Lunar anorthosite 15415: texture, mineralogy, and metamorphic history

Lunar anorthosite 15415 consists almost entirely of anorthite (homogeneous anorthite 96.6 molecule percent), with accessory diopsidic augite and traces of hypersthene, ilmenite, and a silica mineral. The rock has had a complex metamorphic history. The texture reflects at least two episodes of shearing (followed by intense and partial recrystallization, respectively), one episode of cataclastic deformation, and one or more episodes of shattering and fragmentation.     

Semimicro Chemical and X-ray Fluorescence Analysis of Lunar Samples

Major and selected minor elements were determined in seven whole rock fragments, five portions of pulverized lunar rock, and the lunar soil. Three different rock types were represented: vesicular, fine-grained basaltic rocks; medium to coarse-grained, vuggy gabbroic rocks; and breccia. The ranges (in percent) for the major constituents of the lunar samples are: SiO(2), 38 to 42; Al(2)O(3), 8 to 14; total iron as FeO, 15 to 20; MgO, 6 to 8; CaO, 10 to 12; Na(2)O, 0.5 to 1; K(2)0, 0.05 to 0.4; TiO(2), 8 to 13; MnO, 0.2 to 0.3; and Cr(2)O(3), 0.2 to 0.4. The high reducing capacity of the samples strongly suggests the presence of Ti(III).     

应用激光诱导击穿光谱定量分析脐橙中的金属元素

为了探讨水果中金属元素的实时快速检测方法,运用激光诱导击穿光谱(LIBS)技术对烘干的脐橙橙皮和橙肉中的金属元素Cu、Ni、Ti、Sr、Ba、Cr进行定量分析.采用1 064 nm的Nd:YAG调Q脉冲激光发生器,在同等条件下烧灼脐橙橙皮和橙肉,利用八通道光纤光谱仪对特定波长范围的光谱波段进行鉴别分析,比较烘干橙皮和橙...     

Cordierite-spinel troctolite, a new magnesium-rich lithology from the lunar highlands

A clast of spinel troctolite containing 8 percent cordierite (Mg(2)Al(4)Si(5)O(18)) has been identified among the constituents of Apollo 15 regolith breccia 15295. The cordierite and associated anorthite, forsteritic olivine, and pleonaste spinel represent a new, Mg-rich lunar highlands lithology that formed by metamorphism of an igneous spinel cumulate. The cordierite-forsterite pair in the assemblage is stable at a maximum pressure of 2.5 kilobars, equivalent to a depth of 50 kilometers, or 10 kilometers above the lunar crust-mantle boundary. The occurrence of the clast indicates that spinel cumulates are a more important constituent of the lower lunar crust than has been recognized. The rarity of cordierite-spinel troctolite among lunar rock samples suggests that it is excavated only by large impact events, such as the one that formed the adjacent Imbrium Basin.     

Particle Track, X-ray, Thermal, and Mass Spectrometric Studies of Lunar Material

Particle tracks in Apollo 11 samples are dominantly of cosmic ray and solar origin: primary galactic and solar flare particles, likely spallation recoil tracks, and possible solar-wind heavy particles. The energy spectrum of irongroup nuclei is inferred from track density gradients in surface layers, and a limit of < 10(-7) centimeter per year is deduced for the surface erosion rate. From cosmic ray tracks in rock and core samples it is clear that the lunar soil is stirred often during each few million years. X-rays reveal augite, anorthite, olivine, ilmenite, troilite, nonmeteoritic iron, and assorted glasses, but no major structural damage. Hydrogen, helium, and other gases in the fines are compatible with expected solar wind ratios.     

