Tài liệu miễn phí Hoá dầu
Download Tài liệu học tập miễn phí Hoá dầu
NANOWIRES - RECENT ADVANCES_1
Tham khảo sách 'nanowires - recent advances_1', kỹ thuật - công nghệ, hoá học - dầu khí phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả
8/30/2018 2:01:24 AM +00:00
ALUMINIUM ALLOYS NEW TRENDS IN FABRICATION AND APPLICATIONS_2
Aluminium alloys have undergone a dramatic transformation in areas of extrusion, machining, welding, heat treatment, structural changes, created by ultra fine particles and enhanced corrosion resistance. Hence, these alloys have made rapid gains in European automotive and space industry. These developments have been described by experts in the book with new data and attractive graphics. The effect of processing parameters, including welding and deep rolling on their performance have been highlighted to alleviate the concerns of manufacturers and designers for new applications. The novel role of aluminum alloys in photovoltaic cells and concentrated solar power has been comprehensively described in...
8/30/2018 2:01:23 AM +00:00
HIGH PERFORMANCE POLYMERS – POLYIMIDES BASED – FROM CHEMISTRY TO APPLICATIONS
The feature of polyimides and other heterocyclic polymers are now well-established and used for long term temperature durability in the range of 250 - 350'C. This book will review synthesis, mechanisms, ultimate properties, physico-chemical properties, processing and applications of such high performance materials needed in advanced technologies. It presents interdisciplinary papers on the state of knowledge of each topic under consideration through a combination of overviews and original unpublished research. The volume contains eleven chapters divided into three sections: Chemistry; Chemical and Physical Properties; and Applications....
8/30/2018 2:01:23 AM +00:00
IDENTIFICATION OF AN UNKNOWN ORGANIC COMPOUND: Classification Tests
Certifying organisations inspect operators annually to ensure they comply with the National Standard. They are also authorised to issue organic produce certificates on behalf of the Australian Government. An AQIS-approved organic certifying organisation must undergo an annual audit of its documented system. AQIS also audits the inspection system of certifying organisations at various organic farms, processors, wholesalers and exporters. AQIS and industry has established Administrative Arrangements outlining the administrative policies and operational procedures for certifying organisations. These arrangements cover requirements including objectivity and integrity, structure and training, sanctions and penalties, inspection and certification and export requirements....
8/30/2018 2:01:21 AM +00:00
The Organic Products in the Green Marketing Laboratory
Ian and Jane Campbell of Barambah Organics near Murgon in Queensland produce, process and market certified organic milk. Their movement into organic production was born from a long family interest in sustainable agriculture and the need to create a point of difference for their products. “Customers are often surprised by the unique taste of our milk. It comes from a balanced and healthy diet for the cows on our chemical-free broadacre pastures,” said Ian. Soil health and weed control are important considerations and are carefully managed with compost manures and lime. Being organic also means that cows are treated only with natural remedies such as homeopathy and minerals...
8/30/2018 2:01:21 AM +00:00
ORGANIC CHEMICALS AND POLYMERS
Ian and Jane also became involved in processing and marketing their own products about five years ago. They found that there is a lot to learn about running a paddock- to-plate supply chain, including hiring staff and building strategic partnerships. Employment problems, particularly recruiting and training the right people, proved to be a significant issue for the business. Barambah Organics’ much larger involvement across the supply chain meant the business required a new range of skills and people with expertise in milk processing and financial management, as well as traditional farm management. ...
8/30/2018 2:01:21 AM +00:00
Organic Crop Production
Data on organic production was obtained from two sources. As a first step data was gathered from organic certifying organisations. The National Association for Sustainable Agriculture Australia, Biological Farmers of Australia/Australian Certified Organic, Tasmanian Organic- Dynamic Producers and Safe Food Production Queensland provided data. The data gathered from certifiers has a number of limitations. Firstly, only the certifying organisations that charge a levy based on sales were able to supply data on farm production. The data that was provided is not consistent and often incomplete. In addition, the data does not take into account any products not sold under a certifying organisation’s label. Any producers who were...
