煤烟对食物、饮水氟污染的研究

测定了云南滇东“燃煤污染型”氟病区新、陈玉米(皮、饭)、饮用水(自然井水、泉水、室内缸水、开水)的含氟量，并对玉米、豆娄、辣椒进行水洗脱氟试验，结果证明由于用煤方式不当，造成室内食物、饮水的污染，发生氟中毒。     

用植物叶片中重金属元素含量指示大气污染的研究

通过对潮州市区交通繁忙路段和对照区 (红山森林公园 )不同植物叶片重金属元素 (Pb、Cd、Cu、Zn)的含量研究 ,探讨了重金属含量与城市大气污染之间的关系。结果表明 ,植物叶片中的重金属元素富积量和大气中污染指数正相关。植物叶片的重金属元素富积量可较好和客观地指示市区大气的重金属污染状况。该研究为城市规划和环境保护提供了科学依据     

煤中氟化物分布与赋存特性研究

氟是煤中微量有害元素之一 ,烟煤中含量一般为 1 0 0～ 30 0 μｇ ｇ[1 ] 。煤在燃烧时 ,煤中的氟化物将发生分解 ,大部分以ＨＦ、ＳｉＦ4等气态污染物形式排入大气 ,不仅严重腐蚀锅炉和烟气净化设备 ,而且造成大气氟污染和生态环境的破坏[2～ 4] 。燃煤污染物中 ,氟化物对动、植物的危害严重 ,给农牧业造成了重大的经济损失[4,5] 。我国是世界上唯一以煤为主要能源的大国 ,煤的主要利用形式是燃烧。燃煤引起的氟排放是大气氟污染的主要污染源。我国已将煤烟型大气氟污染列入气体检测对象 ,并制定了排放标准。因此 ,对煤中氟的赋存特性、燃…     

正离子光固化聚硅氧烷的合成及其环氧树脂复合固化膜的性能

以含氢聚硅氧烷(PMHS)分别与甲基丙烯酸六氟丁酯(HFMA)和烯丙基缩水甘油醚(AGE),经氯铂酸催化硅氢加成反应将甲基丙烯酸六氟丁酯和烯丙基缩水甘油醚引入聚硅氧烷的侧链,合成了3种含氟量不同的含氟代烃侧基/环氧侧基聚硅氧烷(EFPS),用FTIR、1H-NMR和13C-NMR进行了结构表征,将这类聚硅氧烷与环氧树脂...     

氟离子选择性电极测定沉淀磷酸钙中的氟

沉淀磷酸钙的主要成份是CaHPO_4·2H_2O,除用作肥料外,并可加入饲料中,促进牲畜发育生长。但如其含氟量高则将引起中毒及病害,故检验沉淀磷酸钙质量时含氟量是需控制的指标之一。用蒸馏法分离并用比色或容量法测定的方法繁杂费时,用电极法测定磷肥中的氟简易快速。我们试用自制的HDF电极测定沉淀磷酸钙中的氟,操作较原有分析方法简便,分析结果与蒸馏法一致。现将分析方     

离子选择性电极测定埋弧自动、半自动与电渣焊剂中的氟

埋弧自动焊、半自动焊和电渣焊接所用焊剂含氟量甚高,氟含量分析是焊剂分析中的主要项目之一。目前国内尚无焊剂标样,现有的分析方法因需反复热解或蒸馏,操作繁杂,需时冗长,分析结果重现性差。本文用氟离子选择电极测定焊剂中的氟含量。为了使试液中氟全部释放出来,维持测定过程中离子强度恒定,考察了该实验条件下,总离子强度缓冲剂(TISAB)用量对测定结果的影响。实验表明,TISAB加入量达到20毫升/50毫升,电位值基本上维持不变,即氟已全部放出,离子强度恒定。考虑到试     

人体内的氟

成年人体内氟约为２－９ｇ，比锌略多，仅次于硅和铁。人体内的氟含量由于受铝、钙、镁等元素的影响而有所波动。但是，从满足人体对氟的需要到由于过多而导致中毒的量之间相差不多。因此，氟对人体的安全范围比其他元素要窄得多。正因为这样，就更要注意自然界、饮水及食物中氟含量对人体健康的影响，尤其是工业排放的氟对环境的污染给人带来的危害。氟的生理需要量为０－５～１ｍｇ／ｄ。氟在人体中的分布主要集中在骨骼、牙齿、指甲和毛发中，尤以牙釉质中含量最多，骨骼中以长骨的含氟量最多。依次为股骨＞肱骨＞掌骨＞颅骨＞腰椎。男人…     