密云水库上游铁矿区重金属在胡敏酸中的分布特征研究

以北京市密云水库上游铁矿区为研究对象,研究了不同深度(0~20 cm和20~40 cm)土壤样品和胡敏酸中重金属的分布特征以及重金属与胡敏酸之间的相关性。根据国际腐殖质协会提供的胡敏酸提取方法从土壤样品中提取胡敏酸,使用ICP-MS测定了土壤样品和胡敏酸中重金属V、Cr、Co、Ni、Cu、Zn、Cd和Pb的含量,并使用相关性分析法和富集因子法研究了重金属和胡敏酸之间的相互关系。结果表明:土壤样品中V、Cr、Co、Ni、Cu、Zn、Cd和Pb在0~20 cm的平均含量高于20~40 cm;胡敏酸中V、Co、Ni、Cu、Zn和Pb在0~20 cm的平均含量高于20~40 cm,Cr和Cd则相反。相关性分析表明V、Cr、Co、Ni、Cu、Cd和Pb的含量与有机质含量和胡敏酸含量均表现出显著相关性,V、Co、Cu、Cr、Ni和Zn的含量与胡敏酸和有机质含量之比(HA/OM)呈负相关。富集因子分析表明胡敏酸对V、Cr、Ni、Zn和Pb的结合能力不强,而对Cu元素的结合能力很强;0~20 cm的胡敏酸对V、Cr、Co、Ni、Cu、Zn和Pb的富集程度高于20~40 cm,Cd则在20~40 cm的胡敏酸中富集程度更高。     

Al_2O_3－SiCp新型陶瓷刀具加工奥氏体不锈钢的性能研究

本文利用山东工业大学新研制的Ａｌ２Ｏ３－ＳｉＣｐ陶瓷刀具对难加工材料奥氏体不锈钢１Ｃｒ１８Ｎｉ９Ｔｉ进行了干式和湿式切削试验，并与厂家推荐的常用刀具材料ＹＧＳ进行了对比实验．结果表明，Ａ１２Ｏ３一ＳｉＣｐ陶瓷刀具的切削性能较ＹＧ８有明显提高，特别是在高速切削时．刀具磨损速度显著降低。另外，本文还对该刀具材料在不同切削条件下的切削性能进行了分析。     

Composition of the Earth

New estimates of solar composition, compared to earlier measurements, are enriched in Fe and Ca relative to Mg, Al, and Si. The Fe/Si and Ca/Al atomic ratios are 30 to 40 percent higher than chondritic values. These changes necessitate a revision in the cosmic abundances and in the composition of the nebula from which the planets accreted (which have been based on chondritic values). These new values imply that the mantle could contain about 15 weight percent FeO and more CaMgSi(2)O(6) than has been supposed. Geophysical data are consistent with a dense, FeO-rich lower mantle and a CaMgSi(2)O(6) (diopside)-rich transition region. FeO contents of 13 to 18 weight percent appear to be typical of the mantles of bodies in the inner solar system. The oldest komatiites (high-temperature MgO-rich magmas) have a similar chemistry to the derived mantle. These results favor a chemically zoned mantle.     

成都平原西缘典型水稻土壤风险元素及磷、硒来源解析与评价

为探究成都平原水稻土壤风险元素来源及其风险性,本研究以成都平原西缘某地0～20 cm的水稻土壤为研究对象,以土壤中Ni、Cr、Cu、Pb、Zn、As、Cd、Hg、P、Se这10种元素作为研究要素,借助统计学描述分析、聚类分析、主成分分析和GIS方法对10种元素的主要来源进行解析,并对其中8种重金属元素的污染风险进行评价。结果显示,研究区水稻土壤中Ni、Cr、Cu没有表现出明显的富集特征,Pb、Zn、As趋向于富集,Cd、Hg、P、Se有明显的富集现象。研究区人为活动影响较强的区域主要分布于I河至J河一带和L河沿岸地区。研究区内Cu、Cr、Ni、Se主要来源于成土母岩,Pb、As受磷石膏堆影响,Hg、P受居民生活废弃物影响,Zn、Cd受控于当地化工企业活动。研究区农耕土壤受Cd胁迫,内梅罗综合污染指数为1.20,达到轻度污染程度。     

永康城市土壤重金属污染评价及来源分析

基于浙江省永康市市域范围内7种土地利用类型的采样点共计203个,利用描述性统计分析、单因素评价分析、内梅罗综合污染指数、相关性分析、主成分分析和聚类分析等方法对研究区土壤表层重金属质量分数、污染程度和重金属相关关系及来源进行研究。结果表明:①永康市城市土壤表层重金属砷(As),钴(Co),铬(Cr),铜(Cu),锰(Mn),镍(Ni),铅(Pb),钛(Ti),钒(V),锌(Zn)的平均质量分数为6.57,10.57,119.55,22.978,528.51,22.45,37.67,5751.81,84.37,90.25 mg·kg-1;②研究区表层土壤均呈现为轻度及以上污染水平,重金属元素的平均单因素污染指数由大到小依次为铬＞镍＞钒＞钴＞钛＞铜＞锌＞锰＞铅＞砷;平均内梅罗综合污染指数由高到低排序为工业用地＞交通用地＞公园绿地＞住宅用地＞林地＞市政文教用地＞耕地。③永康市城市土壤表层中铬、铜、镍、铅、锌元素主要来源与当地的五金制造业和交通运输,砷和钒主要来源于工业与自然成土过程中的元素积累,钴和钛主要来源于五金制造业。图2表8参22     

