Simultaneous determination of Cu(II), Zn(II), Fe(II), Mn(II), Co(II) and Ni(II) with a single sweep polarography

A new method of simultaneous determining Cu(II), Zn(II), Fe(II), Mn(II), Co(II) and Ni(II) with a single sweep polarography was developed. The experiment condition was studied and the results show that the optimum base solution is that the residue got from evaporating 25 mL mixed solution, 2.5 mL 1.0 mol/L ethylenediamine, 3.0 mL 1.0 mol/L ammonia-ammonium chloride, 5.0 mL 10 % sodium sulfite and 0.5 mL 0.5 % gelatin were mixed and diluted to 25 mL with water. Under the condition of this base solution, the polarography wave shapes of the six cations are ideal and without overlap of the peaks. In this base solution, Cu(II), Zn(II), Fe(II), Mn(II), Co(II) and Ni(II) in synthetic samples were determined with relative errors 0.4–9.4% and relative standard deviations 0.8%-12.2%. Under this experiment condition, one fold of Pb(II), Cr(VI) and Mo(VI) do not interfere with the determination for Cu(II). This method has been used to the simultaneous determination of the amount of the six cations in the samples of soil and Beiqi Tea. The relative standard deviations were 0. l%-2.1% and recoveries were 93.5%-99.0 %.     

Dynamics of Zn between soil and plant in Northeast Leymus chinensis grassland

A study was conducted to determine the dynamic of Zn content between soil and plant in the natural protection zone of Leymus chinensis grassland in Changling County (44°30′–44°45′N; 123°31′–124°10′E), Jilin Province, China. Results showed that the total Zn content was lower, available Zn content had a moderate level in the soil, and the plants was not lack of Zn. During the growing season, content of total Zn and available Zn in soil showed a down-trend distribution along the soil profile. Content of total Zn had a significantly positive correlation with that of the organic matter, but it was negatively correlated to soil pH. Monthly dynamic of the average content of total Zn showed a “V” type curve in the growing season from May to August, and July was the nadir. The trend of the average content of available Zn was similar to the content of total Zn, but was down after August; Zn content variation in the organs and litter of L. chinensis was great, with the order of root>rhizome >leaf>stem>litter. The ratio of available Zn content in A layer versus B layer was more than 2 times that of the total Zn, which indicated that the soil of A layer had higher enrichment capacity of available Zn. The enrichment of Zn in the root of L. chinensis was 44.17 times as that in the soil. The absorbing intensity of root had a significantly negative correlation with the activity of Zn in the soil (r=−0.8800, p<0.01). Biography: ZHOU Xiao-mei (1966–), female, Ph.D., associate professor of Jilin Normal University, Siping 136000, P.R. China.     

苎麻对重金属复合污染土壤的修复效率研究

通过盆栽试验模拟了砷(As)、铅(Pb)、锌(Zn)复合污染环境,并研究了复合污染环境下不同As浓度对苎麻生长及其重金属在植株体内吸收、富集和迁移的影响。结果表明,在复合污染情况下,低浓度(≤100 mg/kg)的As对苎麻生长没有显著影响,而高浓度的As可使苎麻植株变矮、叶片易损、分蘖数及生物量减少,但仍能完成正常生理周期并且无严重毒害症状出现。由此表明,苎麻对As/Pb/Zn复合污染土壤具有一定的耐受性。且在试验条件下,苎麻植株对As、Pb、Zn的转运系数分别在0.11~2.43、0.11~1.03和0.59~1.66之间,苎麻地上部对As、Pb、Zn的富集系数分别在0.01~0.45、0.01~0.12和0.17~1.48之间,表明苎麻可作为As、Pb、Zn单一或复合污染土壤修复的植物。     

Bioavailability of amino acids chelated and glass embedded zinc to rainbow trout, Oncorhynchus mykiss, fingerlings

A 2 × 4 factorial experiment was conducted to determine the bioavailability of zinc (Zn) from amino acids chelated (Zn–Am) and glass embedded Zn (Zn–Gl) as sources for rainbow trout, Oncorhynchus mykiss , fed practical type diets. Two levels of Zn (20 and 40 mg kg⁻¹) were supplemented to the diets using either zinc sulphate (Zn–Sf), zinc methionine (Zn–Mt), Zn–Am or Zn–Gl. Rainbow trout with an average weight of 2 g were fed the experimental diets for 15 weeks. Growth and feed gain ratio (FGR) were not significantly influenced by the dietary Zn content and forms. Alkaline phosphatase (ALP) activity for both levels of Zn–Am was significantly higher than that of Zn–Sf and Zn–Gl at 20 mg supplementation. In another experiment, fish of about 95 g were fed the same experimental diets to determine the absorption of Zn and it was found to be significantly higher from Zn–Am compared with the rest. Retention from Zn–Am at 20 mg was significantly higher than the rest, excluding Zn–Sf. The results suggest that the availability of Zn from Zn–Am might be superior among the sources compared.     

