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41.
针对广西农产品物流企业的特点,从众多影响企业品牌建设与发展的因素中,采用AHP-TOPSIS模型选择确定品牌全生命周期阶段对品牌竞争力影响力度最大的品牌元素,以实现品牌的可持续发展。  相似文献   
42.
Urban waste disposal occurred on fenland to the west of Manchester, England, between 1900 and 1964. The reclaimed fenland, Chat Moss, is now used for mixed arable farming. A total of 1.92 Mt of waste including privy midden, street sweepings, clinkers and slaughterhouse refuse was incorporated into the moss resulting in a modified topsoil with raised pH and reduced organic matter content compared with the subsoil. Elevated levels of potentially toxic elements (PTEs) are observed in the topsoil beyond the typical depth of atmospheric contamination; Cd and As concentrations exceed soil guideline values (SGVs) at 1.8 and 43 mg/kg, respectively. Sequential extraction indicates that waste‐derived Pb, Zn and Ni remain predominantly in the residual fraction, whereas Cu was mainly organically bound. Arsenic was predominately found in oxide and organic matter fractions with Cd in carbonate, oxide, organic matter and residual fractions. Pot trials indicated limited uptake of PTEs by vegetables grown on the waste‐amended soil, with the exception of Cd uptake by lettuce (0.22 mg/kg FW) and Pb uptake by radish (0.16 mg/kg FW), which exceeded current EU limits of 0.2 and 0.1 mg/kg FW, respectively. Hazard quotients (HQs) identified no risks to adults from consumption of vegetables grown in these soils with the exception of lettuce consumption with a HQ of 1.4. Risks to children were slightly greater with HQs >1 for Cd in lettuce, spinach, carrots and onion, As in lettuce, parsley and onion and for Zn in spinach.  相似文献   
43.
从赣南10个区县的沙质红壤、黏性红壤、紫色土和黄壤共131个果园采样测试了叶片营养元素含量,分析营养丰缺状况。赣南脐橙园普遍存在叶片N、K过量和Mg、Zn同时缺乏的问题。叶片N、P、K、Ca、Mg、Fe和 Mn在不同土壤类型的果园间存在显著性差异(P<0.05):沙性红壤果园P、Fe更为丰富。黏性红壤果园N含量最高,K的过量程度和 Mg的缺乏程度都最轻。黄壤果园P更丰富,Ca更缺乏,Mn最容易过量。紫色土果园N、P含量最低,K最易过量,Ca较丰富,Mg最缺乏,有部分pH较高的果园植株缺Fe。叶片S、Zn、Cu、B和Mo 在不同土壤类型的果园间差异不显著(P>0.05),但有相当比例的脐橙园叶片缺Cu,少量果园叶片缺B,所有果园叶片S和Mo在适宜范围内。赣南脐橙园叶片N、K过量和Mg、Zn缺乏的情况较为普遍,不同土壤类型的脐橙园叶片N、P、K、Ca、Mg、Fe和 Mn营养丰缺状况存在显著性差异(P>0.05)。  相似文献   
44.
OBJECTIVE: To determine the changes in Ca, P, Mg, Na, K, S, Cu, Fe and Zn concentrations of milk during the lactation in pasture-fed Thoroughbred mares and then calculate the dietary mineral requirements of the sucking foal and the lactating mare. PROCEDURE: Milk was sampled on days 1, 3, 7, 14, 21, 28 and at various times between 55 to 65, 85 to 95 and 135 to 150 days after parturition from 21 pasture-fed mares. The concentrations of macro- and micro-elements in the milk were determined by inductively coupled plasma emission spectrometry. RESULTS: Concentrations (mg/L) of these elements were highest in colostrum (Mg 302, Na 561, K 955, S 1035, Cu 0.76, Fe 0.79 and Zn 5.5) except for Ca (1245) and P (895), which where highest on day 7. The mean milk mineral element concentrations (mg/L) over days 55 to 150 were Ca 843, P 543, Mg 47, Na 120, K 590, S 219, Cu 0.19, Fe 0.34 and Zn 2.1. The mean plasma element concentrations (mg/L) over the same period were Ca 120, P 77.1, Mg 17.0, Na 3110, K 168, S 983, Cu 1.1, Fe 1.5 and Zn 0.49. Concentration gradients between plasma and milk were observed and, in the case of Ca, P, Mg, K and Zn, their concentrations in milk were greater than those in plasma, while a reverse situation was observed for Na, S, Cu and Fe. CONCLUSION: With the exception of Ca and P, the highest concentrations of mineral elements were observed in the colostrum. The nursing foal should have access to good pasture or creep feed, because the intakes of Ca, P and Cu from milk may be less than optimum to meet the daily mineral element requirements.  相似文献   
45.
氮素形态不同配比对黄瓜生长和性别分化的影响(初报)   总被引:6,自引:0,他引:6  
采用基质培养研究氮素形态不同配比对黄瓜生长及性别分化的影响,结果表明用纯NO3--N营养液处理,黄瓜植株营养生长旺盛,当NH4 -N占25%和50%时,黄瓜的生殖生长明显促进,表现为比纯NO3--N处理第一雌花低0.4、0.6节,雌花率增加了23.9%、31.0%,单株产量增加了35.3%、28.7%。叶片和果实中矿物元素钾增加了0.02%~1.41%,铁增加了11~124,ug/g DW,锌增加了37.6~47.0μg/g DW,镁、锰、铜差异不大。黄瓜在不同生育期对氮素形态的敏感性有差异,幼苗期比生长旺盛期不敏感。  相似文献   
46.
