Chemical composition and antioxidant activity of certain <Emphasis Type="Italic">Morus</Emphasis> species

In the present work, the fruits of four Morus species, namely Morus alba (white mulberry), Morus nigra (black mulberry), Morus laevigata (large white fruit), and Morus laevigata (large black fruit), were analyzed for proximate composition, essential minerals, and antioxidant potentials. For this purpose, the ripe fruits were collected from the northern regions of Pakistan. The major nutritional components (moisture, ash, lipids, proteins, fibres, carbohydrates, and total sugar) were found to be in the suitable range along with good computed energy. Total dry weight, pH, and titratable acidity (percent citric acid) were (17.60±1.94)–(21.97±2.34) mg/100 g, (3.20±0.07)–(4.78±0.15), and (0.84±0.40)%–(2.00±0.08)%, respectively. Low riboflavin (vitamin B₂) and niacin (vitamin B₃) contents were recorded in all the fruits, while ascorbic acid (vitamin C) was in the range from (15.20±1.25) to (17.03±1.71) mg/100 g fresh weight (FW). The mulberry fruits were rich with regard to the total phenol and alkaloid contents, having values of (880±7.20)–(1650±12.25) mg/100 g FW and (390±3.22)–(660±5.25) mg/100 g FW, respectively. Sufficient quantities of essential macro-(K, Ca, Mg, and Na) and micro-(Fe, Zn, and Ni) elements were found in all the fruits. K was the predominant element with concentration ranging from (1270±9.36) to (1731±11.50) mg/100 g, while Ca, Na, and Mg contents were (440±3.21)–(576±7.37), (260±3.86)–(280±3.50), and (240±3.51)–(360±4.20) mg/100 g, respectivly. The decreasing order of micro-minerals was Fe>Zn>Ni. The radical scavenging activity of methanolic extract of fruits was concentration-dependent and showed a correlation with total phenolic constituents of the respective fruits. Based on the results obtained, mulberry fruits were found to serve as a potential source of food diet and natural antioxidants.     

工业废水对隆线溞的毒性研究

采用理化和生物监测相结合的方法研究工业废水的毒性,研究结果表明,从理化指标可以看出取自长泰县五处工业排放的污水基本符合国家标准,但是通过隆线溞(Daphnia carinata,Dc42)作为生物监测器检测的结果表明,除一处排出水没有毒性之外,其他四处排出的废水均有不同程度的毒性,说明工业废水在理化指标检测合格之后依然存在着潜在的毒性。可见同时利用理化指标和生物毒性试验来监测工业废水结果更为准确、可靠。     

十七省市奶粉中26种矿质元素的测定

作者收集了国内17个省市(自治区)的18个乳品生产厂家的全脂奶粉。用六种方法测定奶粉中的铁、锰、锌、钴、钼、铬、镍、矾、锡、氟、硒、硅、砷、钠、钾钙、磷、镁、铝、硼、钴、镉、钡、铅、锶和汞等26种矿质元素的含量。并对所获得的数据进行了初步的分析与讨论。     

云南石林县药用植物资源调查研究

经过5a多的调查并结合采集的5000余份标本的鉴定,以及查阅相关文献资料进行分析研究,首次报道了云南省石林县药用植物资源中的38个科84属和110个种（含变种）．同时,讨论了药用植物的海拔、生境、药用部位、主要化学成分及其功效等内容,探讨了重要植物的药用功能以及如何保护这些植物资源．     

泉州市售牛奶中抗生素残留的分析

为了解和比较泉州市市售生牛奶及消毒纯牛奶中抗生素残留情况，从泉州市不同区域及两个奶牛场采集生牛奶150份．几大超市采购消毒纯牛奶100份．按国家标准GB／T4789．27-2003，采用TTC法进行检测，检测出生牛奶中阳性27份，可疑15份，阳性率18％，可疑率10％；国产消毒纯牛奶75份，阳性14份，阳性率18．7％；进口纯牛奶25份，阳性0份，阳性率0％，调查结果显示，本市产的生牛奶中抗生素残留阳性率比国产消毒纯牛奶高，牛奶中抗生素残留的情况仍较为严重，应引起广大消费者的注意，并倡议政府部门应加强对食品安全的管理和执行力度，以尽快改善此现状。     

