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91.
92.
掺杂对酸法铁黄制备过程的影响   总被引:5,自引:0,他引:5  
研究了酸法铁黄制备过程中掺杂Zn^2+,N^2+,Cd^2+,Cr^3+,PO4^3-等离子对晶种及铁黄形态和结构的影响,并初步探讨了杂质的作用机制。研究发现:掺杂离子改变晶种及铁黄的形态和结构,掺杂Zn^2+可增加晶种轴比,减少枝权和孪晶,优化铁黄形态。  相似文献   
93.
作物种子的电生物效应与电场强度关系的研究   总被引:15,自引:6,他引:15  
用不同强度的匀强电场作用油葵种子一定时期发现不同电场强度对应不同程度的生物响应,场强与响应呈振荡型关系。  相似文献   
94.
筛分机的工作参数是影响筛分机分级效率和生产能力的重要因素。通过对白瓜子筛分机工作参数的试验分析,确定了有别于文献介绍的筛分机工作参数,修正了筛分机工作转速的经验公式。  相似文献   
95.
本文以最优静电处理参数下刺槐、紫穗槐、沙棘播种苗为研究对象。采用Logistic方程和t-检验方法对3种苗木年高生长节律和其它生长性状进行了分析和评价,结果表明,静电处理林木种子苗木生长效应是提高了出苗速率;改变了年生长节律—速生期提前和变短、瞬时生长速率增大、抗逆性能提高;改善了苗木生长性状、增加了生物量。为提高单位面积苗木产量和质量,探索了一条切实可行的新途径。  相似文献   
96.
琼花种子萌发规律及播种技术研究   总被引:1,自引:0,他引:1  
  相似文献   
97.
In this study, a Standard Operating Procedure (SOP) for the large-scale extraction, enrichment, and separation of suffruticosol B (SB), trans-ε-Viniferin (TV), trans-gnetin H (TG) from oil tree peony seeds shell (PSS) was successfully constructed. The ultrasonic-assisted extraction (UAE), macroporous adsorption resin (MAR), and column chromatography (CC) were employed to extract, enrich and separate SB, TV and TG from PSS, and the conditions were optimized. The results implied that SB (1.6937 g), TV (0.5884 g) and TG (3.8786 g) with the purity of 99.67 %, 99.32 % and 98.54 %, respectively, were obtained after the extraction, enrichment and separation. The total yields of the SB, TV and TG were 0.61 mg/g, 0.02 mg/g and 6.64 mg/g with the total extraction rates at 70.55 %, 69.77 % and 78.36 %, respectively. This is the first report on the large-scale extraction, enrichment and separation of oligostilbenes. The SOP in this paper could produce high purity SB, TV and TG, and provide a new idea for PSS as a new oligostilbene resource. The study expands the new development and research field of PSS and provides theoretical support for the green utilization of oil tree peony.  相似文献   
98.
This study aimed to investigate the effect of pumpkin (Cucurbita maxima) seed supplementation on the anthropometric measurements, biochemical parameters, and blood pressure (BP) of Indian women with metabolic syndrome (MetS). Initially, in vitro antioxidant activities of pumpkin seeds extract were assessed using standard methods. In vitro alpha-amylase, alpha-glucosidase, and dipeptidyl peptidase IV (DPP-IV) inhibition effects, along with glucose uptake assay using 3T3-L1 cell lines were performed to determine the antidiabetic effects of the seeds extract. Fatty acids and phytoconstituents were identified using gas chromatography-mass spectrometry (GC–MS). Indian women aged 30–50 years, having MetS were assigned either to intervention (n = 21) or control (n = 21) group on a random basis. Participants in the intervention group received 5 g of pumpkin seeds for 60 days. Participants in both intervention and control were advised to follow certain dietary guidelines throughout the study. Pumpkin seeds extract exhibited not only strong reducing power but also scavenged DPPH and ABTS●+ free radicals with low IC50 values. Pumpkin seeds inhibited alpha-amylase, alpha-glucosidase, and DPP-IV enzymes at varying concentrations with IC50 values of 138, 22, and 246 µg/mL, respectively. Furthermore, glucose uptake was enhanced by 213% at 300 ng/mL on the 3T3-L1 cell line. GC–MS analysis showed the presence of propyl piperidine, flavone, oleic acid, and methyl esters of fatty acids in the seed extract. On comparing the changes in mean reduction/ increment in the anthropometric measurements as well as biochemical parameters and BP between the groups, significant difference (P = 0.012) was observed only for fasting plasma glucose. Findings of the present study highlight the role of pumpkin seeds as a cost-effective adjunct in treating MetS.  相似文献   
99.
The aim of the present study was to magnetize Plantago ovata Forssk. hydrogel and produce a nanosphere system to carrier mefenamic acid as the drug model. For this propose, P. ovata seeds hydrogel (POSH) was extracted and magnetized by Fe3O4 being functionalized using tetraethyl orthosilicate and trimethoxyvinysilane. Thereafter, mefenamic acid (MFA) was loaded on the carrier system. The final product, as the magnetic drug loaded nanosphere (Fe/POSH/MFA), was fully characterized through different techniques involving X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating-sample magnetometer (VSM), thermal gravimetric analysis (TGA), dynamic light scattering (DLS), and FT-IR spectroscopy. The results confirmed the successful production of the drug loaded nanosphere system with particles magnetization of 25 emu/g over a range size of 40–50 nm. However, the size distribution less than 100 nm was measured through DLS analysis. The hydrogel showed a pH sensitivity swelling behavior representing the best efficacy at pH 7.4. The efficiency of the drug encapsulation was found to be 64.35%. The drug releasing was studied using a dialysis bag at pH = 7.4. The highest in vitro drug releasing was found to be 57.3 ± 0.6% after 72 h, as well. The findings of the current report account for the potential use of P. ovata hydrogel as an effective delivery system for encapsulation of water insoluble basic drugs, e.g., MFA in a magnetized carrier system.  相似文献   
100.
在不含有机模板剂体系(OSDAs)中,利用异相晶种(T型分子筛)诱导快速合成出纯相的低硅菱沸石分子筛。采用XRD、SEM、TEM、27Al MAS NMR和紫外拉曼等手段表征分子筛的结构属性和形貌特点。详细研究了菱沸石分子筛的晶化过程以及晶种添加量、nAl2O3/nSi O2、nH2O/nSiO2和碱度对菱沸石分子筛晶化的影响,并探讨T型分子筛晶种诱导合成菱沸石分子筛的晶化机理。原位合成体系中仅形成L型分子筛晶相,而一定量T型分子筛异相晶种的加入诱导溶胶快速制备出纯相的菱沸石分子筛。T型分子筛晶体在一定的水热条件下不断溶解而释放的六元环(6R)和四元环(4R)迅速形成菱沸石分子筛特征笼(CHA笼),抑制了L型分子筛特征单元和特征笼(不含四元环的CAN笼)的形成。  相似文献   
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