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中学教师专业标准下的“从实验学化学”课堂设计研究
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作者 徐晓林 《科教导刊(电子版)》 2015年第29期47-47,55,共2页
《中学教师专业标准(试行)》是国家对合格中学教师的基本要求,是中学教师进行教学活动的重要依据。在它的指导下,我将对“从实验学化学”章节进行课程设计,旨在对化学教师专业标准在教学课堂里的具体实施和体现进行简单的探讨。
关键词 专业标准 实验学化学 教学设计
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生命课堂视野下实验课堂教学案例研究以《苯酚》为例
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作者 蒋成 刘露露 邢丽琼 《科教导刊(电子版)》 2020年第6期151-152,共2页
本文以苯酚实验教学案例为例,在设计时通过巧妙设置问题引入实验,从生活中化学引入实验,抓住学生思维高峰,突破难点实验;注重教材二次设计,适当进行实验拓展,充分发挥了实验探究、教育功能,生命课堂教学理念得以彰显。
关键词 实验学化学 实验教育功能 实验设计 案例实践 生命课堂
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Computer Management of Quantitative Analysis Chemistry Experiment 被引量:8
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作者 Hairui Zhang Guofu Zhang +2 位作者 Qing Zhang Jianbo Cui Jianhong Qi 《Journal of Chemistry and Chemical Engineering》 2014年第2期176-179,共4页
The application of computer in the quantitative analysis chemistry experiment is a chemistry experiment teaching applications software, developed by Visual Basic (6.0), based on the content of quantitative analysis ... The application of computer in the quantitative analysis chemistry experiment is a chemistry experiment teaching applications software, developed by Visual Basic (6.0), based on the content of quantitative analysis chemistry experiment of chemistry major in higher institute. This software has the function of the automatic processing the experimental data, the automatic generation of test report copies, and the automatic evaluation of students' experimental results, which solve the reliability, objectivity and accuracy problems of the students' experiment data processing and evaluation, and avoid interference with human factors. The software has the characteristic of the easy installation, the easy operation, the strong practicability, pertinence, the systematicness and the running stability, so it provides a platform in the quantitative analysis chemistry experiment for the students' assessment system of automatic processing, and it has a high popularization value. The project's technical route design is reasonable, the research method is correct, and the experimental data processing results are reliable, which has reached the leading domestic level in the quantitative analysis chemistry experiment teaching field of computer data processing. And this project has been through the achievements appraisal of Gansu Provincial Sci. & Tech. Department. 展开更多
关键词 Computer language Visual Basic (6.0) experiment teaching software quantitative analysis chemistry experiment experiment data processing the experiment report copies grade evaluation.
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Effects of precipitation strengthening heat treatment for Al-Mg alloy 被引量:1
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作者 Seong-Jong KIM Seok-Ki JANG +2 位作者 Min-Su HAN Seong-Kwon KIM Jong-Sin KIM 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第6期1218-1224,共7页
The corrosions resulting from defects in painting layers frequently occur in Al alloys, so the application of corrosion preventing systems is also very important. Optimum conditions in terms of electrochemistry in rel... The corrosions resulting from defects in painting layers frequently occur in Al alloys, so the application of corrosion preventing systems is also very important. Optimum conditions in terms of electrochemistry in relation to solution treatment, quenching and artificial aging treatment were established in order to optimize precipitation strengthening conditions intended to enhance the strength of Al alloys. Slow strain rate tests (SSRT) at various applied potentials were conducted in potential range from -1.8 to 0.5 V. The results show that the maximum tensile strengths, elongations and time-to-fracture are shown to be high values. After precipitation strengthening heat treatment, a tendency appear that time-to-fracture increases as elongation increases. In the potential range from -1.3 V to -0.7 V, the specimens show excellent mechanical properties, and thus this range is considered to be a corrosion prevention range. 展开更多
关键词 Al alloy slow strain rate test ELECTROCHEMISTRY precipitation strengthening heat treatment mechanical property
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Formation and early development of tetraspores of Polysiphonia urceolata (Rhodomelaceae,Rhodophyta) 被引量:1
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作者 姚建亭 李大鹏 +2 位作者 于深辉 刘吉东 段德麟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第2期365-369,共5页