长期施用含硫化肥对水稻土化学性质和水稻吸收微量元素的影响

已持续26年的湖南祁阳红壤站长期肥料试验分三个处理:NH4C1 KCl KH2PO4;尿素 KCl 过磷酸钙;(NH4)2SO4 K2SO4 过磷酸钙.其土壤、水稻植株样品被用来研究长期施用含硫化肥对水稻土酸化、SO42--S在土壤中累积、土壤-水稻系统微量元素含量和水稻产量的影响.结果表明:大量(667 kg S hm-2yr-1)施用含硫化肥15年后已导致水稻土表层土壤pH明显下降.不施硫处理SO42--S逐年下降,而施硫处理SO42--S有明显累积.施用含硫化肥24年后(1998),土壤有效Cu、B、Mn及全Ca含量有增加趋势,全Fe有减少趋势,对有效Mo、Zn及总Mg似乎没有影响.长期施用含硫化肥已显著减少水稻(特别是晚稻)吸收Fe、Mo、B、Mg、Cl,并导致水稻(特别是晚稻)产量显著下降.可见,长期施用含硫化肥可能影响水稻土性质进而影响水稻生长.     

不同做青风格安溪铁观音“音韵”的感官审评及品质化学比较

为探讨安溪铁观音＂音韵＂的感官品质及其化学特征,对3种不同做青风格的安溪铁观音样品进行感官审评,并对其主要品质成分进行常规测定与高效液相色谱法（HPLC）测定。结果表明：＂正做型＂铁观音,其酯型儿茶素总量较高、游离氨基酸总量较低、酚氨比较高,其外形乌润紧结、香气幽长沉香、汤色金黄明亮、滋味醇厚高爽、叶底金黄肥软,＂音韵＂醇而幽长;＂消青型＂铁观音,其游离氨基酸总量较中等、酯型儿茶素总量中等、酚氨比中等,其外形翠绿圆结、香气浓郁鲜香、汤色黄绿明亮、滋味鲜爽甘甜、叶底绿黄软亮,＂音韵＂厚而鲜爽;＂拖酸型＂铁观音,其游离氨基酸总量较高、酯型儿茶素总量较低、酚氨比较低,其外形乌绿润圆结、香气高锐鲜酸、汤色杏黄明亮、滋味鲜酸甘爽、青绿微暗,＂音韵＂锐而鲜爽。因此,这3种不同做青风格的铁观音,其外形和内质都有较为典型的品质特征,可以适应茶叶市场上不同消费人群的需求。     

环保型铝合金表面无铬化学转化膜的制备及其性能

室温下,以Ti（S04）22-6g／L,H2021-2g／L,NaF3-5g／L,EDTA2-6g／L为转化液的主要成分,加入1-2g／LCe（N03）3 ．6H20促进转化膜的致密性和均匀性,控制转化液pH4．0-4．5,转化处理10min,在样品表面制备一层化学转化膜．通过中性盐雾测试和电化学测试表征转化膜的耐蚀性,采用冷场发射扫描电镜（SEM）观察转化膜的微观形貌,X射线能谱仪（EDS）分析转化膜的化学成分．结果表明：该转化膜耐蚀性优艮,EDS能谱分析得出这层颗粒状物质主要由Na,A1,F元素和少量的Mg,Ti,O元素组成,推断转化膜的主要成分为Na3AIF6,铈盐起到促进转化膜致密性和均匀性的作用．     

ICP-AES测定木香薷中4种宏量金属元素的含量

为研究木香薷中人体必需的宏量金属元素含量状况,用微波消解法消解样品,用电感耦合等离子体-原子发射光谱法（ICP-AES）测定了木香薷叶、茎、花序样品中4种宏量金属元素（Ca、K、Mg、Na）的含量.结果表明：各测试元素校准曲线的相关系数均为0.999 8~0.999 9,显示其良好的线性;测定的RSD值均在0.36%～2.22%之间,显示了较高的测定精密度;木香薷叶、茎、花序三个部位中各元素含量相比,花序中的K与Na含量最高,分别为19.98 g/kg与0.27 g/kg,而叶中是Ca与Mg的含量最高,分别为22.33 g/kg与2.80 g/kg,茎中Ca、K与Mg的含量均居中,Na的含量最低,仅为0.09 g/kg.木香薷叶、茎、花序中4种人体必需的宏量金属元素含量丰富,但种类和数量因部位不同而异.应分不同部位对木香薷进行开发利用较为合理.     

