。结果表明:采用0.02 mol/L乙酸钠的... 为了提高汽油中有机氯含量测定的准确度和精密度,基于燃烧-微库仑法,采用0.02 mol/L乙酸钠的水溶液作汽油无机氯萃取剂,优化了直接测定和总氯含量差减无机氯含量(差减法)测定汽油中有机氯含量的方法。结果表明:采用0.02 mol/L乙酸钠的水溶液取代水-乙醇(异丙醇)溶液作无机氯萃取剂,可取上层油相直接测定汽油有机氯含量;采用萃取剂内含0.10~0.20 mg/L无机氯盐的空白加标方法,解决现行差减法部分汽油中有机氯含量偏差大的问题;2种方法的测定结果相对偏差均不大于10%。 展开更多
关键词 汽油 无机氯 有机氯 燃烧-微库仑法 萃取剂 乙酸钠水溶液
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“No Need to Get Salty” Or Is There? Sodium Functionality as a Consideration in Nutrition Public Health Policy
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作者 Molly Riordan Brandy-Joe Milliron +3 位作者 Rachel Sherman Lauren Miller Jennifer Aquilante Jonathan Deutsch 《Food and Nutrition Sciences》 2021年第2期138-146,共9页
<b><span>Aim:</span></b><span> Public health professionals focus on both downstream (individual) and upstream (population-level) interventions to reduce sodium consumption and prevent sod... <b><span>Aim:</span></b><span> Public health professionals focus on both downstream (individual) and upstream (population-level) interventions to reduce sodium consumption and prevent sodium-related chronic diseases. Effective upstream interventions specifically aimed at reducing dietary sodium intake include the implementation of comprehensive nutrition standards that restrict the amount of sodium contain<span>ed in foods available for purchase. <span>The aim of this work was</span> to identify sought-after foods that did not meet the Philadelphia Nutrition Standards’ sodium limits and reformulate those foods to be standards-compliant</span> and consumer-acceptable. <b>Subject and Methods:</b> Two foods were reformulated for <span>compliancy</span> with the Philadelphia Nutrition Standards’ sodium limits and consumer acceptability: the hoagie roll and soft pretzel. Reformulation included sensory testing and engaging potential manufacturing partners to investigate products’ commercial potential. <b>Results: </b>While hoagie roll reformulation led to a local company manufacturing and selling the reformulated product, soft pr<span>etzel reformulation stalled due to lack of consumer acceptability of the reformulated product. Salt contributes desirable characteristics in the texture, taste, and appearance of the soft pretzel, the absence of which consumers found unacceptable. <b>Conclusion:</b> Product reformulation holds great potential to create lower-sodium foods that otherwise have all of the characteristics of the higher-sodium </span></span><span>“</span><span>original</span><span>”</span><span> products but requires an understanding of the role of salt in produ</span><span>ct recipes. Reducing salt without considering its multiple functions in food may result in a product that is unacceptable or even unsafe. A simple four-step tool can help public health practitioners evaluate the extent to which products are suitable for reformulation.</span> 展开更多