女贞子中微量元素的分析研究

采用一种套筒电极和分段曝光新技术,在一米平面光栅摄谱测得女贞子样品中含有27种微量元素。本研究为女贞子药效提供科学依据,也给其它中草药微量元素提供一个切实可行的测试方法。     

Mineralogic and petrologic study of lunar anorthosite slide 15415,18

The anorthosite slide 15415,18 contains 98 percent subhedral plagioclase (97 mole percent anorthite), two pyroxenes: diopsidic augite (46 percent wollastonite, 39 percent enstatite, 16 percent ferrosilite) with subsidiary (100) lamellae and grains of hypersthene (2.5 percent wollastonite, 58 percent enstatite, 39.5 percent ferrosilite), and traces of ilmenite. The pyroxene occurs interstitial to, and as small grains enclosed within, plagioclase. The textures and compositions of the phases appear compatible with an origin by concentration and adcumulus growth of plagioclase from a gabbroic anorthosite (or hyperaluminous) magma in a "plutonic" environment.     

江西省水稻优势产区重金属污染及累积规律

对江西省7个水稻优势主产区的农田土壤环境质量进行监测和评价,发现该省农田土壤环境质量除部分因污水灌溉出现不同程度的重金属污染外,整体上属于清洁型,土壤环境质量适合水稻生产。分析该省50年代以来水稻田土壤中各种重金属的变异,农田土壤中铜、铅、镉和汞的含量呈现富集趋势,铬的含量变化不大,锌、镍和砷的含量出现下降趋势。运用SPSS 14.0对监测结果进行聚类分析研究,农田土壤中的镉、汞和砷等重金属主要来源于农业生产中化学投入品的大量使用,锌、铅和铬等重金属主要来源于大气中的沉降物,铜和镍的土壤含量与成土母质和矿业开采有一定关联。     

Densities of liquid silicates at high pressures

Densities of molten silicates at high pressures (up to approximately 230 kilobars) have been measured for the first time with shock-wave techniques. For a model basaltic composition (36 mole percent anorthite and 64 mole percent diopside), a bulk modulus K(s), of approximately 230 kilobars and a pressure derivative (dK(s)/dP) of approximately 4 were derived. Some implications of these results are as follows: (i) basic to ultrabasic melts become denser than olivine-and pyroxene-rich host mantle at pressures of 60 to 100 kilobars; (ii) there is a maximum depth from which basaltic melt can rise within terrestrial planetary interiors; (iii) the slopes of silicate solidi [(dT(m)/dP), where T(m) is the temperature] may become less steep at high pressures; and (iv) enriched mantle reservoirs may have developed by downward segregation of melt early in Earth history.     

几种鲚属鱼类全鱼的元素含量特征研究

以刀鲚(Coilia ectenes)、湖鲚(C.ectenes taihuensis)、凤鲚(C.mystus)和七丝鲚(C.grayii)为研究对象,对其进行元素含量特征研究。利用电感耦合等离子光谱仪(ICP-OES)测定了23种元素(Al、B、Cd、Co、Ca、Cr、Cu、Fe、K、Li、Mg、Mn、Mo、Na、Ni、P、Pb、S、Se、Sn、Sr、Ti和Zn)的含量,其中10种元素(B、Cd、Co、Cr、Li、Mo、Pb、Se、Sn和Ti)低于检出限未被检出。针对不同种类的鲚鱼全鱼所测得的元素进行多元统计分析,结果表明4组样品元素含量差异显著:主成分分析结果显示不同组的鲚鱼样品可较好地被区分,聚类分析映证了这一结论,逐步判别分析显示对全部30尾个体判别正确率为100%。元素含量特征分析结果显示,鲚属鱼类不同物种可以有效被区分。     

