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41.
Cattle (Bos taurus) producers can replace a part of the traditional diet of barley (Hordeum vulgare L.) grain/silage with sunflower (Helianthus annus L.) seeds or canola meal (Brassica napus L.)/oil to enhance conjugated linoleic acids (CLA) content in milk and meat for its positive health benefits. The objective of this study is to investigate the effects of feeding sunflower or canola to finishing steers on cattle manure chemical properties and volatile fatty acid (VFA) content. The control diet contained 84% rolled barley and 15% barley silage, which provided only 2.6% lipid. The other six treatments had 6.6 to 8.6% lipid delivered from sources such as hay, sunflower seed (SS), canola meal/oil, and SS forage pellets. Manure samples (a mixture of cattle urine, feces, and woodchip bedding materials) were collected and analyzed after cattle had been on these diets for 113 d. The dietary source and level of lipid had no effect on organic N and nitrate N content in manure, but significantly affected ammonia N and VFA. Inclusion of SS forage pellets, hay, or canola meal/oil in cattle diets had no significant impact on manure characteristics, but SS significantly reduced the pH and increased propionic, isobutyric, and isovaleric content. In addition, N loss after excretion (mainly from urine N) increases with the pH and N levels in both feed and manure. The combination of SS with barley silage resulted in a lower VFA and NH3 content in manure and should be a more attractive option. To better manage N nutrient cycles and reduce NH3 related odor problems, feed and manure pH should be one of the factors to consider when determining feed mix rations.  相似文献   
42.
Environmental Science and Pollution Research - The use of sewage water as an irrigation source can be beneficial in agricultural practices, however, it may result in human health risks due to the...  相似文献   
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44.
Tea in Darjeeling foothills and terai are grown conventionally, with application of chemical fertilizers and pesticides, as well as organically without these inputs. Ground level arthropod community was collected from the above two types of tea plots using pitfall traps. Catches from these environments showed variation in the arthropod faunal structure with numerically and taxonomically greater abundance in the organic than that of the conventional plot. Coleopterans were more diverse with largest number of families and Recognizable Taxonomic Units (or morphospecies) in the organic tea plot. The diversity and similarity indices for coleopterans were comparable, in organic and conventional tea plots at species and family levels. The close relationship of the indices suggested that diversity study at family level could be used as surrogate for species level diversity; thus alleviating the laborious and expertise job of taxonomic identification of arthropod species. Faunal diversity study at ground level gave the clue that soil of the organic plantation was healthier than that of the conventional tea plot.  相似文献   
45.
防电磁波辐射的功能性服装   总被引:4,自引:0,他引:4  
电磁波辐射已成为危害人类健康的第四大污染源,如何进行屏蔽是人们日益关注的问题,本文介绍了防电磁波辐射服装的功能及特点,提出了屏蔽服装今后的发展方向.  相似文献   
46.
Solvent extraction is used to reduce lead concentrations from millpond wastewater solids, a type of foundry process waste. Toluene and toluene mixed with di-(2-ethyl-hexyl) phosphoric acid (HDEHP) have been tried as leaching solvents. Toluene is ineffective as a solvent in extracting lead, but the toluene-HDEHP mixture effectively removes lead from solid foundry waste. The effects of the HDEHP concentration, the contact time, and the amount of solvent used on lead extraction have been investigated. The mass transfer process is rapid: contact time of 1/2 hour has been found to be sufficient to accomplish the leaching process. The concentration of HDEHP significantly impacts lead removal. The optimum concentration of HDEHP is determined to range from 0.05 to 0.1 mol/l. The Toxicity Characteristic Leaching Procedure (TCLP) test of the treated samples gives leachable lead in much lower quantities than those found in the untreated samples. Thus the solvent extraction process appears to be an effective method to significantly reduce the lead content of millpond wastewater solids.  相似文献   
47.
