不同活化制度对活性炭制备工艺的影响

以辣椒秸秆为原料、K_2CO_3为活化剂制备活性炭(AC),研究不同活化制度对AC制备工艺的影响。选取活化温度、活化时间、浸泡时间、K_2CO_3/炭化料比率和升温速率为影响因子,通过Plackett-Burman(P-B)设计筛选出主要因子,采用中心复合设计法(Central Composite Design,CCD)对其优化,得到样品比表面积和得率的预测模型,并验证和确定最佳制备工艺。利用扫描电子显微镜(SEM)和比表面积及孔径分析仪对样品的形貌和结构进行表征分析。结果表明:对AC比表面积和得率影响显著(P<0.05)的活化因子依次为:活化温度>活化时间>升温速率;最佳工艺条件为活化温度835℃,活化时间1.95 h,升温速率4.5℃/min。在此条件下AC比表面积、得率分别为1648.30 m^2/g、34.29%,与预测值(1728.48 m^2/g、34.68%)的误差分别为4.63%(<5%)、1.12%(<5%),为辣椒秸秆的资源化利用提供参考。

活化制度对镍氢电池高温性能的影响

研究了高温活化对SC型镍氢电池高温性能的影响,结果表明,高温活化可以提高SC型镍氢电池的高温性能。在(40±2)℃高温下进行镍氢电池活化,可有效地抑制或延迟氧气的析出,提高镍氢电池的充电能力。此外高温活化还可以延缓镍氢电池放电态搁置时的OCV下降速度,抑制高温自放电速率,有效的提高镍氢电池的高温荷电保持能力。该电池比市场上的SC型镍氢电池的高温性能好,高温充电能力提高15%,高温放电能力提高5%,高温荷电保持能力提高10%。

复合矿化剂作用下增钙煤矸石的活化效果研究

以江苏宜兴煤矸石为主要研究对象，掺入钙质材料后，在．自配复合矿化剂作用下高温煅烧成活化煤矸石，采用X射线衍射（XRD）和红外吸收光谱（IR）对其结构特征进行了分析，并对其胶凝性能进行了试验．结果表明：在复合矿化剂作用下，于1000～1100℃下煅烧而成的活化煤矸石中有cA生成，在低活化条件（1000℃，保温0．5，1．0h）下，有CS，Ca3Al生成，活化温度升高至1050℃并保温0．5h时，CaA1O，8消失，在此温度下延长保温时间至1．0h时，CS消失，ECa4（Al2O4）]。卜生成．各活化煤矸石的胶凝性能不同，其中以1050℃下保温0．5h煅烧而成的活化煤矸石对水泥净浆抗压强度影响最大，将其以30％（质量分数）替代水泥后，体系28d的净浆抗压强度可达70．16MPa．

掺加石灰石煅烧煤矸石及其在水泥水化过程中的作用机理

以江苏宜兴煤矸石为主要研究对象,对其基本物性进行分析可知,其成分以SiO2、Al2O3为主,CaO含量较低;矿物组成以高岭石和石英为主,属于低钙粘土类物质。在复合矿化剂作用下于1000～1100℃高温煅烧制成活化煤矸石样,分析各活化样的结构特征,并在检验其胶凝性能的基础上,运用化学结合水量、Ca(OH)2量测定等方法对活化煤矸石水泥的水化过程进行追踪测定。研究结果表明,各活化煤矸石的胶凝性能不同,其中以1050℃保温0.5h煅烧而成的活化样对水泥强度的影响最大,将其以30%掺量替代水泥后,体系28d净浆强度达到70.16MPa。水化过程的分析结果与宏观力学强度结果基本吻合。

Effects of coal rank, Fe_3O_4 amounts and activation temperature on the preparation and characteristics of magnetic activated carbon

