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201.
粗硫酸盐松节油精制研究   总被引:2,自引:2,他引:0  
粗硫酸盐松节油是硫酸盐法制浆生产的副产品,因其含有许多硫化物故有恶臭味和较深的颜色,不能直接使用.为扩大其用途,须对其进行精制.本文通过正交实验得出:先用多种酸进行预处理后,再用4%用量的浓度为30%的过氧化氢溶液经水蒸气蒸馏后达到脱色除臭的精制目的  相似文献   
202.
稳定钡离子的聚合物阻垢剂的合成与性能评价   总被引:1,自引:0,他引:1  
介绍了以顺丁烯二酸酐,丙烯酸,醋酸乙烯酯为单体,水为溶剂,过硫酸铵为引发剂,合成三元共聚物阻垢剂;研究了聚合条件对该共聚物阻硫酸钡垢的性能影响,确定了合成的聚合工艺。试验结果表明,该共聚物阻垢剂阻硫酸钡垢效果优异,最高阻垢率可达92.1%。  相似文献   
203.
OBJECTIVE: To identify any systemic effects of topical and subconjunctival administration of atropine sulfate in the horse. Animals studied Six mature grade horses were treated hourly in one eye with topical ophthalmic atropine drops for 24 h. Five horses were treated subconjunctivally in one eye with 3 mg of atropine sulfate. Procedures Pupillary light reflexes, pupil size, electrocardiographic parameters, girth measurements, intestinal motility, and clinical signs of abdominal pain were monitored. RESULTS: Alteration in auscultated gut motility and clinical signs of abdominal pain were the most sensitive indicators of the systemic manifestations of the topically applied atropine. Gut motility was absent in all horses for periods of 2-18 h in all four abdominal quadrants in horses given topically administered atropine. Signs of abdominal pain were observed in four of six horses that received topical atropine. In the subconjunctival test study, gut motility was absent in three horses for periods of 3-7 h. Uniocular subconjunctival injection of 3 mg atropine sulfate produced signs of abdominal pain in one of six horses. Conclusion The ophthalmic administration of atropine can affect gut motility and induce signs of colic in selected horses.  相似文献   
204.
The distribution of iron monosulifde (quantified as acid volatile sulfur:SAV) was compared with geochemical properties that are known to affect its formation and accumulation in three coastal Holocene acid sulfate soils (ASS) at Tuckean Swamp,Mc Leods Creek and Bungawalbyn Swamp respectively,These properties included pH,reactive iron(FeR),pore-water sulfate(SO4^2-) and organic carbon(OC).Iron monosulfide was concentrated at the oxic/anoxic boundary,the Tuckean Swamp and McLeods Creek sites are Holocene sediments,whereas the Bungawalbyn Swamp is a Holocene peat.The concentration of SAV averaged 0.2 g kg^-1 in a 0.5m thick soil layer at the Tuckean Swamp,but was an order of magnitude lower in the oxic/anoxic transition layers at McLeods Creek and Bungawalbyn Swamp,The SAV mineral greigite(Fe3S4) was identified in the Tuckean Swamp by X-ray diffraction and scanning electron microscopy with quantitative energy dispersive X-ray analysis(SEM-EDX),Very small concentrations of greigite were also observed in the McLeods Creek,based on crystal morphology and elemental composition.The concentration of SAV was a small fraction of the total reduced sulfur,representing at most 3% of the pyrite sulfur,However,the presence of this highly reactive sulfide mineral,distributed within pores where oxygen diffusion is most rapid,has important implications to the potential rate of acid production from these sediments.  相似文献   
205.
离子色谱法测定烤烟中氯离子和硫酸根离子及氟离子   总被引:19,自引:2,他引:17  
提出了用离子色谱法测定烤烟中氯离子和硫酸根离子及氟离子的方法.采用IonPacASl4A阴离子交换分离柱、8mmol/L碳酸钠和1mmol/L碳酸氢钠混合液为流动相,自动再生抑制型电导检测在15min内完成烤烟中F^-1,Cl^-1,SO4^2-的测定,建立起针对烤烟F^-1,Cl^-1,SO4^2-的离子色谱法分析方法.该法具有良好的线性(相关系数为0.9991~0.9999)和重复性(相对偏差小于4.31%),回收率为95.2%~103.1%.  相似文献   
206.