Use of fluorometry for determination of skim milk powder adulteration in fresh milk

INTRODUCTION Adulteration of fresh milk by adding reconsti- tuted milk or the selling of reconstituted milk as the fresh product can be economically advantageous when either a surplus of milk powder exists or in countries where the importation of dried milk powder is subsidized. Adulteration malpractice creates unfair competition, could lead to market distortions, which in turn may impact the local or even the international economy. When legislation prohibits such practice, the detection o…     

核心素养下的体育教学渗透德育策略刍论

将德育与体育二者相融合、渗透,已成为体育教学中创新性较强、教学效率较高的实践方向之一。教师要进行综合调研与科学评估,把握学生的阶段特征与学习需求;对接课程标准,帮助学生树立正确的发展与价值观念;探索教学方式创新,为体育教学注入新鲜活力;优化评估方式,设计科学的综合性评估标准。     

火焰原子吸收法测定柳树种子中的矿质元素

用火焰原子吸收法测定了柳树种子中的Ca、Zn、Fe、Cu、K、Na、Co、Ni、Mn、Cr、Mg等微量元素,为柳树种子资源的开发提供了依据.各元素的回收率在92%～105%.结果表明,柳树种子富含人体所需的微量元素及大量元素.     

牛蒡子的形态与组分

对牛蒡子形态特征及营养成分进行了测定,以期为牛蒡子的鉴别、贮藏及开发利用提供基础资料.结果表明：①牛蒡子为瘦果,长倒卵形,灰褐色,带黑色斑点,有数条纵棱.果实长×宽×厚为6.04 mm ×2.68mm×1.52 mm,单粒质量为13.48 mg.②牛蒡子果皮坚硬,内含种子1枚,为双子叶无胚乳种子.③牛蒡子中蛋白质的质量分数为131 mg/g;可溶性糖的质量分数为44.7 mg/g;粗脂肪的质量分数为39.1 mg/g;还含有K,Ca,Mg,Na,Fe,Mn,Zn,Cu等矿质元素,且K,Ca,Mg,Na的含量明显高于其它矿质元素.④牛蒡子种子发芽率为96％,在28℃恒温箱中约需5d便可萌发,为子叶出土幼苗.     

Partial least squares regression for predicting economic loss of vegetables caused by acid rain

To predict the economic loss of crops caused by acid rain, we used partial least squares （PLS） regression to build a model of single dependent variable - the economic loss calculated with the decrease in yield related to the pH value and levels of Ca^2＋, NH4^＋, Na^＋, K^＋, Mg^2＋, SO4^2-, NO3^-, and Cl^- in acid rain. We selected vegetables which were sensitive to acid rain as the sample crops, and collected 12 groups of data, of which 8 groups were used for modeling and 4 groups for testing. Using the cross validation method to evaluate the performace of this prediction model indicates that the optimum number of principal components was 3, determined by the minimum of prediction residual error sum of squares, and the prediction error of the regression equation ranges from -2.25% to 4.32%. The model predicted that the economic loss of vegetables from acid rain is negatively corrrelated to pH and the concentrations of NH4^＋, SO4^2-, NO3^-, and Cl^- in the rain, and positively correlated to the concentrations of Ca^2＋, Na^＋, K^＋ and Mg^2＋. The precision of the model may be improved if the non-linearity of original data is addressed.     

