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1.
几种缓释肥的氮释放特性以及对草坪草生长的影响 总被引:6,自引:2,他引:6
实验室内采用水浸泡法对尿素、3种缓效肥和山西省农业科学院土壤肥料研究所研制(自研草坪肥)的缓效肥的初期溶出率和微分溶出率进行了测定.其中尿素的初期溶出率为22.75%,超出了国际上公认的缓/控释肥的初期溶出率小于15%的指标,而微分溶出率为0.22%,也小于国际上公认的缓/控释肥的微分溶出率(0.25%~2.5%)指标.其他几种缓释肥的初期溶出率为8.73%~14.42%,微分溶出率为0.30%~2.11%,符合国际上公认的缓/控释肥的初期溶出率和微分溶出率指标.田间试验比较和研究了尿素、3种缓效肥和山西省农业科学院土壤肥料研究所研制的缓效肥对草坪草的干草产量和养分含量的影响,尿素和包衣尿素处理的草坪草的生长量前期较高,后期产草量较低,呈马鞍型.其他处理的草坪草干草产量则比较平缓,肥料的氮释放特性与草坪草生长趋势相同.不同肥料处理对草坪草的中量、微量元素含量有一定的影响. 相似文献
2.
Sorghum was germinated for different time (12, 24, 36 and 48 h) at different temperatures (25, 30 and 35 °C) and the changes in their nutritional and functional properties of germinated sorghum flour were assessed and compared with native sorghum flour. Germination inversely affects the crude protein, fat, fibre and ash content. A decrease in water absorption and swelling power and increase in oil absorption capacity was observed due to enzymatic starch modification as the germination duration progressed. Germination of sorghum increased the gel consistency while paste clarity was decreased as compared to native flour. Proteins were modified by action of enzymes during higher germination time and temperature conditions, which results in significantly higher protein solubility of germinated sorghum flour, which also result in enhancing the foaming and emulsifying properties of the flour. Lowest % synersis value and least gelation concentrations were observed in native sorghum has, which increased during germination and were highest in sorghum germinated for 48 h at 35 °C. Germination in overall can be used as low cost natural bio-processing technique for the preparation of modified flour with enhanced function properties without chemical modification or genetic engineering. 相似文献
3.
Erin L Deters Allison J VanDerWal Katherine R VanValin Stephanie L Hansen 《Journal of animal science》2021,99(6)
To assess the relative bioavailability of bis-glycinate bound Cu, 90 Angus-cross steers (265 ± 21 kg) were blocked by body weight (BW) to pens with GrowSafe bunks and randomly assigned to dietary treatments (14 to 18 steers/treatment): 0 mg supplemental Cu/kg dry matter (DM; CON), 5 or 10 mg supplemental Cu/kg DM as Cu sulfate (CS5; CS10) or bis-glycinate bound Cu (GLY5; GLY10). Steers received a high antagonist growing diet (analyzed 4.9 mg Cu/kg DM, 0.48% S, and 5.3 mg Mo/kg DM). Steers were weighed at the beginning (days 1 and 0) and end (days 125 and 126) of the trial to determine average daily gain (ADG) and gain:feed (G:F). Blood was collected from all steers on days 0, 28, 56, 84, and 126. Liver samples were collected on days −3 or −2 and day 123 or 124. Data were analyzed using ProcMixed of SAS (experimental unit = steer; fixed effect = treatment and block). Plasma Cu was analyzed as repeated measures (repeated effect = day). Plasma and liver Cu concentrations were regressed against total Cu intake using ProcGLM to calculate relative bioavailability of GLY. Final BW and overall ADG were greatest for CS5 and CS10 and least for CON and GLY5 (P = 0.01). Overall, DMI was not affected by treatment (P = 0.14), but overall G:F tended to be greatest for CS5, CS10, and GLY5 and least for CON (P = 0.08). Total and supplemental Cu intake was greatest for steers supplemented either source at 10 mg Cu/kg DM and least for CON (P < 0.01). However, total and supplemental Cu intake was greater for CS5 than GLY5 (P < 0.01). Final liver Cu concentrations were greatest for CS10, least for CON, CS5, and CS10, and intermediate for GLY10 (P < 0.01). Final plasma Cu was greatest for steers supplemented either source at 10 mg Cu/kg DM (P < 0.01). Relative bioavailability of GLY was 82% compared to CS based on liver Cu (P < 0.01) but did not differ based on plasma Cu (P = 0.60). The lesser bioavailability of GLY relative to CS could be due to a high concentration of dietary antagonists and lower solubility of GLY (68.9% relative to CS) in pH conditions (5.2) similar to the ruminal pH of a beef animal consuming a high concentrate diet. Future studies should examine the effects of bis-glycinate bound Cu fed in blended combination with inorganic Cu sulfate to determine the most effective blend of sources for feedlot cattle experiencing varying amounts of dietary Cu antagonists. 相似文献
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6.
