低温热解玉米秸秆制备生物炭的存储性能研究

针对玉米秸秆高含水量、易吸水影响燃料燃烧及存储性能等问题,采用低温连续热解玉米秸秆工艺制备220、240、250和270℃的生物炭,并对接触角、疏水性能和抗真菌腐蚀性能进行了表征,结果表明,低温炭化工艺能减少亲水性含氧基团,降低其含水率和吸水性能;生物炭的疏水性能随着炭化温度的升高而增强;240和270℃的生物炭表现出较好的抗微生物霉变性能。

洞库防水防潮的处理

上世纪60年代建的洞库由于地质结构,断裂层、毛洞充填的不饱满,存在不同程度的漏水、渗水,洞内外有温差,产生凝结水,使仓储物质变质的外理。本文对此论述整改措施。

Biomass Carbon Sequestration by Planted Forests in China

The planted forest area and carbon sequestration have increased significantly in China,because of large-scale reforestation and afforestation in the past decades.In this study,we developed an age-based volume-to-biomass method to estimate the carbon storage by planted forests in China in the period of 1973-2003 based on the data from 1209 field plots and national forest inventories.The results show that the total carbon storage of planted forests was 0.7743 Pg C in 1999-2003,increased by 3.08 times since the early 1970s.The carbon density of planted forests varied from 10.6594 Mg/ha to 23.9760 Mg/ha and increased by 13.3166 Mg/ha from 1973-1976 to 1999-2003.Since the early 1970s,the planted forests in China have been always a carbon sink,and the annual rate of carbon sequestration was 0.0217 Pg C/yr.The carbon storage and densities of planted forests varied greatly in space and time.The carbon storage of Middle South China was in the lead in all regions,which accounted for 23%-36% of national carbon storage.While higher C densities (from 17.79 Mg/ha to 26.05 Mg/ha) were usually found in Northeast China.The planted forests in China potentially have a high carbon sequestration since a large part of them are becoming mature and afforestation continues to grow.

Effect of Carbonation on Microbiologic Parameters of Refrigerated Bovine Raw Milk

This study evaluated the effect of carbon dioxide addition on microbiological quality during refrigerated storage of raw milk collected in Curitiba city, Brazil. A three factor-two level full factorial design was used to investigate the effect of the pH （5.8-6.4）, storage time （0-10 days） and storage temperature （5-10 ℃）, on the responses, namely, mesophiles, psychrotrophs, lipolytic psychrotrophs and proteolytic psychrotrophs counts. Results showed that increase in pH and storage time had significant effect on the microbial count. No significant effect of storage temperature was observed for all the microorganisms studied. All responses were well predicted by selected mathematical models, as denoted by coefficient of determination above 0.95.

Cereal Storage Techniques： A Review

Cereal grains are stored to preserve the product from storing to consuming without any quality loss. The choice of the most suitable and economical store has great importance on storage period of cereals under consideration of climate conditions, types of grain and transportation facility. The aim of present study was to give information about different cereal storage methods and discuss the most preferable technique for stock keepers. There are five main storage methods for the cereals, i.e., bulk storage, storage in underground pit, storage in bags, storage in sheds and storage in silos. Each has many advantages and disadvantages. Grains are usually preserved as bulk stack in horizontal stores. Nowadays, the storage underground is not preferred in cereal industry. For long-term storage period, cereals are unfavorable when stored as bulk in bags. Location, moisture content and sufficient ventilation are important factors for cereals stored in sheds. The most preferred storage technique in plants is to keep the products in silos. Steel and galvanized silos are the most common ones when compared with the others. In recent years, convention of storage techniques for grains has been advanced with the innovations, such as aeration, refrigerated storage, modified atmospheric storage and hermetic storage systems.

Three-Dimensional Heat Transfer Analysis for A Thermal Energy Storage Canister

High temperature latent thermal storage is one of the critical techniques for a solar dynamic power system. This paper presents results from heat transfer analysis of a phase change salt containment canister A three-dimensional analysis program is developed to model heat transfer in a PCM canister. Analysis include effects of asymmetric circumference heat flux, conduction in canister walls, liquid PCM and solid PCM, void volume change and void location, and conduction and radiation across PCM vapor void. The PCM phase change process is modeled using the enthalpy method and the simulation results are compared with those of other two- dimensional investigations. It’s shown that there are large difference with two-dimensional analysis, therefore the three-dimensional model is necessary for system design of high temperature latent thermal storage.

Removal of toxic metal ions using chitosan coated carbon nanotube composites for supercapacitors

Environmental pollution and energy crisis are two major global challenges to human beings.Recovering energy from wastewater is considered to be one of the effective approaches to address these two issues synchronously.As the main pollutants in wastewater,toxic heavy metal ions are the potential candidates for energy storage devices with pseudocapacitive behaviors.In this study,toxic metal ions of Cr(VI)and Cu(II)are removed efficiently by chitosan coated oxygen-containing functional carbon nanotubes,and the corresponding equilibrium adsorption capacity is 142.1 and 123.7 mg g^(-1).Followed by carbonization of metal ions-adsorbed adsorbents,Cu-and Cr N-loaded carbon composites can be obtained.Electrochemical measurements show that the supercapacitor electrodes based on Cu-and Cr N-loaded carbon composites have specific capacitance of 144.9 and 114.9 F g^(-1)at2 m V s^(-1),with superior electrochemical properties to pure chitosan coated carbon nanotubes after carbonization.This work demonstrates a new strategy for the resource-utilization of other heavy metal ions for energy devices,and also provides a new way to turn environmental pollutants into clean energy.

Biomass-derived carbon materials with structural diversities and their applications in energy storage

Currently, carbon materials, such as graphene,carbon nanotubes, activated carbon, porous carbon, have been successfully applied in energy storage area by taking advantage of their structural and functional diversity. However, the development of advanced science and technology has spurred demands for green and sustainable energy storage materials.Biomass-derived carbon, as a type of electrode materials, has attracted much attention because of its structural diversities,adjustable physical/chemical properties, environmental friendliness and considerable economic value. Because the nature contributes the biomass with bizarre micro structures,the biomass-derived carbon materials also show naturally structural diversities, such as OD spherical, 1D fibrous, 2D lamellar and 3D spatial structures. In this review, the structure design of biomass-derived carbon materials for energy storage is presented. The effects of structural diversity, porosity and surface heteroatom doping of biomass-derived carbon materials in supercapacitors, lithium-ion batteries and sodium-ion batteries are discussed in detail. In addition, the new trends and challenges in biomass-derived carbon materials have also been proposed for further rational design of biomass-derived carbon materials for energy storage.