Coal-based Magnetic Activated Carbons （CMAC＇s） were prepared from three representative coal samples of various ranks： Baorigele lignite from Inner Mongolia; Datong bitumite from Shanxi province; and Taixi anthracite from Ningxia Hui Auto- nomous Region. Fe3O4 was used as a magnetic additive. A nitrogen-adsorption analyzer was used to determine the specific surface area and pore structure of the resulting activated carbons. The adsorption capacity was assessed by the adsorption of iodine and methylene blue. X-ray diffraction was used to measure the evolution behavior of Fe304 during the preparation process. Magnetic properties were characterized with a vibrating-sample magnetometer. The effect of the activation temperature on the performance of CMAC＇s was also studied. The results show that, compared to Baorigele lignite and Taixi anthracite, the Datong bitumite is more appropriate for the preparation of CMAC＇s with a high specific surface area, an advanced pore structure and suitable magnetic properties. Fe304 can effectively enhance the magnetic properties and control the pore structure by increasing the ratio of meso- pores. An addition of 6.0% Fe304 and an activation temperature of 880 ℃ produced a CMAC having a specific surface area, an iodine adsorption, a methylene blue adsorption and a specific saturation magnetization of 1152.0 m2/g, 1216.7 mg/g, 229.5 mg/g and 4.623 emu/g, respectively. The coal used to prepare this specimen was Datong bitumite.

面向现代企业需求的法学职业教育改革

现代法学教育应以民商法的教学为重心，民商法学的教学应依现代企业对于法律人才的需求为目标．遵循制度生活化、知识体系化和理论实践化的原则，还原民法制度与生活的关联，强化法学知识的系统性和理论的实用性。

Effect of mechanical activation on alkali leaching of chromite ore

Mechanical activation was used to improve the extraction of chromium in molten NaOH.It is observed that the extraction ratio reaches 97% after leaching for 200 min when chromite ore is mechanically activated for 10 min,but only 34% if not activated.Mechanical activation can decrease the particle size,increase the surface area,and enhance the lattice distortion.Further,the mechanisms for mechanical activation were exposed.The results show that the mechanical activation mainly focuses on chromite ore particle size decrease and the lattice distortion.The formation of aggregation weakens the strengthening effect of mechanical activation for releasing high surface energy.

Effect of rolling processing on microstructure and electrochemical properties of high active aluminum alloy anode

The effect of rolling processing on the microstructure,electrochemical property and anti-corrosion property of Al-Mg-Sn-Bi-Ga-In alloy anode in alkaline solution(80℃,Na2SnO3+5 mol/L NaOH)was analyzed by the chronopotentiometry (E-T curves),hydrogen collection tests and modern microstructure analysis.The results show that when the rolling temperature is 370℃,the electrochemical activity of Al anode decreases gradually with the increase of pass deformation in rolling,while the anti-corrosion property is improved in the beginning and then declined rapidly.When the pass deformation of rolling is 40%,the Al anode has good electrochemical activity as good as the anti-corrosion property and with the increase of rolling temperature,both electrochemical activity and anti-corrosion property of Al anode increase first and then decrease.When the rolling temperature is 420 ℃,the aluminum alloy anode has the most negative electrode potential of about-1.521 V(vs Hg/HgO)and the lowest hydrogen evolution rate of 0.171 6 mL/(min·cm2).The optimum comprehensive performance of Al alloy anode is obtained.

Role of Ni(NO_3)_2 in the preparation of a magnetic coal-based activated carbon

The role of Nil（NO3）2 in the preparation of a magnetic activated carbon is reported in this paper. Magnetic coal-based activated carbons （MCAC） were prepared from Taixi anthracite with low ash content in the presence of Ni（NO3）2. The MCAC materials were characterized by a vibrating sample magnetometer （VSM）, X-ray diffraction （XRD）, a scanning electric microscope （SEM）, and by N2 adsorption. The cylindri- cal precursors and derived char were also subjected to thermogravimetric analysis to compare their behavior of weight losses during carbonization. The results show that MCAC has a larger surface area （1074 m21g） and a higher pore volume （0.5792 cm3/g） with enhanced mesopore ratio （by about 10~）. It also has a high saturation magnetization （1.6749 emu/g） and low coercivity （43.26 Oe）, which allows the material to be magnetically separated. The MCAC is easily magnetized because the nickel salt is con- vetted into Ni during carbonization and activation. Metallic Ni has a strong magnetism on account of electrostatic interaction. Added Ni（NO3）2 catalyzes the carbonization and activation process by accelerat- ing burn off of the carbon, which contributes to the development of mesopores and macropores in the activated carbon.