Fazli Wahid Muhammad Sharif Muhammad Adnan Imtiaz Ali Khan Emre Aksoy 《Journal of plant nutrition》2013,36(15):1760-1769
AbstractInoculation effect of arbuscular mycorrhizal fungi (AMF) on phosphorus (P) transfer from composted dung of cattle with a diet supplemented with powdered rock phosphate (RP) and their successive uptake by mung bean plants was assessed in alkaline soil. The efficacy of composted RP fed dung alone or/and in combination with AMF inoculums containing six different species were compared with SSP in six replicates per treatment in pots. The results showed that the association of AMF with composted RP fed dung had a positive effect on mung bean shoot (3.04?g) and root (2.62?g) biomass, chlorophyll (a, b), carotenoid contents and N (58.38?mg plant?1) and P (4.61?mg plant?1) uptake. Similarly, the percent roots colonization (56%) and nodulation of mung bean plant roots and their post-harvest soil properties were also improved by the inoculation of AMF together with composted RP fed dung. It is concluded that the combined application of AMF with composted RP fed dung has almost the same effect as SSP for improving mung bean plants growth and their nutrients uptake. Moreover, AMF inoculants can be used as a suitable biofertilizer in combination with locally available organic sources of fertilizers for improving P status and growth of plants in alkaline soils. 相似文献
7.
生物质灰及灰中化学元素的水溶特性是其是否能作为肥料应用的主要指标,成灰温度会影响这些特性。该文试验研究了成灰温度在400~800℃范围内,3种主要农业废弃物麦秸、玉米秸、稻壳的灰的水溶性和灰中各元素的水溶性。结果表明:1)麦秸灰、玉米秸灰的水溶性明显高于稻壳灰,三者水溶性都随成灰温度增高而显著降低,温度从400升高到800℃,水溶性分别从48%,35%和12%降至约12%,8%和0。2)灰中水溶元素主要有K,Cl和S,其中,K和Cl的水溶性随着成灰温度升高而降低,而S的水溶性几乎不受成灰温度的影响。 相似文献
8.
几种包膜缓控释肥粒养分释放特征的研究 总被引:1,自引:0,他引:1
采用水浸泡法对国内外4种包膜控释肥料的养分释放特性进行了系统的研究。结果表明,4种缓控释肥料的初期溶出率均小于12%,微分溶出率在0.4%~1.5%之间,这符合国际上公认的缓/控释肥的评价标准,初期溶出率小于15%、微分溶出率在0.25%~2.5%之间。采用水浸泡法测定包膜控释肥料养分释放特征,简便快速,检测时间短,重复次数少,养分浓度变化直接反映出包膜控释肥料的释放速率特性,还可以定量的测定其供肥性能,控释肥料有控制养分释放、延长供应时间的作用;其中腐殖酸和炭基有利于提高肥料颗粒的水稳定性,减缓养分的释放速率。 相似文献
9.
膜技术在茶叶深加工中的应用研究 总被引:3,自引:1,他引:3
选用0.1μm微波膜对茶水提离心上清液进行微波处理,探讨了微滤温度对干物率、咖啡碱、各儿茶素组分以及微滤处理对产品冷溶性的影响。同时,选用不同的超滤膜对儿茶素粗提液进行超滤处理,比较分了超滤处理对儿茶素各组分比值和儿茶素终端产品色素的影响。结果表明,微滤滤出液的干物率、咖啡碱及各儿茶素组分含量随微滤温度的升高而增加,产品的各项冷溶性指标明显好于对照样产品;选用超滤膜-1可获得酯型儿茶素/非酯型儿茶素比值较小的产品,适用超滤膜-2可获得比值较大的产品;超滤膜-12比超滤膜-2能更有效地去除儿茶素终端产品色素。 相似文献
10.
采用RP-HPLC法和摇瓶法测定了人参皂苷Rd在水和不同pH介质中的平衡溶解度及其在正辛醇-水及各pH介质组成的体系中的表观油水分配系数(P_(app)),并考察了人参皂苷Rd在4个强降解条件下的降解情况。结果表明:在25℃时,人参皂苷Rd在水(pH 7.0)和不同pH(1.0,2.0,4.0,5.8,6.8,7.4)介质中的平衡溶解度依次为0.224,0.015,0.050,0.116,0.136,0.439,0.201 g/L;人参皂苷Rd在水中的Papp=32.45(lg Papp=1.51),在不同pH介质中的油水分配系数均接近或大于1;人参皂苷Rd在0.1 mol/L Na OH、0.1 mol/L HCl、70℃、0.3%H2O24个强降解条件下,放置7 d后的降解率分别为20.02%、88.53%、28.15%、69.81%。上述研究结果表明:人参皂苷Rd极微溶于水,脂溶性好,且不同的pH对其溶解度和Papp均具有较大影响,在碱和高温条件下较稳定,在酸和氧化条件下降解较快。 相似文献