Polysiphonia urceolata is one type of potential commercial red seaweeds used for breeding and cultivation, because of its significant biochemical and biomedical application. However, the information of breeding and se... Polysiphonia urceolata is one type of potential commercial red seaweeds used for breeding and cultivation, because of its significant biochemical and biomedical application. However, the information of breeding and seedling incubation for cultivation is limited, especially the early development. In this study, tetrasporohyte and gametophyte of P. urceolata were taken as the study materials in Huiquan Bay, Qingdao, China. The cleaned and sterilized tetrasporophytes and gametophytes were pre-cultured in sterilized seawater, then nurtured at 18℃, 25 μmol photons m^-2 s^-1 in 12:12 h (light:dark) photoperiod. Continuous observation under microscope showed that the early development consists of bipolar division stage and seedling stage. In the division stage, tetraspores germinate into bipolar sporelings that further differentiate into a colorless rhizoidal portion and a lightly pigmented upright shoot. The lightly pigmented rhizoidal cell develops to a rhizoid and the larger pigmented cell transforms to an erect axis. In the seedling stage, several quasi-protuberances appear on the erect axis and form juvenile seedlings. The results demonstrate the culture of P. urceolata from tetraspores under laboratory conditions. 展开更多
关键词 Polysiphonia urceolata RHODOPHYTA early development TETRASPORE
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Physicochemical Characterization of Water of Bir M'Cherga Reservoir and Its Effluents
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作者 Yosra lsmail Abdalah Benalaya 《Journal of Environmental Science and Engineering(B)》 2012年第2期208-215,共8页
This study aims the physico-chemical characterization of surface water of the Bir M'Cherga reservoir and its effluents which are located in Zaghouan governorate of Tunisia. It required measures in situ of physicochem... This study aims the physico-chemical characterization of surface water of the Bir M'Cherga reservoir and its effluents which are located in Zaghouan governorate of Tunisia. It required measures in situ of physicochemical parameters and chemical analysis at laboratory of major element and nutritive salts. The results of this study revealed the presence of pollutants in the Miliane river at El Fahs area and the eutrophication of water in the Bit M'Cherga reservoir. According to the classification of Stuyfzand and Piper, water in the wadis of Melah, Hdada, Miliane and Boudebbane respectively is brackish, salty, extremely hard, chlorinated, sulphated, calcic, and magnesic. Water in the Bir M'Cherga reservoir is characterized by calcic facies chlorinated sulphated and sodic. Thus, the Bir M'Cherga reservoir presents a worrying situation and a risk of qualitative degradation of its water. 展开更多
关键词 Bit M'Cherga reservoir RIVERS eutofication POLLUTION geochemical study.
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Prediction of pyrolysis kinetic parameters from biomass constituents based on simplex-lattice mixture design 被引量:1
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作者 Panusit Sungsuk Sasiporn Chayaporn +3 位作者 Sasithorn Sunphorka Prapan Kuchonthara Pornpote Piumsomboon Benjapon Chalermsinsuwan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第4期535-542,共8页
The aim of this study is to determine the effect of the main chemical components ofbiomass: cellulose, hemicel- lulose and lignin, on chemical kinetics ofbiomass pyrolysis. The experiments were designed based on a si... The aim of this study is to determine the effect of the main chemical components ofbiomass: cellulose, hemicel- lulose and lignin, on chemical kinetics ofbiomass pyrolysis. The experiments were designed based on a simplex- lattice mixture design. The pyrolysis was observed by using a thermogravimetric analyzer. The curves obtained from the employed analytical method fit the experimental data (R2 〉 0.9). This indicated that this method has the potential to determine the kinetic parameters such as the activation energy (E~), frequency factor (A) and re- action order (n) for each point of the experimental design. The results obtained from the simplex-lattice mixture design indicated that cellulose had a significant effect on Ea and A, and the interaction between cellulose and lignin had an important effect on the reaction order, n. The proposed models were then proved to be useful for predicting pyrolysis behavior in real biomass and so could be used as a simple approximation for predicting the overall trend of chemical reaction kinetics. 展开更多
关键词 BiomassPyrolysisSimplex-lattice mixture designKineticsModeling