Reduction mechanism of Fe2O3-Cr2O3-NiO system by carbon

Isothermal experiments on the reduction of Fe_2O_3-Cr_2O_3-NiO(molar ratio of Fe-to-Cr-to-Ni is 3:2:2)by graphite were carried out at 1350–1550°C,and effects of various factors on reduction degree were studied.The results show that the reaction rate of the Fe_2O_3-Cr_2O_3-NiO system is fast during the initial period(reduction degree,α<38%),and then the rate decreases until the end of the reduction.Factors such as temperature,carbon content,sample size have a more significant effect during the final stage(α>38%).The metallic product formed at the initial stage(a Fe-Ni alloy)greatly promotes the reduction of Cr2O3 at the final stage.Further,during the reduction of Fe_2O_3-Cr_2O_3-NiO by carbon,interfacial reaction is the rate-controlling step and g(α)=1-(1-α)0.5 is the reaction mechanism for the initial stage,whereas two-dimensional diffusion is the rate-controlling step and f(α)=α+(1-α)ln(1-α)is the reaction mechanism for the final stage.The apparent activation energies are 55.43 k J/mol and 174.54 k J/mol for the initial and the final stages,respectively.

Optimized One-Step Preparation of a Bioactive Natural Product,Guaiazulene-2,9-dione

We previously isolated a natural product, namely guaiazulene-2,9-dione showing strong antibacterial activity against Vibrio anguillarum, from a gorgonian Muriceides collaris collected in South China Sea. In this experiment, guaiazulene-2,9-dione was quantitatively synthesized with an optimized one-step bromine oxidation method using guaiazulene as the raw material. The key reaction condition including reaction time and temperature, drop rate of bromine, concentration of aqueous THF solution, respective molar ratio of guaiazulene to bromine and acetic acid, and concentration of guaiazulene in aqueous THF solution, were investigated individually at five levels each for optimization. Combined with the verification test to show the absolute yield of each optimization step, the final optimal condition was determined as: when a solution of 0.025 mmol m L-1 guaiazulene in 80% aqueous THF was treated with four volumes of bromine at a drop rate of 0.1 m L min-1 and four volumes of acetic acid at-5℃ for three hours, the yield of guaiazulene-2,9-dione was 23.72%. This was the first report concerning optimized one-step synthesis to provide a convenient method for the large preparation of guaiazulene-2,9-dione.

Scientific Initiation： Meanings and Peculiarities of Public Policy in Brazil

This paper aims to analyze the Scientific Initiation （SI） as public policy of higher education in Brazil, from meanings and peculiarities of this device in the undergraduate academic＇s formation, created jointly with the National Research Council in 1951 currently National Council for Scientific and Technological Development （CNPq）. This corporation emerged from the recognition of the strategic importance of science and necessity of institutionalization of encouragement and fostering research. This is a theoretical bibliographical study and documentary that evidences the contributions and limits of SI while political science training should be part of academic activities to provide the development and support of investigative spirit. The concept of SI was established in universities as an activity to be developed in order to encourage the student to become familiar with scientific practices. The study concluded that SI is based on institutionalized norms within higher education to foster the development of science, and it is considered as an important strategy of expansion of graduate studies in Brazil.

Integration of urban and rural minimum living standard security system

With the acceleration of urbanization, the lifestyles and living expenses of farmers and urban residents is increasingly more and more similar .However, from the measures in terms of the minimum living guarantee, the level of protection of rural and urban residents really have a large gap. The Third Plenary Session of the 18th Central Committee noted ＂to promote urban and rural minimum living security system and rural development＂, ＂to speed up and improve the social security management system and operate the service system＂,These tell us that only to realize the integration of urban and rural subsistence allowances, improve the underpinning of the social security system, can we build a moderately prosperous society.

