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11.
硼氢化钠的水解产物是一种新的储氢材料,其良好的可逆储氢能力在5MPa氢气压力真空条件下3分钟后在室温下吸收氢150。根据报道,它已被证明,这两种改变的催化剂NaBH4水解和添加催化剂直接插入接口是两个非常有效进一步提高接口的储氢容量。对hpsb-y2o3脱氢TiO2分别掺杂均达到重量2.4%和重量4.6%。重要的是对hpsb-y2o3可逆的脱氢能力不下降后成功———超循环。相比之下,对hpsb-ceo2可逆脱氢高达到重量5.9%,在室温下5分钟后3MPa氢气压力150氢吸附。 相似文献
12.
丁酸钠是一种绿色新型饲料添加剂,目前在动物饲料中应用广泛,且效果良好。作者主要介绍了丁酸钠的生物学功能、对犊牛胃肠道发育的影响及其在犊牛日粮中的应用效果。重点总结了丁酸钠促进犊牛胃肠道发育的影响机制,包括作为胃肠道组织的能量来源调控激素和生长因子的分泌,提高消化和吸收相关酶的分泌及活性,提高肠道免疫细胞保护性蛋白的分泌等。现有研究表明,日粮干物质中添加0.3%丁酸钠就能达到促进犊牛生长和胃肠道发育的效果,但具体添加水平、添加阶段和方式等尚不明确。此外,日粮粗饲料水平、精料发酵所产生的内源丁酸对外源丁酸钠的作用效果是否有影响也鲜有报道,有待进一步开展研究。 相似文献
13.
M. Rokebul Anower M. D. Peel I. W. Mott Y. Wu 《Journal of Agronomy and Crop Science》2017,203(6):506-518
We previously reported an alfalfa half‐sib family, HS‐B, with improved salt tolerance, compared to parental plants, P‐B. In this study, we conducted additional experiments to address potential physiological mechanisms that may contribute to salt tolerance in HS‐B. Vegetatively propagated HS‐B and P‐B plants were treated with a nutrient solution (control) or a nutrient solution containing NaCl (EC = 12 dS/m). Shoots and roots were harvested at various time points after treatment for quantification of proline, soluble sugar, and H2O2 using spectrophotometers. Subcellular localization and quantification of Na in roots were conducted using a Na+‐specific dye under a confocal microscope. HS‐B produced 86 and 89% greater shoot and root dry biomass, respectively, compared to parental plants, P‐B, under salinity in the greenhouse. Under saline conditions the HS‐B shoots accumulated 115% and roots 55% more soluble sugars than P‐B counterparts. The non‐saline HS‐B shoots, however, showed 72% less soluble sugars than the non‐saline P‐B plants. Under saline conditions HS‐B accumulated 39% less proline in shoots, while roots accumulated 56% more proline, compared to their P‐B parents. HS‐B plants also showed a greater reduction of stomatal conductance under mild saline stress. HS‐B shoots and roots contained 3–4 times less reactive oxygen species (H2O2) after salt treatment compared to P‐B plants. Sodium localization and distribution analysis using Na+‐specific dye revealed HS‐B plants accumulated 88% and 48% less Na+ in stele and xylem vessels compared to P‐B. The study provides insights into the potential mechanisms that may contribute to salt tolerance in HS‐B: maintaining RWC by accumulating soluble sugars while reducing transpiration, maintaining healthy status by reducing oxidative stresses, and preventing salt toxicity by reducing accumulation of Na+ inside root cells and xylem. 相似文献
14.
The Bemisia tabaci whitefly is an important pest of many agricultural crops. Direct feeding by this pest can cause physiological plant symptoms including irregular ripening in tomatoes and silverleaf disorder in squash. In addition, B. tabaci can transmit more than 100 plant viruses that cause severe diseases that affect crop yield and quality. Insecticides are often applied to control this pest and they may be applied to the foliage and/or to the soil. Insecticides that kill quickly or cause feeding cessation reduce the damage caused by B. tabaci on the host plant most effectively. In this study fluorescence was used to assess B. tabaci feeding and to determine the effect of systemically applied insecticides on feeding by the pest. Cyantraniliprole (Verimark™) and imidacloprid (AdmirePro®) produced a rapid reduction in B. tabaci feeding. At 24 h after a systemic application, the percentage of whitefly nymphs still feeding in plants treated with cyantraniliprole (anthranilic diamide) and imidacloprid (neonicotinoid) were 19% and 33%, respectively. Both products showed a good reduction in insect feeding and since they have different modes of action they should be considered as rotational partners for B. tabaci control in areas where there is no resistance to neonicotinoid insecticides. While the fluorescein sodium salt cannot be used to trace the uptake of insecticides, it has been shown to reliably demonstrate feeding cessation of whitefly nymphs after foliar and systemic applications of insecticides. 相似文献
15.
