Carbon Dioxide Balance of Wood Substitution: Comparing Concrete- and Wood-Framed Buildings

In this study a method is suggested to compare the net carbon dioxide (CO₂) emission from the construction of concrete- and wood-framed buildings. The method is then applied to two buildings in Sweden and Finland constructed with wood frames, compared with functionally equivalent buildings constructed with concrete frames. Carbon accounting includes: emissions due to fossil fuel use in the production of building materials; the replacement of fossil fuels by biomass residues from logging, wood processing, construction and demolition; carbon stock changes in forests and buildings; and cement process reactions. The results show that wood-framed construction requires less energy, and emits less CO₂ to the atmosphere, than concrete-framed construction. The lifecycle emission difference between the wood- and concrete-framed buildings ranges from 30 to 130 kg C per m² of floor area. Hence, a net reduction of CO₂ emission can be obtained by increasing the proportion of wood-based building materials, relative to concrete materials. The benefits would be greatest if the biomass residues resulting from the production of the wood building materials were fully used in energy supply systems. The carbon mitigation efficiency, expressed in terms of biomass used per unit of reduced carbon emission, is considerably better if the wood is used to replace concrete building material than if the wood is used directly as biofuel.     

建筑行业环境保护与绿色施工

本文对建筑施工造成的环境污染及其危害性进行了分析,提出切实可行的文明施工、防止污染、新科技环保等综合措施,坚持可持续发展的科学发展观,发展文明施工、绿色施工.     

国内外军工材料环境试验现状及发展趋势

介绍军工材料环境试验对提高装备环境适应性的重要作用。从不同的技术方面,分析了国内外军工材料环境试验的现状、发展趋势以及主要差距。从规划的制定、新技术新方法的研发以及信息共享方面,提出设想。提出了目前需要研发新的环境试验、评价、管理方法和需要突破的关键技术。     

有机物分子结构与光催化氧化反应活性的关系

从正辛醇－水分配系数与Ｈａｍｍｅｔｔ常数，光催化氧化过程中的光解作用，表面活性剂的微环境效应及取代基的诱导效应等方面，探讨了有机物分子结构与其光催化氧化反应性之间的关系。     

Institutional and cost implications of multi-project baselines

Starting from a theoreticalnotion of capacity building this paperfocuses on the implications ofmulti-project baselines for costs andinstitutions. Availability of data and thelevel of data aggregation determine to alarge extent the cost of derivingmulti-project baselines. For localinstitutions this implies that theircapacity development needs are linked todecisions made on strictness of baselines.The initial higher costs of multi-projectcalculations in the development stage areeasily offset once more projects will usesuch a baseline. This paper argues theseinitial demands are not as high asexpected. Multi-project approaches willreduce transaction costs, especially forsmall-scale projects, will reducevalidation costs and likely reduce humanresource demands in other stages of theproject cycle.     

室内环境污染的防治及措施

分析了室内环境污染的原因以及室内污染对人类带来的危害，提出防护和改善室内环境质量的建议和措施。     

Efficient degradation of organic pollutants by S-NaTaO3/biochar under visible light and the photocatalytic performance of a permonosulfate-based dual-effect catalytic system

Removing large concentrations of organic pollutants from water efficiently and quickly under visible light is essential to developing photocatalytic technology and improving solar energy efficiency. This study used a simple hydrothermal method to prepare a non-metallic, S-doped NaTaO₃ (S-NTO) photocatalyst, which was then loaded onto biochar (BC) to form a S-NTO/BC composite photocatalyst. After uniform loading onto BC, the S-NTO particles transformed from cubic to spherical. The photogenerated electron-hole pair recombination probability of the composite photocatalyst was significantly lower than those of the NTO particles. The light absorption range of the catalyst was effectively widened from 310 nm UV region to visible region. In addition, a dual-effect catalytic system was constructed by introducing peroxymonosulfate (PMS) into the environment of the pollution to be degraded. The Rhodamine B, Methyl Orange, Acid Orange 7, tetracycline, and ciprofloxacin degradation efficiency at 40 mg/L reached 99.6%, 99.2%, 84.5%, 67.1%, and 70.7%, respectively, after irradiation by a 40 W lamps for 90 min. The high-efficiency visible-light catalytic activity of the dual-effect catalytic system was attributed to doping with non-metallic sulfur and loading of catalysts onto BC. The development of this dual-effect catalytic system provides new ideas for quickly and efficiently solving the problem of high-concentration organic pollution in aqueous environments, rationally and fully utilizing solar energy, and expanding the application of photocatalytic technology to practice.     

TiO2光催化剂载体及提高其光催化活性的研究进展

光催化技术是一种新型的绿色环保技术,TiO2是光催化反应中的一种研究较为广泛的光催化剂,其在污水处理以及空气净化等领域具有广泛的应用前景。文章综述了TiO2作为光催化剂的研究现状,着重介绍了TiO2光催化剂载体的研究及TiO2的改性研究。并结合我们在TiO2载体以及提高其催化活性方面所作的一些研究工作,提出一些看法。     

基于行业全产业链评估一份外卖订单的环境影响

构建"生产-运输-使用-废弃处置"的外卖全产业链，通过大样本企业调研与外卖平台大数据分析，计算8个样本城市不同材质与规格的外卖餐盒、餐具、包装袋的市场使用比例，挖掘骑手配送的海量数据，收集城市垃圾处理处置情况，系统评估外卖全过程的环境影响.结果表明，外卖包装物全产业链中生产环节（45%）与废弃处置环节（50%）为环境影响的主要来源，严重程度依次为固废排放、水污染、资源能源消耗和大气污染.所在城市及选用包装物材质的不同，外卖行业造成的环境影响会有显著区别，全产业链上的各环节需相互配合，多主体共同承担环境责任，采取差别化的减缓应对措施.     

In-situ-reduced synthesis of cyano group modified g-C3N4/CaCO3 composite with highly enhanced photocatalytic activity for nicotine elimination

Graphite carbon nitride has many excellent properties as a two-dimensional semiconductor material so that it has a wide application prospect in the field of photocatalysis. However, the traditional problems such as high recombination rate of photogenerated carriers limit its application. In this work, we introduce nitrogen deficiency into g-C₃N₄ to solve this problem a simple and safe in-situ reduction method. g-C₃N₄/CaCO₃ was obtained by a simple and safe one-step calcination method with industrial-grade micron particles CaCO₃. Cyano group modification was in-situ reduced during the thermal polymerization process, which would change the internal electronic structure of g-C₃N₄. The successful combination of g-C₃N₄ and CaCO₃ and the introduction of cyanide have been proved by Fourier transform infrared spectroscopy and X-ray photoelectron spectrometer. The formation of the cyano group, an electron-absorbing group, promotes the effective separation of photogenic electron hole pairs and inhibits the recombination of photogenic carriers. These advantages result in the generation of more •O₂⁻ and ¹O₂ in the catalytic system, which increases the photocatalytic efficiency of nicotine degradation by ten times. Furthermore, the degradation process of nicotine has been studied in this work to provide a basis for the degradation of nicotine organic pollutants in the air.