8/30/2018 2:01:21 AM +00:00
ORGANIC FOODS CONTAIN HIGHER LEVELS OF CERTAIN NUTRIENTS, LOWER LEVELS OF PESTICIDES, AND MAY PROVIDE HEALTH BENEFITS FOR THE CONSUMER
A detailed account of the field history, farm maps, crop rotations, and a comprehensive plan of operation for following organic protocols need to be incorporated into the plan. All fields, greenhouses, storage areas, warehouses, and processing facilities used in organic production must be discussed in the OSP. Growers with split operations (organic and conventional production on the same farm) need to include information on how they plan to prevent commingling of the two systems. They must also identify how equipment used in both organic and conventional production will be cleaned and managed prior to use on organic...
8/30/2018 2:01:21 AM +00:00
Marketing of Indian Organic Products: Status, Issues, and Prospects
Globally, the market for organic food products doubled between 2002 and 2007, to more than $46 billion (USD) [2,3], with North America representing one of the fastest growing markets in the sector. Canadian sales of organic products exceeded an estimated $1 billion in 2006 [4]. In 2009, Canada enacted new federal regulations for organic production, requiring mandatory certification to a revised national standard for all products represented as organic in inter-provincial or international trade. These regulations replace a previously voluntary certification process and address issues of regulatory equivalency between major trading partners. ...
8/30/2018 2:01:21 AM +00:00
Groundwater contamination by organic chemicals in industrializing countries: the unseen threat
The number of certified organic farms in Canada has also been on the rise, increasing 60% between 2001 and 2006. In 2006, there were about 3,500 certified organic farms, representing 1.5% of all farms in Canada [6]. Nearly half (45%) of these farms are situated in the Prairie Provinces, with Saskatchewan accounting for about one-third of the nationwide total. Like their conventional counterparts, most (95%) organic producers on the Prairies are engaged in the production of hay or field crops, primarily wheat and barley, but also including a variety of other grains, pulses....
8/30/2018 2:01:21 AM +00:00
PATHWAYS OF ORGANIC CHEMICAL CONTAMINATION IN ECOSYSTEMS
Despite the steady growth in the organic sector in recent years, it remains a fledgling research area, particularly in Western Canada. Most of the information on the benefits and impacts of organic agriculture is based on research from Europe, and there has been comparatively little research focused on the contribution of organic production to sustainable agriculture in the Canadian context. While many recognize the intuitive appeal of organic agriculture as a low-input, holistic alternative to conventional production systems, serious questions remain about its long-term sustainability. ...
8/30/2018 2:01:21 AM +00:00
ORGANIC MEAT: MARKET DEVELOPMENT AND CONSUMER WILLINGNESS TO PAY
In the Canadian Prairies, there is particular concern about the depletion of soil phosphorous from organic grain production [7], and the long-term impacts of tillage practices employed by organic producers [8]. Grain yields under organic management are, on average, lower than under conventional management, and it has been suggested that the yield deficit is more severe on the Canadian Prairies than some other regions [9]. Even where yields are similar, reliance on rotational strategies over synthetic fertilizers to maintain soil nutrients may place a further constraint on the overall productivity of organic cash crops [10]. Conversely, some studies...
8/30/2018 2:01:21 AM +00:00
ORGANIC-APPROVED PESTICIDES
These guidelines address methods for: (1) handling of samples as intact soil cores; (2) preserving samples; (3) storing samples in hermetically sealed containers; and (4) minimizing analyte losses due to direct volatilization (both in the field and the laboratory) and biodegradation. Region 9 believes that following these guidelines is an important part of ensuring that accurate concentrations of VOCs are measured. Therefore, the procedures by which data are generated for or by Region 9 should follow project and/or program specific methods for field sample collection and laboratory sample handling which adhere to these guidelines. Specific procedures should...
