BrCF_2SO_2Br, prepared from sulfinatodehalogenation of CF_2Br_2 followed by bromination of the intermediate BrCF_2SO_2Na, was shown to be a mild and efficient bromodifluoromethylating agent.
The elliptic mild slope equation is used to simulate linear wave propagation over variable sea bed topography with mild slopes. The governing equation is discretized by the finite difference method. Based on the BI-CG...The elliptic mild slope equation is used to simulate linear wave propagation over variable sea bed topography with mild slopes. The governing equation is discretized by the finite difference method. Based on the BI-CGSTAB technique, an attractive variant bf BI-Conjugate Gradients (BI-CG) method, the obtained linear algebraic system of equations is solved. Numerical experiments show that the BI-CGSTAB method is efficient for solving the elliptic mild slope equation. The results obtained by the BI-CGSTAB-Based method are much the same as those obtained by other authors with different solution methods, but the convergence rate is much faster than that of other methods.展开更多
The mild-slope equation derived by Berkhoff (1972), has widely been used in the numerical calculation of refraction and diffraction of regular waves. However, it is well known that the random sea waves has a significa...The mild-slope equation derived by Berkhoff (1972), has widely been used in the numerical calculation of refraction and diffraction of regular waves. However, it is well known that the random sea waves has a significant effect in the refraction and diffraction problems. In this paper, a new form of time-dependent mild slope equation for irregular waves was derived with Fade approximation and Kubo's time series concept. The equation was simplified using WKB method, and simple and practical irregular mild slope equation was obtained. Results of numerical calculations are compared with those of laboratory experiments.展开更多
Using the slot method, the moving boundary problem caused by the change of the tide water elevation is treated. A two-dimensional advection - diffusion model with moving boundary is proposed, and the input pollutant i...Using the slot method, the moving boundary problem caused by the change of the tide water elevation is treated. A two-dimensional advection - diffusion model with moving boundary is proposed, and the input pollutant is considered as moving source to meet the water level variation. The model given in this paper has been used to simulate the pollutant transport in the Bohai Gulf, the computational results are in good agreement with the measured data.展开更多
A case of household water tanks, 1000 L capacity, made of RCC, LLDPE and mild steel (stainless steel) was evaluated for life cycle analysis. The scope of the research comprised of the raw materials, energy inputs and ...A case of household water tanks, 1000 L capacity, made of RCC, LLDPE and mild steel (stainless steel) was evaluated for life cycle analysis. The scope of the research comprised of the raw materials, energy inputs and corresponding emissions during all phases of product making such as extraction of raw material, it’s processing, followed by manufacturing and transport, as well as use and reuse of the product. Simapro 8 (System for Integrated environMental Assessment of PROducts), a modelling software, from Dutch PRé Consultants was used to conduct the life cycle analysis. Simapro 8 enables systematic and transparent modelling and analysis of complex life cycles based on the recommendations of the ISO 14040 series of standards. In the present study the most common method which is acceptable worldwide “Recipe Endpoint method” (ReCiPe) was employed. ReCiPe computes the impact categories and classifies them into two classes based on relevant arrays of characterization factors. Simapro addresses impact categories viz. ozone depletion, human toxicity, ionizing radiation, photochemical oxidant formation, particulate matter formation, terrestrial acidification, climate change, terrestrial ecotoxicity, agricultural land occupation, urban land occupation, natural land transformation, marine ecotoxicity, marine eutrophication, fresh water eutrophication, fresh water ecotoxicity, fossil fuel depletion, minerals depletion, fresh water depletion at the midpoint level. While at the Endpoint level, the impact categories are multiplied by corresponding damage factors and integrated to be represented as three Endpoint level categories, viz. human health, ecosystems and resource depletion. The three endpoint categories are normalized, weighted, and aggregated into a single score. LCA studies indicate that household water tanks of LLDPE have least environmental implications considering impacts on human health, ecosystems and resource depletion as compared to its counterparts viz. Household water tanks made up of mild steel and RCC. The sequence of the material with decreasing impacts is concrete tanks > mild steel tank > LLDPE tanks. The overall assessment is centred on the elements such as material inputs, energy inputs and environmental emissions.展开更多
目的:构建针对脾肾亏虚型轻度认知障碍患者的经络拍打方案。方法:检索中国知网、万方数据库、维普数据库、PubMed、Web of Science、读秀学术搜索从建库至2022年12月,通过文献研究法确定脾肾亏虚型轻度认知障碍患者经络拍打方案的初稿,...目的:构建针对脾肾亏虚型轻度认知障碍患者的经络拍打方案。方法:检索中国知网、万方数据库、维普数据库、PubMed、Web of Science、读秀学术搜索从建库至2022年12月,通过文献研究法确定脾肾亏虚型轻度认知障碍患者经络拍打方案的初稿,遴选来自陕西省、广东省、广西壮族自治区、湖北省、福建省、山东省、湖南省、四川省的21名专家进行2轮问卷函询。结果:两轮专家积极系数分别为100.0%和95.2%,权威程度分别为0.89、0.90,协调系数分别为0.407、0.349,经χ2检验,差异均有统计学意义(P<0.001),同时运用成分分析法进行一致性检验,一致性比例均<0.1。最终形成脾肾亏虚型轻度认知障碍患者经络拍打方案,包括2个一级指标、7个二级指标、12个三级指标。结论:本研究构建的方案有一定科学性和实用性,可为脾肾亏虚型轻度认知障碍患者进行经络拍打治疗提供参考。展开更多
文摘BrCF_2SO_2Br, prepared from sulfinatodehalogenation of CF_2Br_2 followed by bromination of the intermediate BrCF_2SO_2Na, was shown to be a mild and efficient bromodifluoromethylating agent.