16.
A method for fractionating sorghum proteins using extraction solvents and techniques designed to obtain polymeric protein structures (especially disulfide linked) was developed. Extraction and separation conditions were optimized in terms of completeness of protein extraction, sample stability, and analytical resolution. After pre-extraction of albumins and globulins, a 3-step sequential procedure involving no reducing agents was applied to ground whole sorghum flour. The three fractions obtained represented proportionally different protein polymer contents and molecular weight distribution as evidenced by comparative size exclusion chromatography. Protein composition also varied among the extracts with differences in kafirin composition and non-kafirin proteins detected in the fractions by RP-HPLC and SDS-PAGE analysis. The ability to quantify and further characterize sorghum polymeric protein complexes will be useful for additional studies linking protein structures with functionality and digestibility and variations for these properties within diverse sorghum germplasm. 相似文献
17.
本试验旨在研究硬脂酰乳酸钠(SSL)对断奶仔猪生长性能、血清生化指标及养分表观消化率的影响。试验选择25日龄的断奶仔猪336头,按体重随机分为6组,每组7个重复,每个重复8头猪。各组仔猪饲粮中SSL添加水平分别为0(对照)、250、500、750、1 000和2 000 mg/kg,试验分2个阶段,每阶段21 d。试验测定仔猪生长性能,谷丙转氨酶、谷草转氨酶、总胆固醇等血清生化指标及能量、干物质、氮和粗脂肪表观消化率。结果表明:与对照组相比,1)饲粮中添加500、750和1 000 mg/kg SSL能显著降低仔猪第2阶段料重比(P0.05),添加1000 mg/kg SSL显著降低全期料重比(P0.05);2)饲粮中添加SSL有降低试验第42天仔猪血清谷草转氨酶、谷丙转氨酶活性,增加血清高密度蛋白胆固醇含量及高密度蛋白胆固醇/低密度蛋白胆固醇值的趋势,且当添加水平为2 000 mg/kg时差异达到显著水平(P0.05);3)饲粮中添加SSL能显著提高粗脂肪表观消化率(P0.05),并且有提高氮及能量表观消化率的趋势,当添加水平为2 000 mg/kg时差异达到显著水平(P0.05)。结果提示,饲粮添加SSL能降低仔猪料重比,提高饲料养分尤其是粗脂肪的表观消化率。 相似文献
18.
为了探究添加亚油酸条件下不同剂量硝酸钠对水牛瘤胃体外发酵脂肪酸组成及相关微生物数量的影响,本试验选用3头装有永久性瘤胃瘘管的母水牛,以精粗比40∶60为底物进行瘤胃液体外发酵试验。试验组硝酸钠的浓度分别为1、2、3 mg·mL-1,对照组不加硝酸钠,每组均添加0.25 mg·mL-1的亚油酸,每组各5个重复。在体外培养3、6、9、12、24 h时测定产气量和甲烷产量,24 h结束培养,测定瘤胃体外发酵参数、脂肪酸含量及瘤胃微生物数量。结果表明:1)添加硝酸钠显著降低了总产气量和甲烷产量(P<0.05);2)添加硝酸钠pH值和氨态氮(NH3-N)含量显著升高(P<0.05),异丁酸和异戊酸含量显著降低(P<0.05),而对总挥发性脂肪酸(TVFA)含量无显著性影响(P>0.05);3)添加1 mg·mL-1硝酸钠,C18:2cis-9,trans-11、C18:2trans-10,cis-12含量和不饱和脂肪酸/饱和脂肪酸(UFA/SFA)显著高于其他组(P<0.05),且C20:5n3 (EPA)含量显著高于添加3 mg·mL-1硝酸钠组(P<0.05),添加2 mg·mL-1硝酸钠C22:6n3 (DHA)含量显著高于其他组(P<0.05);4)添加硝酸钠组原虫数量显著低于对照组(P<0.05),添加2、3 mg·mL-1硝酸钠产甲烷菌数量显著低于添加1 mg·mL-1硝酸钠组(P<0.05),添加1 mg·mL-1硝酸钠总细菌、真菌、溶纤维丁酸弧菌、蛋白分解丁酸弧菌、非典型丁酸弧菌、亨氏丁酸弧菌数量显著高于其他组(P<0.05)。由此可得,体外法添加1~3 mg·mL-1硝酸钠和0.25 mg·mL-1亚油酸在维持水牛TVFA含量不变的情况下显著降低了甲烷含量,且1 mg·mL-1硝酸钠能促进亚油酸生成共轭亚油酸(CLA),优化脂肪酸组成,并能增加大多数瘤胃微生物的数量。 相似文献
19.