8/30/2018 2:01:21 AM +00:00
DNA-Templated Organic Synthesis: Natures Strategy for Controlling Chemical ReactivityApplied to Synthetic Molecules**
EPA Region 9 has developed technical guidelines to help ensure that sampling and analyzing for Volatile Organic Compounds (VOCs) in soil and solid matrices are conducted in a manner that achieves accurate, technically defensible data. Region 9’s guidelines, which are intended to apply whenever VOC sampling in and analysis of soil and solid matrices are conducted, are consistent with United States Environmental Protection Agency (USEPA) Office of Solid Waste test methods. These are included as part of a compendium of over 200 documents in “Test Methods for Evaluating Solid Wastes and Physical/Chemical Methods, SW-846” (hereafter “SW-846”), which...
8/30/2018 2:01:21 AM +00:00
TECHNIQUES FOR THE ANALYSIS OF ORGANIC CHEMECALS BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY (ICP-MS)
To help ensure accurate measurements, Region 9 recommends that these guidelines be followed whenever VOCs in soil or other solid matrices are sampled and analyzed. These guidelines address methods for: (1) handling of samples as intact soil cores; (2) preserving samples; (3) storing samples in hermetically sealed containers; and (4) minimizing analyte losses due to direct volatilization (both in the field and the laboratory) and biodegradation. Region 9 believes that following these guidelines is a scientifically important part of ensuring that accurate concentrations of VOCs are measured. Therefore, the procedures by which data are generated for or...
8/30/2018 2:01:21 AM +00:00
ELEGANT ANALYTICAL CHEMISTRY APPLIED TO ENVIRONMENTAL PROBLEMS - A PRACTICAL SYMPOSIUM
However, these guidelines do not address the impact of drilling techniques on the collection of a representative VOC sample. Therefore, site/program QAPPs and SAPs should address the impact of all collection techniques on sample integrity and select those appropriate for the project data quality objectives (DQOs). Potential VOC losses due to drilling techniques include, but are not limited to: sample compression and loss of pore space; introduction of air into the sample matrix; mechanical heat introduced in the drilling process; and volatilization from prolonged periods in a non- hermetically sealed sampling apparatus. ...
8/30/2018 2:01:21 AM +00:00
Atmospheric volatile organic compound measurements during the Pittsburgh Air Quality Study: Results, interpretation, and quantification of primary and secondary contributions
Further, solid matrices that are not amenable to the use of a coring technique should be collected in such a way as to preserve their integrity. Transferring of these solids with spatulas or similar devices into sampling containers is discouraged as this disrupts the sample pore spaces and greatly increases the sample surface area available for volatilization. For soil piles, fresh (unexposed), soil at an adequate depth (representative of concentrations from the interior of the pile) should be sampled. Gravel or concrete samples may need to be manually transferred into VOC sampling containers quickly and in a condition and...
8/30/2018 2:01:21 AM +00:00
Detection of Pseudomonas aeruginosa in sputum headspace through volatile organic compound analysis
Soil samples stored in sealed vials have been shown to undergo significant biodegradation over time periods greater than 48 hours. Holding time guidelines for VOCs are given in SW846, Method 5035A, Appendix A, Table A.1 “Recommended VOC Sample Preservation Techniques and Holding Times.” The holding time for preserved soil samples should be interpreted as 14 days from the time of sample collection (stored at 4±2o C). Due to potential biodegradation, samples stored in sealed containers, but not chemically preserved, should not be stored for more than 48 hours prior to analysis or chemical preservation. ...
8/30/2018 2:01:21 AM +00:00
Chemical contamination at e-waste recycling and disposal sites in Accra and Korforidua, Ghana
Care should be taken in choosing preservatives. For example, Method 5035 notes that, “Soil samples that contain carbonate minerals (either from natural sources or applied as an amendment) may effervesce upon contact with the acidic preservative solution in the low concentration sample vial.” Therefore, calcareous soils that effervesce on contact with the preservative solution, which is intended for low-level samples, should be preserved using an alternative technique. As an alternative to chemical preservatives, several studies have shown that freezing of unpreserved soils, at -7 o C or less, is an effective means of slowing the biodegradation process. ...