Lunar anorthosites: rare-Earth and other elemental abundances

Elemental abundances of major (Ti, Al, Fe, and Ca), minor (Na, Mn, and Cr), and trace elements [14 rare-earth elements (REE), Y, In, Cd, Rb, Cs, Ba, Co, and Sc] in lunar anorthosites separated from Apollo 11 sample 10085 coarse fines have been determined by means of instrumental and radiochemical neutron activation analysis. The REE distribution pattern of lunar anorthosites, relative to ordinary chondrites, has a positive Eu anomaly. On the assumption that (i) the lunar composition is similar to that of ordinary chondritic meteorites low in total Fe ( approximately 13 percent); (ii) lunar anorthosites are derived from highland cratering events and are representative of the highlands; and (iii) the moon differentiated into olivine, hypersthene, and basaltic and anorthositic phases, and plagioclase crysstallization began after approximately 93 percent solidification, then mass balance calculations yield approximately 30-kilometer and approximately 10-kilometer thicknesses for the lunar highlands for the melting and chemical differentiation of the entire moon and of the upper 200 kilometers, respectively. Corresponding thicknesses of the basaltic basement rocks were approximately 5 kilometers and approximately 2 kilometers, respectively. Alternatively, if the anorthosites of this study are representative of the highlands and the onset of plagioclase crystallization occurred after approximately 50 percent solidification of the initially melted moon, calculations with REE and Ba partition coefficients suggest that the REE and Ba abundances in the primeval moon were similar to those observed in basaltic achondrites.     

用同步辐射X-射线荧光分析法研究感病烟草单细胞内微量元素变化

用同步辐射X－射线荧光分析（SRXFA）技术分析植物单细胞的微量元素，研究病毒侵染植物后植物单原生质体内微量元素的相对变化。用果胶酶和纤维素酶分离烟草叶肉细胞原生质体，经3％戊二醛固定30min后，置于杜乐膜上，干燥后用同步辐射X－射线荧光法分析。X－射线流强大于80mA时，停留取谱时间20min,可从烟草单个原生质体中检测到Cl,Ca,Mn,Fe,Cu,Zn,Cr,Co,Ni,As,Ti和Ge。流强低于80mA时，只可检出Cl,Ca,Fe,Cu,Ti和Ge。结果表明烟草被烟草花叶病毒感染后，Ca,Fe离子的强度下降，Cl,Cu,Ge离子变化不显著。其他离子因响应值过低无法比较。     

煤矸石中几种重金属元素含量及形态变化

对抚顺西露天矿煤矸石山表层煤矸石进行多点取样,分析测定了矸石山表层煤矸石重金属Cd,Pb,Ni,Zn,Cr,Cu的含量及其形态特征。结果表明,煤矸石中Cd,Ni,Cu元素高出抚顺地区土壤环境背景值,其中Cd,Ni超出土壤环境质量2级标准。煤矸石重金属元素存在形态的分布规律总体与元素含量具有一致的变化规律,元素Cd,Pb,Ni,Zn,Cr,Cu的赋存形态普遍以残渣态、可还原态为主,可氧化态次之,弱酸可提取态比例最低。     

Writing, dictating, and speaking letters

It is commonly assumed that dictation requires a long time to learn, but authors eventually dictate much faster than they write. Performance results now show that novice dictators can learn in a few hours to dictate with the speed and quality with which they write. However, they do not think they perform this well. Dictators with years of experience are from 0 to 25 percent faster than novices, depending upon the complexity of the letters. Planning time is about two-thirds of composition time, regardless of the method of composition.     

汞·铬和镍对唐鱼的急性毒性及安全浓度评价

[目的]研究唐鱼对汞（Hg）、铬（Cr）和镍（M）3种重金属的致毒敏感度和安全质量浓度。[方法]采用静水法测试唐鱼对Hg、Cr和Ni重金属溶液的半致死浓度,并评价水环境Hg、Cr和Ni对鱼类的影响。[结果]Hg、Cr和Ni对唐鱼不同时间的半致死质量浓度曲线表明,Hg对唐鱼为剧毒物质,Nj为中毒物质,Cr为低毒物质。3种重金属的毒性依次为Hg〉Ni〉Cr。Hg、Ni和Cr对唐鱼的24、48、72、96h的LC50分别为0．105、0．092、0．084、0．075mg／L,36．230、21．960、13．780、9．268mg／L,84．030、72．260、65．210、55．960mg／L,其安全质量浓度分别为0．008、0．927、5．596mg／L。[结论]唐鱼对这3种重金属的耐受性较高;各种重金属离子共存时可能对唐鱼存在某种协同或拮抗作用,温度、溶解氧等理化因子的改变对重金属的毒性也有影响,还影响LC50值。