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181.
ZnS对可溶性染料的光催化降解研究   总被引:10,自引:0,他引:10  
以ZnS为光催化剂,对6种可溶性染料进行了光催化降解研究,结果表明,ZnS对染料溶液的脱色效果非常显著,光催化反应属动力学一级反应。  相似文献   
182.
不同锌源及其水平对桃源鸡血清抗氧化指标的影响   总被引:1,自引:0,他引:1  
[目的]探究不同锌源、锌水平对桃源鸡血清抗氧化指标的影响。[方法]选用420只桃源鸡,采用2因素3水平完全随机试验设计,2种锌源分别为羟基蛋氨酸锌、氧化锌,添加水平分别为30、60、90mg/kg,将桃源鸡随机分为7个处理组,每个处理组设3个重复,每个重复20只鸡,分3~48、48~93日龄2个阶段饲养,每个试验期结束时进行桃源鸡血清抗氧化指标测定试验。[结果]试验前期,锌的添加及不同添加水平时桃源鸡血清SOD活性、血清MDA含量在0.05水平上差异不显著,随着锌水平的添加同一锌源内血清SOD活性呈上升趋势;试验后期,锌源添加水平为90 mg/kg时血清SOD活性在0.05水平上显著高于基础日粮组,氧化锌添加水平为90mg/kg时血清MDA含量在0.05水平上显著低于基础组,不同锌源、锌水平间血清SOD活性差异不显著,血清MDA含量呈下降趋势。[结论]锌源的添加能提高桃源鸡血清中SOD酶活性,降低血清中MDA含量,减轻自由基的损伤,从而提高机体的抗氧化能力,在高温条件下更加明显;但羟基蛋氨酸锌和氧化锌两者间对桃源鸡血清中SOD活性和MDA含量的影响变化规律还有待进一步研究。  相似文献   
183.
This study was conducted to assess the effects of different dose levels of zinc oxide (ZnO) combined with probiotics complex supplementation on the growth, performance, nutrient digestibility, faecal lactobacillus and Enterobacteria counts, noxious gas emissions and faecal score of weaned piglets. A total of 180 crossbred weaning pigs ([Yorkshire × Landrace] × Duroc; 6.61 ± 1.29 kg [mean ± SE]; 28 days old) were used in a 42-day trial. All pigs were randomly allotted to 1 of 4 treatment diets based on initial BW and sex (9 replicate pens/treatment; 2 gilts and 3 barrows/pen). Dietary treatment groups were as follows: CON, basal diet +ZnO 3,000 ppm; BZS, basal diet +ZnO 2,100 ppm +0.1% SynerZymeF10; BZS1, basal diet +ZnO 1,200 ppm +0.1% SynerZymeF10; BZS2, basal diet +ZnO 300 ppm +0.1% SynerZymeF10. During the phase 3, decreasing the ZnO concentration led to a linear reduction in ADG (p = 0.044), and the ADG was lower (p < 0.05) in BZS2 compared with CON treatment during the whole experimental period. The effects of dietary ZnO with probiotics complex were not detected (p > 0.05) on nutrient digestibility, Lactobacillus and E. coli counts, faecal gas emissions and faecal scores. In conclusion, the diet supplementation of ZnO (1,200 ppm) with probiotics complex has been shown to have comparable efficacy to ZnO (3,000 ppm) diet on growth performance, nutrient digestibility, faecal microbiota, noxious gas emissions and faecal score of weaning pigs.  相似文献   
184.
锌对苦瓜叶片内源激素与氮代谢及产量的影响研究   总被引:5,自引:0,他引:5  
田间试验研究不同Zn肥施用量对苦瓜产量、叶片内源激素与N代谢的影响结果表明 ,土壤缺Zn时施用硫酸锌 30~ 4 5kg/hm2 可显著提高苦瓜产量 ,增幅 16 .2 1%~ 17.16 %。施Zn可提高叶片吲哚乙酸、赤霉素、蛋白质和核酸含量及硝酸还原酶活性 ,降低叶片色氨酸、游离氨基酸和NO3 - N含量及RNase活性。叶片蛋白质与核酸、硝酸还原酶呈极显著正相关 ,而与游离氨基酸、NO3 - N含量和RNase活性呈极显著负相关 ;叶片色氨酸含量与吲哚乙酸和赤霉素含量 ,核酸含量与RNase活性均呈极显著负相关。  相似文献   
185.
湖北江汉平原农田生态系统麦-稻、稻-稻、油菜-大豆、油菜-花生、小麦-芝麻、小麦-棉花、青椒-大白菜、萝卜-茄子等8种种植模式农田Zn素的循环研究表明,土壤Zn的输入途径和输入量顺序菜田和水田为有机肥>降雨>归还>灌溉>种子(种苗),旱地为降雨>有机肥>归还>灌溉>种子(种苗),输出途径作物收获占96%~97.6%,平均96.7%,农田Zn流失和淋溶损失相对较少。该区域菜田Zn素盈余较多,稻田一盈一亏,旱田施有机肥和施Zn肥处理Zn有盈余,不施Zn肥和有机肥2种模式出现亏缺。  相似文献   
186.