Background. Playing guitar can cause adoption of asymmetric postures and affect the shoulder's stability. Objective. To assess the presence of scapular dysfunction in professional guitar players. Method. A lateral scapular slide test was performed at the level of the spine of the scapula and at the inferior angle of the scapula in 20 professional guitar players (age: 18–40 years) and was compared with 20 age-matched non-players at angles of 0°, 45° and 90° of shoulder abduction with both limbs loaded with 0.5-kg weights. Analysis was done by unpaired t test. Results. Scapular dysfunction in guitar players was seen in the form of asymmetric scapula at rest in 25% and dyskinetic scapula in 20% of players. 100% of non-players had normal scapular positioning. Comparison at the level of the spine of the scapula showed no significant difference (p?>?0.05), but the inferior angle showed a significant difference at 0° (1.37?cm), 45° (1.93?cm) and 90° (2.15?cm) which was more in the player's category (p?Conclusion. There exists a marked dysfunction of scapular stabilizers in professional guitar players at the level of the inferior angle of the scapula.  相似文献   
48.
实验室加速试验与自然暴露试验差异性研究   总被引:2,自引:2,他引:0  
对同一批次涂层体系试验样品分别进行实验室加速试验和自然环境暴露试验,对不同试验状态考核检测结果进行分析,重点从试验时间、试验腐蚀环境严酷度对2种试验方法与检测结果的差异性进行了分析,对实验室加速试验检测考核涂层体系存在的主要问题和改进思路进行了分析探讨.  相似文献   
49.
Sulfamethoxypyridazine(SMP) is one of the commonly used sulfonamide antibiotics(SAs).SAs are mainly studied to undergo triplet-sensitized photodegradation in water under natural sunlight with other coexisting aquatic environmental organic pollutants.In this work,SMP was selected as a representative of SAs.We studied the mechanisms of triplet-sensitized photodegradation of SMP and the influence of selected dissolved inorganic matter,i.e.,anions(Br~-,Cl~-,and NO~-_3) and cations ions(Ca~(2+),Mg~(2+),and Zn~(2+)) on SMP photodegradation mechanism by quantum chemical methods.In addition,the degradation mechanisms of SMP by hydroxyl radical(OH·) were also investigated.The creation of SO_2 extrusion product was accessed with two different energy pathways(pathway-1 and pathway-2) by following two steps(step-I and step-II) in the tripletsensitized photodegradation of SMP.Due to low activation energy,the pathway-1 was considered as the main pathway to obtain SO_2 extrusion product.Step-II of pathway-1 was measured to be the rate-limiting step(RLS) of SMP photodegradation mechanism and the effect of the selected anions and cations was estimated for this step.All selected anions and cations promoted photodegradation of SMP by dropping the activation energy of pathway-1.The estimated low activation energies of different degradation pathways of SMP with OH·radical indicate that OH·radical is a very powerful oxidizing agent for SMP degradation via attack through benzene derivative and pyridazine derivative ring.  相似文献   
50.
We investigated selected chlorinated pollutants (β-HCH, γ-HCH, DDDs, DDEs, o,p′-DDT, p,p′-DDT, heptachlor, aldrin, dieldrin, and endrin) in the Lahore and the Sialkot districts of Pakistan, using eggs of cattle egret (Bubulcus ibis) collected during May and June 2007. The pollutant with highest level and frequency was ΣDDT, followed by β-HCH, γ-HCH, heptachlor, aldrin, dieldrin, and endrin in descending order. The concentration(s) were significantly higher in Sialkot heronry for all the pollutants (except p,p′-DDT) than in Lahore. The values for DDTs, β-HCH, γ-HCH, and heptachlor were significantly higher (p < 0.05) in the egg(s) than in sediment(s) and in the chicks’ diet, due to biomagnification. Among DDTs analogues, p,p′-DDD was the major contaminant with >60 % of total DDT burden, reflecting the widespread aged as well as recent use of DDT as well as anaerobic degradation (DDD/DDE > 1 in many cases) in the nearby paddy soils. In few samples, p,p′-DDT/(DDD + DDE) > 0.5 suggested the recent emission patterns from surrounding contaminated areas of demolished DDT units and obsolete pesticide stores. The higher levels of HCHs (i.e., β-HCH) in the samples collected from Sialkot indicate exposure from long-term agricultural use. Overall, concentrations of all studied POPs were less than the threshold levels known to affect reproduction. Nevertheless, total DDTs and/or HCHs burdens in some eggs contained concentrations of greater than what would educe adverse effects on birds. This is among few studies on OCPs exposure to avian species, which provide the evidence of Pakistan’s contribution toward the Global POPs emission.  相似文献   
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