A 6-month field experiment (from October to March) was conducted in a 20-year-old experimental grove of the Aristotle University of Thessaloniki in order to enhance its micronutrient levels and assess the effect of micronutrient foliar application manganese, zinc and boron (Mn, Zn and B) on mineral nutrition, chlorophyll concentration and chlorophyll fluorescence parameters (Fv/Fm, Fv/F0 and Performance index, PI) of the olive trees (cv. “Chondrolia Chalkidikis”). The experiment consisted of four treatments (Control-C: trees sprayed with deionized water, T50: trees sprayed with 50 mg/L Mn, Zn and B, T100: trees sprayed with 100 mg/L Mn, Zn and B, T200: trees sprayed with 200 mg/L Mn, Zn and B); the three micronutrients were applied in the forms of manganese sulfate (MnSO4), zinc sulfate (ZnSO4) and boric acid (H3BO3), respectively. The results showed that the most effective treatment for the enhancement of foliar Mn and B levels was T200, while for the increase of Zn levels was T100. In addition, significant differences among the treatments were recorded for most leaf nutrient concentrations (with the exception of potassium (K), which was not influenced by foliar treatment, the other macronutrients, such as calcium (Ca), magnesium (Mg), phosphorus (P) and nitrogen (N), as well as iron (Fe), obtained their maximum concentrations, at the end of the experiment, in C or T50 treatment). Chlorophyll concentrations were not influenced by foliar treatment. Concerning chlorophyll fluorescence parameters (Fv/Fm, Fv/F0 and P index), significantly lower values were found in the control (C) trees, compared to the other three treatments, so it seems that a chlorophyll fluorescence technique may be used to detect micronutrient deficiencies in olive groves. However, from all the leaf nutrient concentrations determined, it was found that with the exceptions of: 1) Mn concentrations in the C, T50 and T100 treatments, which were marginal, or slightly deficient; 2) B and Zn concentrations in the C and T50 treatments, which were slightly deficient and marginal, respectively; 3) some K concentrations during the early spring period, which were slightly deficient, all the other concentrations were within the normal levels of sufficiency or within the optimum range, so no serious nutrient deficiency was detected.  相似文献   
207.
A rising global population necessitates continued genetic improvement of wheat (Triticum spp.), but not without monitoring of unintended consequences to processors and consumers. Our objectives were to re-establish trends of genetic progress in agronomic and milling traits using a generational meter stick as the timeline rather than cultivar release date, and to measure correlated responses in flour quality and human wheat-sensitivity indicators. Grain yield and kernel size showed stepwise increases over cycles, whereas wheat protein content decreased by 1.1 g/100 g. Reduced protein content, however, did not result in lower dough strength pertinent to bread baking. A novel method of directly testing gluten elasticity via the compression-recovery test indicated a general increase in gluten strength, whereas the ratio of total polymeric to total monomeric proteins remained stable. Also showing no change with genetic progress in yield were flour levels of gluten epitopes within the key immunotoxic 33-mer peptide. The oligosaccharide fructan, present in milled and wholemeal flours, increased with increasing grain yield potential. While yield improvement in U.S. bread wheat was not accompanied by a decline in gluten strength or systematic shift in a key wheat sensitivity parameter, the unanticipated rise in total fructans does implicate potentially new dietary concerns.  相似文献   
208.
用硫酸铵和聚乙二醇(PEG)沉淀技术对杨小舟蛾幼虫谷胱甘肽S-转移酶(GSTs)进行了纯化研究。结果表明:通过硫酸铵沉淀,杨小舟蛾GSTs活性主要分布在40%~60%沉淀段,比活力为174.41nmol/(min·mg),纯化倍数为1.39。在5种PEG(PEG400、PEG2000、PEG4000、PEG6000和PEG20000)中,PEG20000的纯化效果最好。杨小舟蛾PEG20000沉淀的GSTs活性峰主要分布在10%~15%沉淀段,GSTs比活力&454.14nmol/(min·mg),纯化倍数达到15.50。因而,PEG20000沉淀对于杨小舟蛾幼虫GSTs的纯化效果优于硫酸铵。  相似文献   
209.
在浅山地区进行了大白菜施用硫酸钾镁肥试验,试验结果表明:硫酸钾镁肥对大白菜的生育期和农艺性状影响不太明显,但有显著的增产作用,产量比对照增产10%以上,增产效果明显。  相似文献   
210.
宁夏自治区西吉县地下水中硫酸盐(SO42-)含量普遍超标,为了查明地下水中SO42-的来源,对区内36件地下水样品的水化学组成、21件岩石样品的易溶盐组分和10件地下水样品硫同位素组成进行了测试分析。结果表明:SO42-是区内地下水中主要阴离子组分,在区域上具有北部低,中部和南部高的明显的分带性,并且沿着地下水流向SO42-含量逐渐升高;SO42-也是区内第三系地层中主要的易溶盐组分,以石膏和芒硝形式存在;区内地下水中SO42-主要来源于地层中石膏和芒硝(所占比例平均为83%),其次是地层中的硫化物(所占比例平均为17%)。  相似文献   
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