Towards the Prediction of Heat and Mass Transfer in an Air-Conditioned Environment for a Life Support System in Space

Long-term flights or the establishment of permanent bases in space provide serious challenges for life support systems. Plants are essential companion life forms for such space missions, where human habitats must mimic the cycles of life on earth to generate and recycle food, oxygen and water. Nowadays, the chemical–mechanical recycling systems used in the international space station are much more compact, less labour intensive and more reliable than plant-based systems, but these systems would be too expensive for the long-term human exploration. In order to improve living conditions for humans and plants, we need an accurate characterisation of the mass transfer phenomena related to condensation of humid air. We are interested in developing an experimental protocol, which would help us to establish a theoretical model describing the heterogeneous transfers along a wall or a plant in an air-conditioned environment. Initially, we started in dry conditions by measuring the velocity profiles within the boundary layer that develop on a horizontal or a vertical flat plate in a wind tunnel. The velocity ranged from 0.5 to 2.5 m s^?1. Existing coupled heat and mass transfer measurement results relevant to our applications are discussed.     

Environmental friendly automated line for recovering the cabinet of waste refrigerator

A large amount of hazardous trichloromonofluoromethane (CFC-11) is contained in the polyurethane (PUR) foam of refrigerator cabinet. How to recover the cabinet of waste refrigerator with environmental awareness has been the pressing problem in the treatment of waste refrigerator. The published literature of waste refrigerator cabinets recovering mainly focuses on policy making and conceptual design. Little information relates to the production line of waste refrigerator cabinet recovering and its detailed operation, which is the urgent needed literature. In this paper, an environmental friendly production line for recovering the cabinet of waste refrigerators was reported for helping enterprise or government to construct line to recover the obsolete refrigerators. It included closed shearing process, activated carbon fiber absorption (ACFA) process, air current separation, and magnetic/eddy current separation. The optimized operating parameters of every process were obtained from the experiments. Then, experiment of recovering 50 waste refrigerator cabinets by the production line was performed in factory. Mass balances of the recovered materials were carried out. The result shown the recovery rate of waste refrigerator cabinet could reach 97.6%. Finally, comparison between the production line and other recovery technologies was made. The results indicated that the proposed line provided environment-friendly recovery of waste refrigerator cabinets while achieving low cost of production.     

Environmental friendly leaching reagent for cobalt and lithium recovery from spent lithium-ion batteries

We investigated an environmentally friendly leaching process for the recovery of cobalt and lithium from the cathode active materials of spent lithium-ion batteries. The easily degradable organic acid DL-malic acid (C₄H₅O₆) was used as a leaching reagent. The structural, morphology of the cathode materials before and after leaching were characterized by X-ray diffraction (XRD) and scanning electronic microscopy (SEM). The amount of Co and Li present in the leachate was determined by atomic absorption spectrophotometry (AAS). Conditions for achieving a recovery of more than 90 wt.% Co and nearly 100 wt.% Li were determined experimentally by varying the concentrations of leachant, time and temperature of the reaction as well as the initial solid-to-liquid ratio. We found that hydrogen peroxide in a DL-malic acid solution is an effective reducing agent because it enhances the leaching efficiency. Leaching with 1.5 M DL-malic acid, 2.0 vol.% hydrogen peroxide and a S:L of 20 g L^?1 in a batch extractor results in a highly efficient recovery of the metals within 40 min at 90 °C.     

甘泉铁路建设资源节约型、环境友好型企业管理体系的思考

甘泉铁路作为从事煤炭输送、分配与服务等活动的国际能源通道运输企业,高度重视建设资源节约型、环境友好型企业.根据煤炭运输企业的机构特点以及资源利用模式,提出甘泉铁路建设资源节约、环境友好企业,建立二级管理组织模式、配套机制的实施建议.     