缺氟易患龋齿病

牙齿和骨骼的主要成分是羟磷灰石 ,氟离子与羟磷灰石有较大的亲和力 ,而且能把羟磷灰石中的羟基取代出来。含氟的磷灰石更坚实 ,而且难溶于酸。通常 ,口腔中的细菌能使残留在口腔中的糖发酵变成酸 ,这种酸能把羟磷灰石慢慢溶解 ,从而使珐琅质脱落 ,这就是常说的虫牙 ,医学上称为龋齿病。含氟的珐琅质对酸的腐蚀有抵抗力 ,不仅可避免患龋齿病 ,而且不会因为慢慢溶解而引起老年性骨疏松症。所以 ,医疗上也往往用氟化亚锡修补被蛀的牙齿。正常成年人牙齿的含氟量为每百克牙齿含氟 11ｍｇ ,骨骼中的含氟量随年龄而增长 ,人到 50岁 ,骨骼中含氟量…     

氟元素与人体健康

氟元素是人体必需微量元素，在人体内主要分布于骨骼和牙齿中。氟通过各种途径对人体发生作用。人体内少量的氟对于生长发育，骨骼代谢等有一定的影响，而含氟量过量或过少会引起某些疾病，并且氟的特性对于人体健康也有影响。     

低浓度氟的测定——直接电位法几种测量技术的比较

防治龋齿在国内外日益受到重视。为适应预防龋齿研究中测定含氟量为0.0Xppm的HClO_4浸牙液,本文介绍一种新的总离子强度调节液(TISAB),以六次甲基四胺作为pH缓冲液,以KNO_3调节离子强度,氟离子选择电极的能斯特响应下限至0.02ppm。结合采用pH4.3的HCl作为电极的清洗液,测定的结果稳定重现。测定含氟量为0.X-Xppm的茶水及饮用水     

丹皮道地产区环境地球化学特征研究

对丹皮道地产区土壤地球化学特征进行了系统研究,通过丹皮产区土壤的测试分析,将其与安徽省土壤背景值比较,摸清了丹皮道地药材产区土壤的元素本底特征.结果表明,该产区多数元素明显高于全省土壤背景值,有机质、硼元素低于全省土壤背景值.丹皮的长势和品质与其地质地球化学背景有着密切的关系;母岩类型不同,土壤地球化学成分存在较大的差...     

洛阳牡丹花中营养元素和有害元素含量分析

为了提供洛阳牡丹花能否作为蔬菜食用的科学依据,采用原子吸收法测定了洛阳红、胡红、凤丹3个品种的牡丹花中钙、铁、锰、锌、铜、铅、镉元素含量。结果表明,洛阳红、胡红、凤丹花中含有丰富的营养元素钙、锰、铁;金属元素铜、锌含量在国家食品卫生限量标准内,有害元素铅、镉含量超出了国家限量标准。从微量元素含量的角度来评价,食用洛阳红、胡红、凤丹牡丹花,存在对人体健康产生危害的风险。测定结果的RSD为0.07%～16.1%,精密度高,可靠。     

Chemical profiling and marker characterization of Huangqin decoction prepared with three types of peony root by liquid chromatography with electrospray ionization mass spectrometry

Clarification of the quality and biological effect equivalence of traditional Chinese medicines containing multi‐origin species is essential to improve their current quality standards, and also is the core problem to clarify the origins of single herbs with multi‐species in Chinese formulas that will guarantee their clinical application. Huangqin decoction is the typical one of multi‐origin formulas frequently used in traditional Chinese medicine and Kampo medicine. An ultra high performance liquid chromatography with electrospray ionization–tandem mass spectrometry was developed for chemical profiling and marker quantification of Huangqin decoction prepared with two different original types of peony root, white and red peony root. Forty‐seven main peaks in chemical profiling of Huangqin decoction prepared with white and red peony root were identified: nine were from peony root, 20 from baical skullcap root, 17 from licorice root, and one from jujubae fruit. The markers characteristics of the respective types of peony root in Huangqin decoction differ from that in single herbs, especially in terms of monoterpenoids and hydrolysable tannins. Subsequently, 17 representative markers in Huangqin decoction prepared with three types of peony root and their chemical characteristics and content distribution were carried out.     

Could gingko foliage serve as a bio-monitor for organochlorine pesticides in air?

The feasibility of gingko (Gingo Biloba) foliage as a passive bio-monitor for organochlorine pesticides in air was explored. The accumulation patterns of hexachlorocyclohexanes (HCHs), dichlorodiphenyl- trichloroethanes (DDTs) and hexachlorobenzene (HCB) in gingko foliage were similar; the amounts of HCHs, DDTs and HCB increased with foliage growth in spring and decreased thereafter. This accumu-lation pattern is likely related to the growing process of the gingko foliage, which was observed for the first time in our work, giving a piece of evidence for the "bud burst effect" in plants. Compared with those in pine needles in 1980's, the residual levels of HCHs and DDTs have declined obviously in Bei-jing, indicating that the ban on the production and use of organochlorine pesticides (OCPs) in our country is effective; however, the amount of HCB has increased, indicating great progress of chemical industry in Beijing. The analysis for the source of OCPs in the gingko foliage showed that the technical HCHs and DDTs were used largely in history, but were not used in recent years. A little lidane has been used and there was a new input of o,p′-DDT in recent years; dicofol usage may be the main source of o,p′-DDT. Concentrations of HCHs, DDTs and HCB in gingko foliages were similar to those in pine nee-dles in the corresponding period and there is a strong positive correlation between the OCPs concen-tration data obtained from these two kinds of trees. It presents no difference in the accumulation style between these two kinds of trees. The level of OCPs in the gingko foliage reflects the pollution status of OCP in air. The result of this work shows that the gingko foliage can be used as a bio-monitor of OCPs in air.     