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A new two-dimensional experimental apparatus for electrochemical remediation processes
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作者 顾莹莹 付融冰 +1 位作者 李鸿江 安慧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第8期1389-1397,共9页
Electrochemical extraction of contaminants from soils is a promising soil decontamination technology. Various experiments have been conducted to study electrochemical reactions and geochemical processes in the electro... Electrochemical extraction of contaminants from soils is a promising soil decontamination technology. Various experiments have been conducted to study electrochemical reactions and geochemical processes in the electrochemical extraction using different experimental apparatuses. This paper presents the development of a new closed two-dimensional(2D) apparatus that can better simulate the field application of the technology and accurately monitor the most important electrochemical parameters to understand the process. The innovative features of the new apparatus include the outer and inner electrodes designed to apply a non-uniform electrical field across the specimen as in the field electrochemical remediation process, the probes installed to measure the 2D distribution of electrical voltage, and the gas and fluid volume measurement devices used to accurately monitor the gas generation and electroosmotic flow rates at both electrodes as a function of time. The components of this new apparatus and the features of each component are described. The operating procedure and some typical results from three experiments with the apparatus are demonstrated. The results show that the variation of the gas generation rate is in good agreement with the electric current. Their relation provides a valid evaluation for electrochemical behavior of the system and Faraday's laws of electrolysis. The 2D profiles of cadmium concentration and voltage distribution at the end of the experiment reveal the great effects of a non-uniform electrical field on the contaminant mobilization. 展开更多
关键词 Electrochemical extraction 2D experimental apparatus Non-uniform electrical field Gas generation rate
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Prevalence of sensitization to weed pollens of Humulus scandens,Artemisia vulgaris,and Ambrosia artemisiifolia in northern China 被引量:6
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作者 Guo-dong HAO Yi-wu ZHENG +6 位作者 Birgitte GJESING Xing-ai KONG Jing-yuan WANG Zhi-jing SONG Xu-xin LAI Nan-shan ZHONG Michael D.SPANGFORT 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2013年第3期240-246,共7页
Objective:Weed pollens are common sources of allergens worldwide.The prevalence of weed pollen sensitization is not yet fully known in China.The purpose of this study was to investigate the prevalence of sensitization... Objective:Weed pollens are common sources of allergens worldwide.The prevalence of weed pollen sensitization is not yet fully known in China.The purpose of this study was to investigate the prevalence of sensitization to weed allergens from Artemisia,Ambrosia,and Humulus in northern China.Methods:A total of 1144 subjects(aged from 5 to 68 years) visiting our clinic from June to October 2011 underwent intradermal testing using a panel of 25 allergen sources.Subjects with positive skin responses to any pollen were further tested for their serum concentrations of IgE antibodies against Artemisia vulgaris,Ambrosia artemisiifolia,and Humulus scandens,and against the purified allergens,Art v 1 and Amb a 1.Results:Of 1144 subjects,170 had positive intradermal reactions to pollen and 144 donated serum for IgE testing.The prevalence of positive intradermal responses to pollens of Artemisia sieversiana,Artemisia annua,A.artemisiifolia,and H.scandens was 11.0%,10.2%,3.7%,and 6.6%,respectively.Among the intradermal positive subjects,the prevalence of specific IgE antigens to A.vulgaris was 58.3%,to A.artemisiifolia 14.7%,and to H.scandens 41.0%.The prevalence of specific IgE antigens to the allergen Art v 1 was 46.9%,and to Amb a 1 was 11.2%.The correlation between the presence of IgE antibodies specific to A.vulgaris and to the Art v 1 antigen was very high.Subjects with A.artemisiifolia specific IgE also had A.vulgaris specific IgE,but with relatively high levels of A.vulgaris IgE antibodies.There were no correlations between the presence of IgE antibodies to H.scandens and A.vulgaris or to H.scandens and A.artemisiifolia.Conclusions:The intradermal prevalence of weed pollen sensitization among allergic subjects in northern China is about 13.5%.Correlations of specific IgE antibodies suggest that pollen allergens from Artemisia and Humulus are independent sources for primary sensitization. 展开更多