8/30/2018 2:01:21 AM +00:00
THE EFFECTS OF THREE ORGANIC CHEMICALS ON THE UPPER THERMAL TOLERANCES OF FOUR FRESHWATER FISHES
Addition of Surrogates and Matrix Spiking Compounds in the Field: It is best to add analytical surrogate and matrix spiking compounds into soils prior to sample extraction, using water or a solvent. Method 5035A does not incorporate the addition of these compounds prior to extraction in the field. Because this is an important control check on the analytical process, it may be appropriate to incorporate a procedure which adds surrogate and/or matrix spiking compounds prior to extraction for some project/program DQOs. This procedure should be implemented in consultation with the analytical laboratory. Soil Gas: These guidelines are not...
8/30/2018 2:01:21 AM +00:00
FOR ORGANIC CHEMICALS IN WATER (latest version 04/01)
In some countries and regions regulations have been introduced with the aim of restricting the use of hazardous substances in these products, and the management of e-waste at the products end of life. However, no such regulations exist in many of the countries in which where products are manufactured, used and disposed of. Furthermore, even where they apply, regulations do not control all hazardous chemicals and materials that are used in newly manufactured products, nor fully address the management of e- waste. Even in the EU, where some of the more stringent regulations apply, as much as 75% of generated e-waste is unaccounted for. There is evidence...
8/30/2018 2:01:21 AM +00:00
USEPA REGION 9 TECHNICAL GUIDELINES FOR ACCURATELY DETERMINING VOLATILE ORGANIC COMPOUND (VOC) CONCENTRATIONS IN SOIL AND SOLID MATRICES
This study, the first to investigate workplace contamination in areas in Ghana where e-waste recycling and disposal is carried out, focussed on the main centre for this type of work, at the Agbogbloshie scrap market in Ghana’s capital, Accra. One of the numerous similar, though far smaller, operations that take place throughout Ghana was also investigated, at the location of a scrap dealer in Korforidua, a smaller city to the north of Accra. At these workshops, e-waste is recycled in a crude way, primarily involving manual disassembly and open burning to isolate copper from plastics. Much of the work is carried out by children, commonly...
8/30/2018 2:01:21 AM +00:00
Trichloroethylene (TCE): TEACH Chemical Summary
Severe chemical contamination was found in ash contaminated soil samples from open burning sites at both Agbogbloshie and Korforidua, as well as in sediment from a shallow lagoon at the Agbogbloshie site. Most samples contained numerous toxic and persistent organic chemical pollutants, as well as very high levels of many toxic metals, the majority of which are either known to be used in electronic devices, or are likely to be formed during the open- burning of materials used in such devices. The nature and extent of chemical contamination found at these sites in Ghana were similar to those previously reported for e-waste open burning sites in...
8/30/2018 2:01:21 AM +00:00
Synthesis and Application of Nanosize Semiconductors for Photoxidation of Toxic Organic Chemicals
At the open burning sites, some metals were present at concentrations over one hundred times typical background levels for soils, including lead, a highly toxic metal. High levels of other toxic metals, including cadmium and antimony, were also present. Numerous classes of organic chemicals were also present in one or more of the samples, including many halogenated (chlorinated or brominated) chemicals. Many of the compounds identified are intentionally used in electronic devices. These included phthalates, widely used as plasticisers in flexible plastics such as PVC, polybrominated diphenyl ethers (PBDEs) and triphenyl phosphate (TPP) both used as flame retardants, and polychlorinated biphenyls (PCBs) , long banned from...