Tanya Duke-Novakovski Carolina Palacios Jimenez Masako Fujiyama Shannon G. Beazley 《Veterinary anaesthesia and analgesia》2021,48(1):17-25
ObjectiveVarious drugs administered to horses undergoing surgical procedures can release histamine. Histamine concentrations were evaluated in horses prepared for surgery and administered butorphanol or morphine intraoperative infusions.Study designProspective studies with one randomized.AnimalsA total of 44 client-owned horses.MethodsIn one study, anesthesia was induced with xylazine followed by ketamine–diazepam. Anesthesia was maintained with guaifenesin–xylazine–ketamine (GXK) during surgical preparation. For surgery, isoflurane was administered with intravenous (IV) morphine (group M: 0.15 mg kg–1 and 0.1 mg kg–1 hour–1; 15 horses) or butorphanol (group B: 0.05 mg kg–1 and 0.01 mg kg–1 hour–1; 15 horses). Histamine and morphine concentrations were measured using enzyme-linked immunoassay before opioid injection (time 0), and after 1, 2, 5, 30, 60 and 90 minutes. In a subsequent study, plasma histamine concentrations were measured in 14 horses before drug administration (baseline), 15 minutes after IV sodium penicillin and 15 minutes after starting GXK IV infusion. Statistical comparison was performed using anova for repeated measures. Pearson correlation compared morphine and histamine concentrations. Data are presented as mean ± standard deviation. Significance was assumed when p ≤ 0.05.ResultsWith histamine, differences occurred between baseline (3.2 ± 2.4 ng mL–1) and GXK (5.2 ± 7.1 ng mL–1) and between baseline and time 0 in group B (11.9 ± 13.4 ng mL–1) and group M (11.1 ± 12.4 ng mL–1). No differences occurred between baseline and after penicillin or between groups M and B. Morphine concentrations were higher at 1 minute following injection (8.1 ± 5.1 ng mL–1) than at 30 minutes (4.9 ± 3.1 ng mL–1) and 60 minutes (4.0 ± 2.5 ng mL–1). Histamine correlated with morphine at 2, 30 and 60 minutes.Conclusions and clinical relevanceGXK increased histamine concentration, but concentrations were similar with morphine and butorphanol. 相似文献
20.
试验旨在研究氯前列醇钠、产前背膘厚、便秘对后备母猪同期分娩集中度和生产性能的影响,并进一步探讨母猪同期分娩的最优方案。选取后备母猪共295头,根据妊娠期110 d时P2点处的背膘厚,随机分为3组:对照组(CON组:0.9%生理盐水)、低剂量氯前列醇钠组(LPG组:0.1 mg氯前列醇钠)、高剂量氯前列醇钠组(HPG组:0.2 mg氯前列醇钠),于妊娠期114 d进行阴户部注射诱导分娩。结果表明,与对照组相比,高、低剂量氯前列醇钠均可显著缩短母猪从注射到分娩的时间间隔(P<0.05),且两试验组间差异不显著(P>0.05)。但是,LPG组后备母猪在注射氯前列醇钠后48 h内的分娩率高达95%,并且白天分娩率达75.7%。此外,LPG组后备母猪的产仔间隔也显著短于CON组(P<0.05)。同时本研究发现,背膘厚在16~20 mm范围内的后备母猪从注射到分娩的时间间隔显著短于背膘厚≤15 mm的后备母猪(P<0.05);便秘指数0~1.0组后备母猪的产程和产仔间隔均显著大于便秘指数1.1~2.0组及2.1~3.0组的后备母猪(P<0.05)。进一步回归分析发现,母猪背膘厚分别与产程、总产仔数、活仔数存在极显著线性相关(P<0.01),母猪便秘指数分别与产程、产仔间隔、总产仔数、活仔数存在极显著线性相关(P<0.01)。综上所述,在妊娠期114 d对后备母猪阴户部注射0.1 mg氯前列醇钠诱导分娩,不仅可显著加快母猪分娩的进程,而且还可大大节约药物成本。此外,母猪产前背膘厚和便秘均会影响母猪同期分娩的效果,应使母猪分娩前保持最佳的背膘厚(16~20 mm),且避免母猪便秘,方可保证同期分娩的顺利实施。 相似文献