关键词 sodium Chloride Dietary/Administration & Dosage Health Promotion/methods Nutrition Policy Food/Standards Food Technology
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基于PRECEDE模式的居民减盐行为影响因素的混合方法研究 被引量:1
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作者 张幸 董静 +7 位作者 郭怡 徐建伟 白雅敏 刘敏 张晓畅 郭晓雷 马吉祥 孙昕霙 《中国全科医学》 北大核心 2024年第10期1221-1230,共10页
背景中国居民高血压患病率高而控制率低,大量流行病学研究表明减少膳食盐的摄入有助于降低血压水平,因此探索居民减盐行为的影响因素对于居民自身的健康管理及减轻社会负担意义重大。目的基于PRECEDE模式,探索山东居民减盐行为的倾向因... 背景中国居民高血压患病率高而控制率低,大量流行病学研究表明减少膳食盐的摄入有助于降低血压水平,因此探索居民减盐行为的影响因素对于居民自身的健康管理及减轻社会负担意义重大。目的基于PRECEDE模式,探索山东居民减盐行为的倾向因素、强化因素和促成因素,为后续减盐工作提供科学建议。方法运用混合研究方法,采用目的抽样法,先后于2016年和2018年采访居民共计114名,访谈提纲主要包含对控盐的态度、在控盐过程中遇到的困难以及获得的帮助等。定量数据来源于2016年山东省减盐防控高血压项目终末调查鲁东、鲁中南地区的问卷数据,从数据库中选取与高血压相关调查内容,共纳入研究样本6697份。结果多分类Logistic回归结果显示,在控制其他变量影响下,性别、职业、文化程度对减盐行为依从性有影响(P<0.05)。在控制个人一般情况的影响下,个人口味、减盐知识及对低盐饮食的态度对减盐行为依从性有影响(P<0.05)。医生的干预能强化居民减盐行为。通过医务人员的健康教育,不仅能增强高血压患者的减盐行为与意识,还能加强家人的督促,提升家人的减盐行为与意识,进而达到促进居民减盐的目的。家人在日常生活中的督促能强化居民控盐行为。山东省减盐行动制定了项目推进政策、餐饮业政策、食品业政策以及减盐健康教育政策,打造了浓厚的减盐大环境。低盐产品中对居民影响较大的是限盐勺,低盐食品及低钠盐的可及性相对较低影响了其控盐作用。大众媒体宣传是居民获得减盐信息的主要途径,目前作用较为明显的大众传播方式包括电视和在公共场所的宣传。结论对低盐饮食的态度及知识水平因素是影响居民减盐行为的倾向因素;医生的劝诫和家人的提醒能帮助居民开始减盐,也能强化居民减盐行为,属于强化因素;减盐相关政策、大众传播为居民减盐创造了社会氛围,减盐相关产品则提供了现实条件,属于促成因素。 展开更多
关键词 高血压 膳食 限钠 混合方法研究 PRECEDE模式 影响因素分析
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煤层H_(2)S与煤脱硫协同治理研究
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作者 高飞 张芸鸣 +2 位作者 杨玉龙 侯渊 申佳琦 《安全与环境学报》 CAS CSCD 北大核心 2024年第8期3116-3125,共10页
为研究煤层H_(2)S与煤脱硫的协同治理,自制装置对复配碱液进行H_(2)S吸收和煤脱硫试验。采用离子色谱法、X射线光电子能谱、形态硫测试对吸收液和煤样进行表征,分析协同治理机理,利用响应面法分析各因素对H_(2)S吸收和煤脱硫的影响程度... 为研究煤层H_(2)S与煤脱硫的协同治理,自制装置对复配碱液进行H_(2)S吸收和煤脱硫试验。采用离子色谱法、X射线光电子能谱、形态硫测试对吸收液和煤样进行表征,分析协同治理机理,利用响应面法分析各因素对H_(2)S吸收和煤脱硫的影响程度。结果显示:单一碱液均可吸收H_(2)S,但脱硫效果微弱;添加NaClO后,协同治理效果显著且能避免H_(2)S二次逸散,其中NaOH+NaClO协同治理效果最优。在反应后,H_(2)S及煤中低价态硫噻吩、硫醇和硫醚减少,吸收液中SO_(4)^(2-)及煤中高价态硫(亚)砜增加,表明NaOH为元素硫歧化提供碱性条件,元素硫继而被NaClO氧化。NaOH质量浓度对H_(2)S吸收影响最大,NaClO质量浓度对煤脱硫影响最大,NaOH和NaClO交互对煤脱硫与H_(2)S吸收影响显著。利用Design-Expert软件确定最佳参数:NaOH质量浓度为54 g/L、NaClO质量浓度为54 g/L、温度为21.4℃。 展开更多
关键词 安全工程 煤炭脱硫 硫化氢吸收 碱性次氯酸钠溶液 响应面方法 最佳参数选择
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气化渣酸浸液去除铁铬及聚合氯化铝制备
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作者 周季龙 王亚茹 +3 位作者 魏怡菲 孙建平 孙伟 岳彤 《中国有色金属学报》 EI CAS CSCD 北大核心 2024年第12期4111-4125,共15页
气化渣是煤气化工艺产生的固体废弃物,其大量排放严重威胁生态环境,制约煤化工行业发展。本文针对气化渣高钙、高铁、低铝、含铬的物相组成的特点,通过混酸逆流浸出过程实现液相中铝的富集和钙离子的去除,并有效降低了浸出液中的余酸量... 气化渣是煤气化工艺产生的固体废弃物,其大量排放严重威胁生态环境,制约煤化工行业发展。本文针对气化渣高钙、高铁、低铝、含铬的物相组成的特点,通过混酸逆流浸出过程实现液相中铝的富集和钙离子的去除,并有效降低了浸出液中的余酸量,然后针对浸出液中的铁、铬进行除杂,得到可制备合格聚合氯化铝(PAC)的净化液,并以该富铝净化液为原料,进一步考察氯化铝和氢氧化铝添加量对聚合氯化铝产品性能的影响。结果表明:混酸逆流浸出阶段的最佳条件为盐酸浓度2.125 mol/L、硫酸浓度0.69 mol/L、液固比4∶1、温度85℃、时间4 h。在此条件下,铝浸出率达85.39%。黄钠铁矾法除杂最佳条件为反应温度97℃、反应时间1.5 h、终点pH=2.0,在此条件下,除铁率和除铬率分别达到69.46%和51.36%。在制备PAC阶段,采用净化液为原料,加入150 g/L氯化铝和100 g/L氢氧化铝,经60℃水解1 h、85℃聚合1.5 h后,制得符合国家标准GB/T 22627—2022的液体PAC产品,其去浊率达94.33%。 展开更多
关键词 气化渣 逆流浸出 黄钠铁矾法 聚合氯化铝
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