云南烤烟评吸质量与化学成分的关系研究

分析云南烤烟总糖、还原糖、总氮、烟碱等化学成分的含量,并对香气质、香气量、浓度、余味等评吸质量进行专家评吸打分。化学成分与评吸质量的相关分析表明,与评吸质量关系密切的化学成分主要为糖组分和含氮化合物。香气质、香气量、评吸总得分与化学成分的逐步回归分析表明,化学成分对香气质作用的大小为:挥发碱>总糖>总氮>总灰分,对香气量作用的大小为:总灰分>总糖,对总体评吸质量的作用大小为:总糖>总氮>总灰分>蛋白质>还原糖>钾。     

云南高原引种津巴布韦烤烟资源的评价

采用严格的田间小区品比试验对5个津巴布韦引进烤烟品种（系）和2个对照取样,对其9项重要化学成分进行检测．通过对比分析表明：津引烤娴资源的化学成分与K326相比,呈现“两糖低、烟碱低、氧化钾高”的三大显著特征;与云烟87相比,呈现“两糖低、淀粉低、氧化钾高、石油醚提取物高”的四大显著特征;在云南高原种植条件下,津引良种的烟叶氧化钾含量（质量分数）超过2％,石油醚提取物含量超过5％,总糖、还原糖分别低于31％和26％,淀粉含量低于3％和上部叶的烟碱含量低于2．5％．这说明,云南现有种植品种与津引品种有差异明显,在云南种植津巴布韦品种可以生产出类似津巴布韦的优质烟叶．     

海产和淡水养殖南美白对虾肌肉中无机元素的含量比较

应用石墨炉和火焰原子吸收光谱法,对海产和淡水养殖南美白对虾中的13种无机元素进行了比较分析;探讨了基体改进剂对实验效果的影响及仪器工作的最佳条件;实验结果表明,海产和淡水产虾体中均未测出Co;Pb、Cd含量均低于国家水产品卫生标准;除Na外,淡水养殖南美白对虾中K、Ca、Mg、Fe、Cu的含量均高于海产．两者虾体中Zn、Cr、Mn、Ni的含量相当,火焰法的回收率为90．67—109．00％,RSD≤2．21;石墨炉法回收率为90．50—107．45％,RSD≤3．67（n=3）．     

火焰原子吸收法测定秦巴山区茶叶中微量硒

用火焰原子吸收光谱法测定了秦巴山区茶叶中微量硒的含量,用HNO3-HClO4为茶叶的分解试剂,湿法硝化分解茶叶,以Ni(NO3)2为基体改进剂,排除Fe、Mg、Na、K、SO42-等的干扰,使吸收信号达到稳定,硒浓度在0～40mg/L范围内呈良好线性关系.     

RETRACTED ARTICLE: Synthesis of hydroxylated and methoxylated polybrominated diphenyl ethers

Hydroxylated/methoxylated polybrominated diphenyl ethers (OH/MeO-PBDEs) are not only detected as natural products, but also regarded as metabolites formed from polybrominated diphenyl ethers (PBDEs), which are widely used as flame-retardants in various materials. The aim of the present study was to synthesize authentic OH-PBDEs and MeO-PBDEs, as reference standards for environmental exploration. Twenty OH-PBDEs and their corresponding MeO-PBDEs containing three to six bromine atoms were synthesized via a trial of reactions including coupling, oxidation, bromination, methylation, etc. The products were characterized by GC-MS and 1H-NMR spectroscopy in the work. As results show, all compounds synthesized were up to 99% on purity and be reqarded as authentic standards for detecting the chemical pollutants in the emvironment.     

不同类型土质对强筋小麦品质和产量的影响

对商丘10种不同类型土质对强筋小麦品质与产量的影响进行了池栽试验,结果表明：在同一自然条件下,小麦籽粒产量与土质类型本身属性关系不大,土壤基础肥力和全氮含量对小麦籽粒产量影响较大,速效氮和全氮含量与小麦品质呈显著正相关．5种达到二级强筋小麦品质标准的土壤基础肥力是：有机质11 4．4g／kg、全氮（N）08．5 g／kg、速效氮（N）913．mg／kg、速效磷（P）92．4mg／kg、速效钾913．2 mg／kg ．