Binding characteristics of the Zn-binding membrane protein from common carp

ABSTRACT:    This study incorporated the 43 kDa Zn-binding membrane protein isolated from common carp into liposome. The specificity and strength of the binding of ⁶⁵Zn to the 43 kDa protein-liposomes, and the binding of the ⁶⁵Zn-labeled 43 kDa protein-liposomes to laminin were studied. It was found that ⁶⁵Zn was bound to the external side of the 43 kDa protein-liposomes. Specific binding of ⁶⁵Zn to the protein-liposomes was detected. The binding parameter of Zn to the protein was found to be: maximum binding site (N_max), 76.7 pmole/µg protein (approx. 3 mole of Zn²⁺/mole); and equilibrium dissociation constant (Kd), 0.19 µM. Of the cations introduced (Ca²⁺, Cd²⁺,Co²⁺, Cr²⁺, Cu²⁺, Fe²⁺, Hg²⁺, Mg²⁺, Mn²⁺, Ni²⁺, Pb²⁺), only Co²⁺ competed significantly with Zn. The protein-liposomes were also found to bind specifically to laminin with a N_max of 1.1 pmole/µg laminin, and Kd of 4.79 µM. No significant protein-liposome binding occurred to other extracellular matrix proteins (fibronectin, fibrinogen or vitronectin). Furthermore, the binding was specifically inhibited by the Arg-Gly-Asp (RGD) peptide or GRGDSPG, while two other analogs (GRGESPG and GRADSPG) were without effect.     

土壤施锌和叶面喷锌对风沙土玉米Zn吸收与积累的影响

【目的】研究土施和叶面喷施锌肥条件下玉米吸收、积累锌的规律,旨在为科学调控玉米锌营养状况、提高玉米籽粒锌含量提供理论依据。【方法】2011年在吉林风沙土地区采用大田试验,研究了土施锌肥(0kg/hm2(S0)、3.4kg/hm2(S3.4)、6.8kg/hm2(S6.8)、10.2kg/hm2(S10.2))和叶面喷施锌肥(0kg/hm2(F0),2.25kg/hm2(F))共计7个处理(S0F0(对照)、S3.4F0、S6.8F0、S10.2F0、S0F、S3.4F、S6.8F)对玉米各生育期植株锌含量、籽粒锌含量、籽粒产量和地上部分生物量以及锌肥利用率、Zn吸收总量和Zn吸收速率的影响。【结果】玉米植株中Zn的含量随着土施锌肥量的增加而增大,苗期较S0F0处理增加了2.7~8.5倍,其他生育期增加幅度有所降低;与S0F0处理相比,S3.4F0、S6.8F0、S10.2F0可以使玉米增产9.7%~37.7%,地上部分生物量增加6.2%~20.4%,玉米Zn吸收总量增加21.5%~81.9%。土施+叶面喷施锌肥处理比单独土施锌肥增产5.5%~17.0%,生物量增加18.5%~30.8%。【结论】土施+叶面喷施锌肥可以明显提高玉米籽粒锌含量和籽粒产量。     

不同畜禽粪肥与化肥配施下黑土中Zn含量及形态变化特征

通过培养实验并采用改进的BCR连续提取法研究了不同畜禽粪肥与化肥配施作用下黑土中Zn含量及形态在3年内动态变化特征。研究结果显示:不同畜禽粪肥与化肥配施增加了土壤中Zn总量和土壤各形态Zn含量,其中猪粪与化肥配施处理Zn总量为单施化肥处理的1.69倍,各形态Zn含量平均增幅达238.9%;不同畜禽粪肥与化肥配施还导致了Zn由生物有效性低的可氧化态和残渣态向生物有效性高的酸可提取态和可还原态转化,转化程度依次为猪粪与化肥配施鸡粪与化肥配施牛粪与化肥配施、单施化肥。在对影响Zn形态转化因素进行相关分析时发现:不论施肥与否,土壤中酸可提取态和可还原态Zn均与pH值、有机质含量呈显著负相关关系,而可氧化态和残渣态Zn与pH值、有机质含量呈显著正相关关系。此外,不同畜禽粪肥与化肥配施使得土壤中残渣态Zn与pH值间正相关性增强,而对各形态Zn与有机质含量间相关性影响不大。本研究条件下,畜禽粪肥与化肥配施造成了Zn在土壤中积累,提高了Zn的生物有效性,因而增加了土壤Zn污染风险;而不同粪肥间以猪粪与化肥配施对Zn污染影响最为显著,牛粪与化肥配施则与单施化肥差别不大。     

NYH-1型~(14)C核素高灵敏探测装置

本文描述了可测量低活度1 4 C核素的高灵敏探测装置。在FH 36 7探头的基础上进行了改装 ,更换了闪烁介质 ,增加了物质屏蔽和反符合屏蔽以及相应的电子线路。本装置对1 4 C的探测效率 ,植物干样为 6 93% ,土壤样为 3 2 % ,装置的本底计数为 2 35cpm     

肉牛微量元素锌锰碘营养状况的评价

在云南省会泽县和昭通市进行了 6个不同阶段的肉牛微量元素补饲试验 ,添加补充料后 ,肉牛日粮、血浆和血清中微量元素Zn、Mn和日粮I、血浆蛋白结合碘 (PBI)含量均有不同程度的增加 ,部分理化指标有显著变化 (P <0 0 5 ) ,表明在农村传统饲养模式下 ,肉牛微量元素Zn、Mn营养充足 ,但至少缺乏微量元素I,添加易吸收Zn、Mn对肉牛生产性能有一定的促进作用     

猪苓菌丝液体培养及富锌研究

对猪苓（Polyporus umbellatus Fr.)菌丝进行了液体培养及富集锌研究。结果表明，在培养温度22℃，PH7．0，振荡速度150r/min。培养基中锌添加量为40mg/kg时，猪苓菌丝的生物转化量及菌丝体富锌率最高。