8/30/2018 2:01:21 AM +00:00
Measurement of Organic Chemical Refractive Indexes Using an Optical Time-Domain Reflectometer
Two samples were also analysed for polychlorinated dioxins and furans (PCDD/Fs), a class of chemical that can be formed during the combustion of materials present in e-waste. Soil from an open burning site was moderately contaminated, while sediment from the Agbogbloshie lagoon contained a very high level of these highly toxic, highly persistent and bioaccumulative chemicals, at a level just below the threshold defined as being indicative of serious contamination for sediments in the Netherlands. Though this study did not attempt to quantify damage caused to the environment or human health, the results do indicate that the exposure of workers and bystanders to hazardous chemicals may be substantial. In...
8/30/2018 2:01:21 AM +00:00
The Sustainability of Organic Grain Production on the Canadian Prairies—A Review
Demand for organically produced food products is increasing rapidly in North America, driven by a perception that organic agriculture results in fewer negative environmental impacts and yields greater benefits for human health than conventional systems. Despite the increasing interest in organic grain production on the Canadian Prairies, a number of challenges remain to be addressed to ensure its long-term sustainability. In this review, we summarize Western Canadian research into organic crop production and evaluate its agronomic, environmental, and economic sustainability. ...
8/30/2018 2:01:21 AM +00:00
Optimal Time for Collecting Volatile Organic Chemical Samples from Slowly Recovering Wells
Worldwide consumption of organic products has experienced tremendous growth, often surpassing the U.S. figures of 20 percent annual gain. Much of the increase in worldwide consumption has been fueled by consumers’ demand for GMO-free products. Because GMOs are disallowed in organic production and processing, organic products auto- matically are designated as GMO-free at the marketplace. European consumers have led the demand for organic products, particularly in coun- tries such as the Netherlands, Italy, and Austria. Two percent of all German farmland, four percent of Italian farmland, and 10 percent of Austrian farm- land is managed organically. Prince Charles of England has developed a model organic farm and has established a system of government support for farmers...
8/30/2018 2:01:20 AM +00:00
PURIFICATION OF ORGANIC CHEMICALS
This module is the eighth in a series of Extension materials designed to provide Extension agents, Certified Crop Advisers (CCAs), consultants, and producers with pertinent information on nutrient management issues. To make the learning ‘active,’ and to provide credits to Certified Crop Advisers, a quiz accompanies this module. In addition, realizing that there are many other good information sources, including previously developed Extension materials, books, web sites, and professionals in the field, we have provided a list of additional resources and contacts for those wanting more in-depth information about soil pH and organic matter. This module covers the following Rocky...
8/30/2018 2:01:20 AM +00:00
APPENDIX A TO PART 136 METHODS FOR ORGANIC CHEMICAL ANALYSIS OF MUNICIPAL, INDUSTRIAL WASTEWATER
In modifying soil pH, the addition of amendments, fertilizers, tillage practices, soil organic matter levels, and drainage should all be considered. A common amendment used to acidify alkaline soils is sulfur (S) (Slaton et al., 2001). Elemental sulfur (S0 ) is oxidized by microbes to produce sulfate (SO4 2- ) and H+, causing a lower pH. Ferrous sulfate (FeSO4 ) and aluminum sulfate (Al 2 (SO4 )3 ) can also be used to lower pH, not due to SO4 , but because of the addition of acidic cations (Fe2+, Al 3+) (see Q & A #1). Application rates for these amendments will vary depending upon product properties (particle size, oxidation...
8/30/2018 2:01:20 AM +00:00
Topological insulator Bi2Te3 films synthesized by metal organic chemical
Using chemical ionization mass spectrometry and photo- acoustic spectroscopy, we analysed the evolution of vola- tile organic compounds (VOCs) and other trace gases dur- ing an approximately one-week measurement period each in a pigsty and a sheep shed at the Federal Agricultural Research Centre (FAL) in Mariensee, Germany. When ac- tivities in the sheep shed were most intense during feeding hours and manure removal, concentration surges of VOCs were observed, which strongly correlated with methane and ammonia levels. Immediately after this disturbance, especially the manure removal, which lasted for about 30 minutes, the short-term concentration spikes decayed exponentially as a result of dilution of...
8/30/2018 2:01:20 AM +00:00