The Optimization of Extraction Process,Antioxidant, Whitening and Antibacterial Effects of Fengdan Peony Flavonoids

Flavonoids have important biological activities, such as anti-inflammatory, antibacterial, antioxidant and whitening, which is a potential functional food raw material. However, the biological activity of Fengdan peony flavonoid is not particularly clear. Therefore, in this study, the peony flavonoid was extracted from Fengdan peony seed meal, and the antioxidant, antibacterial and whitening activities of the peony flavonoid were explored. The optimal extraction conditions were methanol concentration of 90%, solid-to-liquid ratio of 1:35 g:mL, temperature of 55 °C and time of 80 min; under these conditions, the yield of Fengdan peony flavonoid could reach 1.205 ± 0.019% (the ratio of the dry mass of rutin to the dry mass of peony seed meal). The clearance of Fengdan peony total flavonoids to 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical, hydroxyl radical and 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical could reach 75%, 70% and 97%, respectively. Fengdan peony flavonoid could inhibit the growth of the Gram-positive bacteria. The minimal inhibitory concentrations (MICs) of Fengdan peony flavonoid on S. aureus, B. anthracis, B. subtilis and C. perfringens were 0.0293 mg/mL, 0.1172 mg/mL, 0.2344 mg/mL and 7.500 mg/mL, respectively. The inhibition rate of Fengdan peony flavonoid on tyrosinase was 8.53–81.08%. This study intensely illustrated that the antioxidant, whitening and antibacterial activity of Fengdan peony total flavonoids were significant. Fengdan peony total flavonoids have a great possibility of being used as functional food materials.     

低头-头链含量的聚偏氟乙烯合成

研究了偏氟乙烯的聚合条件与其聚合物的头-头链含量的关系。实验表明聚合物的头-头链的含量与聚合温度有关,而与引发剂的种类无关。因而,可以在较低的聚合温度下聚合制得带有低的头-头结构(约3％)的聚偏氟乙烯。将聚合物链的A结构含量对其熔点作图,得一直线,可表示为方程式A=24.8+0.362T_m(％)。     

电感耦合等离子体原子发射光谱法测定紫斑牡丹胚乳和胚中矿物质元素

为了给离体体细胞胚的人工胚乳配制提供矿物质元素种类和数量方面的参考,用浓硝酸-高氯酸(4∶1)的混合溶液消解紫斑牡丹的胚乳和胚样品,采用电感耦合等离子体-原子发射光谱法(ICP-AES)测定了样品中的(K、Na、Ca、Mg、Fe、Cu、Zn、Mn、Li、Ni、B、Ag、Cd、Pb)14种矿物质元素含量。结果表明:各元素的校准曲线的回归系数在0.9990～0.9999之间,线性良好;方法精密度高,能多元素同时分析;紫斑牡丹胚乳和胚中均含有植物生长必需的K、Ca、Mg 3种大量元素,Fe、Mn、Cu、Zn、Ni、B 6种微量元素,1种有益元素Na,及Li和Pb,Ag、Cd则未被检测到。在被检测到的12种元素中,Mg、Zn、Mn、Fe、K、Na、Li与Ni 8种元素在胚乳中的含量低于胚中的含量,Ca、Cu、Pb与B在胚乳中的含量则高于胚中的含量。     

Tea and fluorosis

Tea trees (Camellia sinensis), abundant in fluoride, selectively absorb F from the soil and air in the surrounding, and accumulate mainly in the tea leaves in the form of Al and F complex. Long-term consumption of high fluoride tea could result in chronic fluoride intoxication. This review summarized those data of the fluoride content in various tea commodities, and estimated the risk of fluorosis caused by high fluoride tea commodities. We also introduced fluorosis caused by tea from case reports, epidemiology observations and animal models. Fluorosis was easily misdiagnosed and over-looked and people made little acquaintance in the high fluoride in some tea commodities. So it is the time to pay more attentions on the over-looked safety problem of tea and tea products and some measures should be taken to the fluorosis caused by tea. Large-scale epidemiological investigations and further studies on tea-type fluorosis are in need for those tea-drinking areas. In addition, it is urgent that governmental and international agencies adopt safe standards of fluoride content in tea commodities.     

A review on activation analysis of air particulate matter

A review is presented on the use of various activation analysis methods for the determination of trace elements in air particulate and related matters. A discussion is given on the contribution of such methods in solving the problem of air pollution in various parts of the world. This work is a part of a program undertaken by this Department for the evaluation of the various analytical techniques as investigative tools in pollution and other environmental studies.