Scaling and Mapping Regional Calculations of Soil Chemical Weathering Rates in Sweden

Weathering rates of base cations are crucial in critical load calculations and assessments of sustainable forestry. The weathering rate on a single site with detailed geological data can be modelled using the PROFILE model. For environmental assessments on a regional scale, the weathering rates for sites are scaled into regional maps. The step from sites to regional level requires focus on the spatial variation of weathering rates. In this paper, a method is presented by which weathering rates are calculated for 25589 Swedish sites with total elemental analysis for the soil. Based on a part of the results, a methodology for creating area covering maps by geostatistical analysis and kriging is described. A normative reconstruction model was used to transform total elemental analysis to mineralogy. Information from the Swedish Forest Inventory database and other databases were used to derive texture and other important information for the sites, e.g. climate, deposition and vegetation data. The calculated weathering rates show a regional pattern that indicates possibilities for interpolation of data in large parts of Sweden. Geostatistical analysis of an area in southern Sweden shows different properties for different base cations. Kriging was performed for potassium to demonstrate the method. It was concluded that different base cations and different regions have to be analysed separately, in order to optimise the kriging method.     

Biodegradability of a Selected Range of Polymers and Polymer Blends and Standard Methods for Assessment of Biodegradation

Synthetic polymers are important to the packaging industry but their use raises aesthetic and environmental concerns, particularly with regard to solid waste accumulation problems and the threat to wildlife. Some concerns are addressed by attention to problems associated with source reduction, incineration, recycling and landfill. Others are addressed by the development of new biodegradable polymers either alone or in blends. Materials used for biodegradable polymers include various forms of starch and products derived from it, biopolyesters and some synthetic polymers. Starch is rapidly metabolised and is an excellent base material for polymer blends or for infill of more environmentally inert polymers where it is metabolised to leave less residual polymer on biodegradation. This should help to improve the environmental impact of waste disposal. A number of standard methods have been developed to estimate the extent of biodegradability of polymers under various conditions and with a variety of organisms. They tend to be used mainly in the countries where they were developed but there is much overlap between the standards of different countries and wide scope for development of consistent and international standards.     

炼化企业SO2减排潜力分析

介绍了炼化企业的SO2排放源,建立了自备电厂SO2减排量数学模型,研究了SO2减排量对各影响因素的敏感度,分析了炼化企业SO2减排潜力.自备电厂燃煤锅炉SO2减排措施包括:增设脱硫设施,改进现有脱硫工艺,提高脱硫效率;关停小机组;降低燃料中硫含量.生产过程中催化裂化催化剂再生烟气的脱硫减排措施包括:降低原料硫含量;使用...     

Behaviour of Rice-Byproducts and Optimizing the Conditions for Production of High Performance Natural Fiber Polymer Composites

This present study deals with evaluating some available rice by-products, such as rice straw and rice husks, as a fiber component in manufacturing of high performance natural fiber polymer composites (NFPC). The utilization of these undesirable wastes will contribute to the reduction of the environmental impact of waste disposal by burning. Two matrices (thermoset and thermoplastic) were used. Optimization of manufacture conditions of polyester-based thermosetting polymer composites was carried out through examine the effects of fibers to polymer ratio, amounts of catalyzed and initiator, fraction size of fibers and substituting one fibers by another, as well as time, temperature and pressure of pressing. The possibility of styrene containing polyester solution on improving the fiber interface via in situ grafting and enhancing the strength and water resistance of the produced NFPC was also evaluated, in comparison with that produced from using thermoplastic matrix (polypropylene) in presence of coupling agent. The production of this valuable product (NFPC) by this simple procedure, which not needs special devices (twin extrusion with heater), and chemicals to improve the compatibility between fibers and polymer matrix, will ensure reasonable profits and direct impacts on the Egyptian economy in general and rice growers in particular.     

《火力发电厂锅炉烟气袋式除尘器滤料滤袋技术条件》标准解读

主要介绍了电力行业新标准《火力发电厂锅炉烟气袋式除尘器滤料滤袋技术条件》（DL／T1175—2012）的修订背景及主要内容,重点分析了针对火电行业应用的袋式除尘滤料纤维、基布、缝纫线等重要指标,并对今后的标准化发展进行了展望。     

Polymer Supported Calix[4]Arene Derivatives for the Extraction of Metals and Dichromate Anions

Three newly synthesized polymer supported calix[4]arene ionophores (7–9) were synthesized, and their ion binding properties toward selected alkali (Li⁺, Na⁺, K⁺, Cs⁺) and transition metal (Hg²⁺, Ni²⁺, Cu²⁺, Co²⁺, Cd²⁺, and Pb²⁺) cations were investigated. It has been observed that these ionophores are not selective toward a particular metal cation but show better ion binding property as compared to monomeric calixarene derivatives (2 and 6). Ionophore 6 and its supported polymer were also employed in dichromate anion extraction experiments. The polymeric ionophore (9) was found an effective extractant for dichromate anion even at pH 7.     