In this paper, the effects of earthworms on the growth and Zn uptake of ryegrass and Indian mustard in artificially Zn-contaminated soils were studied. Earthworm inoculation increased plant shoot biomass by 29–83% for ryegrass and by 11–42% for Indian mustard, respectively, as compared to the treatments without earthworms, while the roots’ biomass of both plants were increased much more than their corresponding shoots. Earthworms also increased shoot Zn concentrations in both ryegrass and Indian mustard, although the increases in ryegrass did not show significant difference. Except for soil without Zn contamination, the Zn contents of both ryegrass and Indian mustard roots were significantly increased by earthworm addition. Generally, Zn contents of roots were relatively higher than those of shoots for both plants, which were independent of earthworms inoculation. Earthworm increased soil bioavailable metal (diethylenetriamine-pentaacetic acid–Zn) (DTPA-Zn) concentrations, which resulted in a direct increase in Zn uptake by the plants, since a significant correlation was observed between the DTPA–Zn contents and plant Zn uptake. However, the main reason for the increase in plant Zn uptake under earthworm inoculation was probably the increase in dry matter production stimulated by earthworms.  相似文献   
187.
Summary The interaction between soil pH and inoculation with rhizobia and vesicular-arbuscular mycorrhizae (VAM) was studied in an industrially polluted soil contaminated with high levels of Zn and Cd. A silt loam soil (pH 6.7) was amended with Ca(OH)2 or elemental S to adjust the soil pH to 4.3, 5.3, 6.0, and 7.2. Alfalfa (Medicago sativa L.) was planted in each treated soil an subsequently inoculated with Rhizobium meliloti and/or a mixed VAM spore population. Alfalfa growing in soils at a pH of 4.3 and 5.3 failed to survive as a result of soil acidity and heavy metal toxicity. At the three higher pH values, growth and foliar N and P were significantly increased by inoculation with rhizobia or VAM. The greatest increase was observed when both VAM and rhizobia were inoculated together into the soil. With a soil pH of 6.0 and 6.7, the available heavy metal concentration in the soil was high and the VAM significantly decreased heavy metal uptake from these soils. The foliar concentration of Zn was reduced from 455 to 306 g g–1 by inoculation with VAM (pH 6.0). At the highest soil pH (7.2), however, available heavy metal concentrations were generally lower and NAM significantly increased the heavy metal uptake. The influence of VAM on heavy metal uptake thus appears to be partly a function of the available heavy metal content in the soil.  相似文献   
188.
我国北部绵羊脱毛症与锌营养状况关系的探讨   总被引:1,自引:0,他引:1  
 通过对绵羊脱毛症流行病学的调查、临床症状和病理变化的观察,以及对牧草、饮水和绵羊血浆锌状况的检测,得出绵羊脱毛症是一种自然缺锌症。本研究采用可控可溶锌玻璃丸治疗绵羊脱毛症,效果好,方法简便,不用重复多次给药,一次给丸即解决问题,且未见任何中毒及其它异常迹象。  相似文献   
189.
用缺Cu,缺Zn与缺Cu、Zn的木村B营养液培养两个水稻杂交组合(威优35,威优49)与一个常规稻品种(测49)的幼苗。至七叶期,缺Zn与缺Cu、Zn培养的稻苗,新叶脉间均出现黄白色条纹,叶片呈卷曲状的缺Zn症状。凡是缺素培养的与对照比较,根数、特别是白根数都明显减少,株高降低,根与叶中的超氧物歧化酶(SOD)活性也均比对照低,其中根的SOD活性下降的更明显,尤以缺Cu、Zn培养的SOD活性下降的更显著。生育后期(孕穗期至黄熟期)的块素培养对SOD活性与产量的影响则比较小。  相似文献   
190.
以富锌的青春双歧杆菌ys01、德氏乳杆菌保加利亚亚种1.1480和嗜酸乳杆菌ysh2混合菌体作为富锌酸奶发酵剂发酵制备富锌酸奶,通过单因素试验和Box-Behnken试验对富锌酸奶的发酵条件进行优化,并考察其主要品质.富锌酸奶最佳发酵条件为:奶粉13%、蔗糖6%、葡萄糖酸锌39.1 mg/kg、变性淀粉1.3%,接种量4.2%、发酵温度41℃、发酵时间6h.在该条件下,富锌酸奶感官总分为8.9,蛋白质、脂肪、非脂乳固体和乳酸菌数等主要技术指标符合GB19302的相关规定,其有机锌含量为6.2mgkg.  相似文献   
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