四种鲜牛肝菌成分分析   总被引:1,自引:0,他引:1  
采用原子吸收分光光度法、比色法等方法对美味牛肝菌、华美牛肝菌、美柄牛肝菌和绒柄牛肝菌4种鲜牛肝菌的粗蛋白、粗脂肪、矿质元素、有害元素的含量进行测定.结果表明,4种鲜牛肝菌中,粗蛋白、粗脂肪、总糖和粗纤维的含量范围分别是4.38%~5.42%、2.47%~3.07%、1.26%~3.85%、1.23%~1.56%;矿质元素铁、锌、钙的含量范围分别是19.62~37.96mg/kg、6.53~9.67mg/kg、146.23~298.02mg/kg;总砷含量未检出,有害元素总汞、铅、镉的含量范围分别是0.06~0.73mg/kg、0.4~0.62mg/kg、0.075~0.105mg/kg.结论:这4种野生鲜牛肝菌含有丰富的营养成分,但华美牛肝菌、美柄牛肝菌中总汞含量较高,值得关注.  相似文献   
47.
纽荷尔脐橙缺硼表现与其硼、糖含量年变化的关系   总被引:13,自引:4,他引:13  
 研究了赣南‘纽荷尔’和‘朋娜’脐橙果实及叶片的硼和可溶性糖含量的年变化。结果表明: 幼果期两品种果皮硼含量均较高, 之后果皮与果肉硼含量均趋下降, 但在果实膨大中后期均出现显著上升。纽荷尔越冬老叶硼含量趋明显下降并居较低水平, 而朋娜老叶硼含量变幅小且相对较高。果实膨大中后期两品种果皮和果肉的可溶性糖含量均与果实硼含量出现同步积累, 此时二者老叶和朋娜春梢叶的糖含量均出现低谷, 而对应纽荷尔春梢叶糖含量并无明显下降。  相似文献   
48.
用灰色系统理论的斜率关联度分析法,求得影响黑杨派南方型无性系高生长的主要气候因子依次为:降水量、极低温、极高温、蒸发量、日照时数、积温、年均温(或相至湿度)、相以湿度(或年均温)、无霜期。  相似文献   
49.
This study focuses on experimental pilot assessment of contamination of shallow groundwater systems and soil-plant transfer of trace metals under amended irrigated fields. The study approach involved a pilot experimental (greenhouse) set-up of organo-mineral amended test plots/troughs (40 cm × 47 cm × 46 cm) planted with two common vegetable crops (Amaranthus hybridus and Abelmoschus esculentus) and irrigated with wastewater. In addition to the geochemical analyses of the primary un-amended and amended soils before planting as well as residual soils after harvesting, measurements of the physico-chemical parameters and chemical analyses of trace metals concentrations in irrigation leachates and harvested vegetable tissues were also undertaken following appropriate standard sample preparation and analytical methods.The results of the geochemical analyses carried out on irrigation leachate samples collected during the sprouting stage revealed that most of the analyzed trace metals in the collected leachates exhibited 2-10 folds depletion (except for Cu and Co with enrichment of about 1.5-3 folds) compared to the initial wastewater used for irrigation. A situation attributed to uptake/bioaccumulation of these metals and selective enrichment in the residual soils as well as to leaching by infiltrating irrigation water. Nonetheless, the observed higher trace elements concentrations in the second sets of leachates collected during harvesting stage compared to the first sets of leachates collected during the sprouting/vegetative stage is an indication of higher plant uptake during sprouting/vegetative stage or initial sorption/complexation of biosolids amendment before later vertical re-mobilization by infiltrating irrigation water.Although, virtually all of the analyzed metals exhibited elevated concentrations (2-173 ppm) in both A. hybridus and A. esculentus, a closer evaluation revealed 1.2-8.2 folds enrichment of Cr, Co, Ni, Cd, Cu, and Pb in A. esculentus compared to that of A. hybridus, an indication of the fact that phyto-accumulation of trace metal is plant-specific and dependent on physiological set-up. The overall evaluation had clearly demonstrated the potential danger of bioaccumulation of toxic trace metals under biosolid amended soils as well as impacts of irrigation-induced leaching on the shallow groundwater quality, while the need to evolve a sustainable agricultural practices is also highlighted.

Capsule

Organo-mineral amendment can lead to trace metal bioaccumulation (in plants) and irrigation-induced leaching to shallow groundwater system.  相似文献   
50.
AIM: To evaluate the association between apolipoprotein E(apoE) gene polymorphism and sporadic Alzheimer's disease (AD). METHOD: A case-control study was undertaken detecting the polymorphism of apoE by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP).RESULTS:(1)The frequencies of 3/4 genotype and 4 al ele in AD were significant ly higher than that in age-matched controls(P<0.05).(2)The frequency of G/G genotype for apoE IE1 in AD was significantly higher than that in age-mat ched control(P<0.05).(3)The apoE 4 al ele was associated with a tripling of the risk for AD compared with no 4 allele(odd ratio 2.932, 95%CI 1.379~6.226);Homozygosity of the G allele in IE1 was associated with adoubling of the risk for AD compared with the G/C and C/C genotypes(odd rat io 2.223, 95%CI 1.075~4.599).However, the IE1 G al ele is also closely associated with apoE 4.When the sample was split on the basis of apo Egenotype, the associat ion between IE1 G/G genotype and AD was no longer statistically significant.CONCLUSION: ApoE ε4 was a risk factor of AD, and the apparent association between IE1 G/G and AD is a consequence of the association between the ε4 and IE1 G/G genotype.  相似文献   
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