一种新型聚合物分散剂的制备及表征

以甲基丙烯酸和丙烯磺酸钠为单体、过硫酸铵溶液为引发剂合成聚合物分散剂（PMS）。最佳合成条件：单体总质量为60g,甲基丙烯酸和丙烯磺酸钠的摩尔比为3．0,过硫酸铵溶液加入量为12g,亚硫酸氢钠加入最为1g,反应温度为75℃。对最佳条件下制得的PMS进行应用实验,当100g陶瓷氧化铝粉末中PMS加入量为0．5g时,浆料的黏度较小,分散效果良好。PMS属于非品态聚合物,热稳定性良好,相对分子质量为2127。     

On the Calculation and Interpretation of Target Load Functions

In this study critical load functions and target load functions of nitrogen and sulphur deposition with respect to acidity and minimum base cation to aluminium ratio were calculated with the SAFE model using three different averaging strategies: (1) averaging based on current forest generation, (2) averaging based on next generation and (3) averaging based on the entire simulation period. From the results it is evident that although target load calculation and indeed critical load calculation is straight forward, there is a problem in translating a predicted recovery according to the target load calculation back to a site-specific condition. We conclude that a policy strategy for emission reductions that ensures recovery, according to calculated target load functions, is likely to be beneficial from an ecosystem point of view. However, such a strategy may not be sufficient to achieve actual non-violation of the chemical criteria throughout the seasonal or rotational variations. To address this issue we propose a method for calculating dynamic critical loads which ensures that the chosen criteria is not violated.     

Emission of Volatiles from Polymers — A New Approach for Understanding Polymer Degradation

Emission of low molar mass compounds from different polymeric materials was determined and the results from the volatile analysis were applied to predict the degree of degradation and long-term properties, to determine degradation rates and mechanisms, to differentiate between biotic and abiotic degradation and for quality control work. Solid-phase microextraction and solid-phase extraction together with GC-MS were applied to identify and quantify the low molar mass compounds. Volatiles were released and monitored at early stages of degradation before any matrix changes were observed by e.g. SEC, DSC and tensile testing. The analysis of volatiles can thus also be applied to detect small differences between polymeric materials and their susceptibility to degradation. The formation of certain degradation products correlated with the changes taking place in the polymer matrix, these indicator products could, thus, be analysed to rapidly predict the degree of degradation in the polymer matrix and further to predict the long-term properties and remaining lifetime of the product.     

中国食品企业环境友好现状分析——以河南、四川与青海三省为例

近年来,中国食品企业发展迅猛,受经济利益驱使不断扩大生产,大肆掠夺自然界的资源,导致诸多企业可持续发展能力不断下降。对此,引入层次分析法(AHP)对中国食品工业大省——河南、四川和青海省的环境友好情况评价指标的权重进行确定,并通过各指标的线性加权,对该地食品企业的环境友好状况进行量化,与全国食品企业环境友好状况进行比对,以期了解中国食品工业大省的环境友好现状,并希望通过采取有效措施加强企业生产环境控制,提升社会效益。     

Development of a Safe Solid-State Microorganism/Biodegradable Polymer Composite for Decomposition of Formaldehyde

A very safe and environmentally friendly solid-state material for bioremediation was prepared using a combination of Aspergillus oryzae and poly(ε-caprolactone) (PCL), a porous biodegradable polymer. The novel material was capable of decomposing 200 ppm formaldehyde solutions to 0 ppm within 7 days. Degradation ability was prolonged by addition of yeast extract-peptone-dextrose medium into the composite; 200 ppm formaldehyde was decomposed to 0 ppm over eight additional decomposition cycles and 100 days. A unique mechanism is proposed where, during PCL degradation, the solid-state composite provides nutrients to A. oryzae.     