关键词 Humulus scandens Artemisia vulgaris Ambrosia artemisiifolia Intradermal test Specific IgE SENSITIZATION
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Experimental evolution, behavior and genetics: Associative learning as a case study 被引量:1
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作者 Elisabetta VERSACE 《Current Zoology》 SCIE CAS CSCD 2015年第2期226-241,共16页
The evolutionary dynamics of behavioral traits reflect phenotypic and genetic changes. Methodological difficulties in analyzing the genetic dynamics of complex traits have left open questions on the mechanisms that ha... The evolutionary dynamics of behavioral traits reflect phenotypic and genetic changes. Methodological difficulties in analyzing the genetic dynamics of complex traits have left open questions on the mechanisms that have shaped complex beha- viors and cognitive abilities. A strategy to investigate the change of behavior across generations is to assume that genetic con- straints have a negligible role in evolution (the phenotypic gambit) and focus on the phenotype as a proxy for genetic evolution. Empirical evidence and technologic advances in genomics question the choice of neglecting the genetic underlying the dynamics of behavioral evolution. I first discuss the relevance of genetic factors - e.g. genetic variability, genetic linkage, gene interactions - in shaping evolution, showing the importance of taking genetic factors into account when dealing with evolutionary dynamics. I subsequently describe the recent advancements in genetics and genomics that make the investigation of the ongoing evolutionary process of behavioral traits finally attainable. In particular, by applying genomic resequencing to experimental evolution - a me- thod called Evolve & Resequence - it is possible to monitor at the same time phenotypic and genomie changes in populations exposed to controlled selective pressures. Experimental evolution of associative learning, a well-known trait that promptly re- sponds to selection, is a convenient model to illustrate this approach applied to behavior and cognition. Taking into account the recent achievements of the field, I discuss how to design and conduct an effective Evolve & Resequence study on associative learning in Drosophila. By integrating phenotypic and genomic data in the investigation of evolutionary dynamics, new insights can be gained on longstanding questions such as the modularity of mind and its evolution . 展开更多
关键词 Experimental evolution BEHAVIOR GENOMICS Evolve and Resequence LEARNING Drosophila.
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Electrochemical behavior and electrowinning of palladium in nitric acid media 被引量:3
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作者 LIU ShengChu WEI YueZhou +1 位作者 LIU RuiQin FANG BaiZeng 《Science China Chemistry》 SCIE EI CAS 2013年第12期1743-1748,共6页
In this study,the electrochemical behavior of Pd(II)in nitric acid media was investigated using various electrochemical techniques.By analyzing the cyclic voltammogram of Pd(II)recorded at Pt electrode,a series of ele... In this study,the electrochemical behavior of Pd(II)in nitric acid media was investigated using various electrochemical techniques.By analyzing the cyclic voltammogram of Pd(II)recorded at Pt electrode,a series of electrochemical reactions associated with palladium were recognized,indicating that Pd(II)undergoes a single step two-electrons irreversible process.Electroreduction reaction of Pd(II)and auto-catalytic reactions of nitrous acid are supposed to play a leading role in low and high concentrations of nitric acid,respectively.Stirring could facilitate the reduction of Pd(II)in relatively low nitric acid concentration(3 mol/L).The value of charge transfer coefficient was determined to be 0.18 for the measurements at 298 K.The diffusion coefficient of Pd(II)increased from 1.89×10 8cm2/s at 288 K to 4.23×10 8cm2/s at 318 K,and the activation energy was calculated to be 21.5 kJ/mol.In electrowinning experiments,SEM images of palladium obtained by electrolysis reveal the dendrite growth in all cases,which is uniform all over the entire surface of Pt electrode.The recovery ratios of Pd at different nitric acid concentrations are high,and the faradic efficiency of electrolysis decreases with increasing the nitric acid concentration.When stirring was introduced during electrolysis,the electrodeposition rate of Pd increased substantially. 展开更多
关键词 PALLADIUM high-level liquid waste electrochemical technique ELECTROWINNING
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