基金National Natural Science Foundation of China under grant No.59839330China Postdoctoral Science Foundation
文摘The elliptic mild slope equation is used to simulate linear wave propagation over variable sea bed topography with mild slopes. The governing equation is discretized by the finite difference method. Based on the BI-CGSTAB technique, an attractive variant bf BI-Conjugate Gradients (BI-CG) method, the obtained linear algebraic system of equations is solved. Numerical experiments show that the BI-CGSTAB method is efficient for solving the elliptic mild slope equation. The results obtained by the BI-CGSTAB-Based method are much the same as those obtained by other authors with different solution methods, but the convergence rate is much faster than that of other methods.
基金The research was financially supported by the Doctor degree Program Foundation of State Education Commission of China
文摘The mild-slope equation derived by Berkhoff (1972), has widely been used in the numerical calculation of refraction and diffraction of regular waves. However, it is well known that the random sea waves has a significant effect in the refraction and diffraction problems. In this paper, a new form of time-dependent mild slope equation for irregular waves was derived with Fade approximation and Kubo's time series concept. The equation was simplified using WKB method, and simple and practical irregular mild slope equation was obtained. Results of numerical calculations are compared with those of laboratory experiments.
文摘Using the slot method, the moving boundary problem caused by the change of the tide water elevation is treated. A two-dimensional advection - diffusion model with moving boundary is proposed, and the input pollutant is considered as moving source to meet the water level variation. The model given in this paper has been used to simulate the pollutant transport in the Bohai Gulf, the computational results are in good agreement with the measured data.
文摘A case of household water tanks, 1000 L capacity, made of RCC, LLDPE and mild steel (stainless steel) was evaluated for life cycle analysis. The scope of the research comprised of the raw materials, energy inputs and corresponding emissions during all phases of product making such as extraction of raw material, it’s processing, followed by manufacturing and transport, as well as use and reuse of the product. Simapro 8 (System for Integrated environMental Assessment of PROducts), a modelling software, from Dutch PRé Consultants was used to conduct the life cycle analysis. Simapro 8 enables systematic and transparent modelling and analysis of complex life cycles based on the recommendations of the ISO 14040 series of standards. In the present study the most common method which is acceptable worldwide “Recipe Endpoint method” (ReCiPe) was employed. ReCiPe computes the impact categories and classifies them into two classes based on relevant arrays of characterization factors. Simapro addresses impact categories viz. ozone depletion, human toxicity, ionizing radiation, photochemical oxidant formation, particulate matter formation, terrestrial acidification, climate change, terrestrial ecotoxicity, agricultural land occupation, urban land occupation, natural land transformation, marine ecotoxicity, marine eutrophication, fresh water eutrophication, fresh water ecotoxicity, fossil fuel depletion, minerals depletion, fresh water depletion at the midpoint level. While at the Endpoint level, the impact categories are multiplied by corresponding damage factors and integrated to be represented as three Endpoint level categories, viz. human health, ecosystems and resource depletion. The three endpoint categories are normalized, weighted, and aggregated into a single score. LCA studies indicate that household water tanks of LLDPE have least environmental implications considering impacts on human health, ecosystems and resource depletion as compared to its counterparts viz. Household water tanks made up of mild steel and RCC. The sequence of the material with decreasing impacts is concrete tanks > mild steel tank > LLDPE tanks. The overall assessment is centred on the elements such as material inputs, energy inputs and environmental emissions.
文摘目的:构建针对脾肾亏虚型轻度认知障碍患者的经络拍打方案。方法:检索中国知网、万方数据库、维普数据库、PubMed、Web of Science、读秀学术搜索从建库至2022年12月,通过文献研究法确定脾肾亏虚型轻度认知障碍患者经络拍打方案的初稿,遴选来自陕西省、广东省、广西壮族自治区、湖北省、福建省、山东省、湖南省、四川省的21名专家进行2轮问卷函询。结果:两轮专家积极系数分别为100.0%和95.2%,权威程度分别为0.89、0.90,协调系数分别为0.407、0.349,经χ2检验,差异均有统计学意义(P<0.001),同时运用成分分析法进行一致性检验,一致性比例均<0.1。最终形成脾肾亏虚型轻度认知障碍患者经络拍打方案,包括2个一级指标、7个二级指标、12个三级指标。结论:本研究构建的方案有一定科学性和实用性,可为脾肾亏虚型轻度认知障碍患者进行经络拍打治疗提供参考。