Research on Pension Insurance System under the Background of Aging

With the rapid development of economy in our country, the level of science and technology innovation, all of these prolong the life span of our life. Thus an aging population are increasingly highlight, which are deeply and widely influenced our society, economy, life and other aspects. As the basic insurance which maintain the elderly＇s life quality after they retired, Pension insurance will promove social stability and development. How to reform Pension insurance under the background of the aging of the population will get more and more attention from people. This article starts with the concept of the aging of the population and its development trend. Next, the article analyses the problems of Pension Insurance under the background of the aging of the population. Last, the article summarizes countermeasures according to solve these matters.

Preparation of nano-TiO_2 photocatalysts and their decomposition activity in phenol-contaminated water

ZiO2 was prepared by the hydrolyzation method in （NH4）2SO4-modified TiCl4 solution, and TiO2 photocatalysts were obtained by accelerating the precipitation of TiO2 powder in a high-temperature water bath. The photocatalysts were characterized by Brunauer-Emmett-Teller （BET）, X-ray diffraction （XRD）, Raman spectrum and UV-Vis （Ultraviolet-Visible） spectrometry techniques, and the photocatalytic activity in phenol-contaminated water was investigated. The results showed that photocatalysts calcined at 400 ℃ had a specific surface area of 138.2 m^2/g and an average particle size of 9 nm, and a significant increase in thermal stability of anatase phase. At the calcination temperature of 700 ~C, the crystal form of TiO2 started to change into rutile （anatase： 97%, rutile： 3%）. The activity of TiO2 photocatalysts prepared with （NH4）2SO4-modified TIC14 solution was markedly stronger than that without （NH4）2SOg-modified TIC14 solution. Maximal photocatalytic activity was observed at the mole ratio of Ti：（NH4）2SO4= 1：2, the water-bath temperature of 90℃ and the calcination temperature of 700 ℃.

3D ordered mesoporous cobalt ferrite phosphides for overall water splitting

Developing low-cost and earth-abundant electrocatalysts with high performance for electrochemical water splitting is a challenging issue. Herein, we report a facile and effective way to fabricate three-dimension(3D) ordered mesoporous Co1-xFexP(x=0, 0.25, 0.5, 0.75) electrocatalyst.Benefiting from 3D ordered mesoporous pore channels and composition optimization, the Co0.75Fe0.25 P exhibits excellent electrocatalytic activities with low overpotentials of 270 and 209 mV at 10 mA cm^-2 for oxygen evolution reaction(OER)and hydrogen evolution reaction(HER), respectively, in the alkaline electrolyte along with a durable electrochemical stability. In addition, as both the cathode and anode, the Co0.75Fe0.25P also exhibits superior electrolysis water splitting performance with only an applied voltage of 1.63 V to attain a current density of 10 m A cm^-2 without obvious decay for 18 h,indicating that the Co0.75Fe0.25P is an efficient electrocatalyst for overall water splitting.

Monitoring Soil Microbial Activities in Different Cropping Systems Using Combined Methods

Cropping activities may affect soil microbial activities and biomass,which would affect C and N cycling in soil and thus the crop yields and quality.In the present study,a combination of microcalorimetric,enzyme activity(sucrase,urease,catalase,and fluorescein diacetate hydrolysis),and real-time polymerase chain reaction(RT-PCR) analyses was used to investigate microbial status of farmland soils,collected from 5 different sites in Huazhong Agriculture University,China.Our results showed that among the 5sites,both positive and negative impacts of cropping activities on soil microbial activity were observed.Enzyme activity analysis showed that cropping activities reduced soil sucrase and urease activities,which would influence the C and N cycles in soil.Much more attentions should be given to microbial status affected by cropping activities in future.According to the correlation analysis,fluorescein diacetate hydrolysis showed a significantly(P < 0.05) negative correlation with the time to reach the maximum power output(R ——0.898),but a significantly(P < 0.05) positive correlation with bacterial gene copy number(R = 0.817).Soil catalase activity also showed a significantly(P < 0.05) positive correlation with bacterial gene copy number(R = 0.965).Using combined methods would provide virtual information of soil microbial status.