Encapsulation of Nerol Oil in Polycaprolactone Polymer and Stability Evaluation

Journal of Polymers and the Environment - The objective of this study was to obtain and characterize Nerol essential oil encapsulated in PCL. The miniemulsion and solvent evaporation method was...     

A New Respirometric Test Simulating Soil Burial Conditions for the Evaluation of Polymer Biodegradation

A new convenient and reliable method is described for assessing the biodegradation properties of polymeric materials under simulated soil burial conditions, which makes it possible to test with nutrient-rich soils. This method consists of the utilization of a minimum amount of a soil layer, in which the samples to be tested are set in close contact, sandwiched between two layers of perlite, a natural porous aluminosilicate. The biodegradation level is monitored by determining the carbon dioxide evolution derived from the test samples. The limited amount of soil used limits carbon dioxide evolution from the blanks, due to the corresponding limited overall amount of soil carbon. This experimental setup allows for an extremely satisfactory level of confidence in the analytical results, permitting a wider variety of soil types to be tested.     

Influence for Soil Environment by Continuing use of Biodegradable Plastic

The influence on soil environment by continuing use of the biodegradable plastic films (biodegradable mulching films) in farmland was investigated. The difference was not seen in the amount of soil bacteria between mulching film plowing sections and non-plowing sections. The total bacteria amount did not increase by the effect of plowing the biodegradable mulching film. Poly-(butylene succinate and adipate) (PBSA) and poly-(ε-caprolactone) (PCL) decomposing bacteria did not increase in PBSA and PCL mulching film plowing sections comparing polyethylene covering section (PE) and no-film section. Polylactic acid (PLA) decomposing bacteria were not detected in all sections. Total denaturing gradient gel electrophoresis (DGGE) band patterns did not show a clear transition of the bacterial community structure in both the cultivating and promoting sections. In usual usage condition of the biodegradable plastic films, it was hardly influence to the soil environment such as bacterial community structure in farmland.     

Characterization of Sorghum Bran/Recycled Low Density Polyethylene for the Manufacturing of Polymer Composites

The objective of the study was to investigate the suitability of using sorghum bran in recycled low density polyethylene (R-LDPE) composites manufacturing. In response to the disposal of environmental problematic agricultural and polymer waste, composite sheets using recycled low density polyethylene and sorghum bran of different loadings (5, 10, 15 and 20 wt%) were prepared by melt compounding and compression molding. The effects of sorghum bran loadings on the mechanical, thermal, water absorption, swelling and crystalline properties of the composites were determined. Characterization of composites was carried out using X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermo gravimetric (TGA/DTG) and mechanical analyses. It was found that increasing fiber loadings resulted to increased moduli and tensile strength while hardness was decreased. XRD indicated that fiber addition to R-LDPE did not change characteristic peak position. DSC results showed that the R-LDPE had significantly larger peak heat flow during cooling run than the blank R-LDPE, showing higher crystallization rates for R-LDPE. The results obtained confirmed that sorghum bran particles showed some potential as a good reinforcement in polymer matrix composites and indicate its thermal stability for possibly future composite applications.     

Low‐Capacity Well Pairs for Treating Contaminated Groundwater in Homogeneous and Heterogeneous Aquifers

Groundwater remediation alternatives were simulated for homogeneous and heterogeneous aquifers with a numerical mass transport model. Low‐energy alternatives involved an injection–extraction well pair positioned along a downgradient linear transect. This transect was located 5 m from the contaminant plume and oriented perpendicular to the regional hydraulic gradient. Through numerous trials, for one homogeneous and three heterogeneous settings, the model identified an optimal spacing and minimum pumping rate for a well pair: (1) centered on the downgradient tip of the plume (best centered), and (2) anywhere along the downgradient transect (best overall). Results suggest that low‐energy well pairs are an effective means for containing and removing some contaminant plumes, and best‐performing configurations are generally not centered on the downgradient tip of the initial contaminant plume. ©2015 Wiley Periodicals, Inc.