STUDY ON TRANSPORT AND SEPARATION OF MO(Ⅵ) ION BY USING ELM OF TOA-SPAN 80-OXYLENE

A new ELM was prepared for the study on transport of Mo(Ⅵ) ion. Under the experimental conditions, Mo(Ⅵ) can be transported completely and separated from the co-lons.The emulsion liquid membrane(ELM) with Tri-n-octylamine(TOA) as a carrier used for the transport of Mo(Ⅵ) ions and its separation from some cations have been reported in this paper. The transport percentage of Mo(Ⅵ) ion through ELM in 5 min corresponds to that of the literature in 165 min.     

STUDY ON CHEMICAL COMPOSITIONS OF 19 L AND LL CHONDRITES AND ITS APPLICATION IN TAXONOMY

Reported in this paper are precise INAA data on 19 L and LL chondrites (7 Chinese chondrites and 12 from other countries). The L and LL chondrite data normalized to Mg and to CI chondrite indicate that for several lithophiles (V, Al, Cr and Mn), the extent of scatter is low, similar to that observed in carbonaceous chondrites. The average concentration of siderophiles in the LL group is lower than that in the L group.On the basis of olivine composition and atomic ratio (Ir/Au), we reclassify the five previously labeled L ehondrites as LL members. The atomic ratios of Ir/Au in the LL chondrites are lower than those in the L chondrites (the division is set at an Ir/Au ratio of 2.5). The atomic ratio of Ir/Au appears to be a useful classification parameter for ordinary chondrites. Therefore, it can be considered as a new taxonomic parameter. Of the elements studied, Br, a high volatile, seems most likely to show thermometamorphic effects, depending on petrologic types. The concentration of bromine and the     

THE CALCULATION OF CHEMICAL SHIFTS IN DISUBSTITUTED NAPHTHALENES

<正> The principle and method for calculating the chemical shifts of substituted benzenes have been extended to the calculation of chemical shifts in disubstituted naphthalenes. We have set up a series of empirical parameters for the calculation of chemical shifts. The calculated results of 439 8 values from 78 compounds show that the standard deviation between the calculated and the experimental values is 0.08 ppm. The combination of this calculation with that of the coupling constants can be used to provide a criterion .for the determination of molecular structure in disubstituted naphthalenes as well as to assign NMR parameters for the experiment of proton simulated spectra of disubstituted naphthalenes.     

STUDIES ON ION IMPLANTATION AND ELECTRICAL PROPERTIES OF POLYACETYLENE FILMS

The effects of ion implantation on ployacetylene films PA have been studied with Ar~+, Fe~+, C1~+, I~+, Na~+ and K~+ ions in the energy range of 15—30 keV. The changes of PA films in the electrical conductivity, due to chemical doping and ion implantation in relation to their structure and depth profiles of impurities, were measured through infrared (ATR/FTIK), Rutherford backscattering spectrometry (RBS) and the four probe technique. In all cases, ion implantation of active ions exhibits the same effects as chemical doping. The formation of p-n junction is observed at the interface of implanted region and chemical doped PA substrate. The mechanism of interaction process between ion beam and polymer is also discussed.     

RULE OF DISTRIBUTION OF PHASE POINTS OF POLY-UNIT MOLECULES AND HOMOLOGOUS LINEAR LAW

The chain M-(A)_n-N or ring obtained by bonding n number of A's with the same chemical structure in the same way is called the poly-unit molecule. Jiang Mingqian has discovered the famous homologous linear law for the poly-unit chain. Xu Guangxian and Li Lemin have studied its quantum-chemical basis and put forward the new linear factor.In order to study further the basic quantum chemistry of the homologous linear law, it is necessary to have first a thorough knowledge of the orbital characteristics of the polyunit molecules. The author studied the orbitals and the energy levels of poly-unit molecules by using difference equations. Based on the past work the concept of phase points of orbital was established, and the rule of distribution of phase points was developed as well. It is found that the phase points of similar orbitals in the molecules of a homologous series appear to condense around a certain point. Based on this fact a theoretical proof of the homologous linear law was made.     

STUDIES ON SYNTHESIS AND CHARACTER OF INORGANIC ION EXCHANGER TITANIUM PHOSPHATE—AMMONIUM TUNGSTOPHOSPHATE

In this paper,a new complex inorganic ion exchanger Titanium Phosphate-Ammonium Tungstophosphate(abbreviated as Tip-AWP) was synthesized,whose exchange character and chemical structure were studied.This compound exhibits high exchange capacity and selectivity for Cs^+,its exchange capacity accains 0.95 mmol/g in the medium of 0.1mol/L HNO3,and which almost doesn′t change in the 1AW imitated waste solution.There are no change in exchange capacity and structute after several times of exchanging,eluting,regenerating,which is of great importance to the separation and uptaking of radio-nuclides.Further more,this exchanger has good thermal and redioactive stability.     

DISCOVERY OF EARLY CAMBRIAN RADIO-LARIA AND ITS SIGNIFICANCE

The well-preserved bivalved microfossils collected from the Lower Cambrian limestone at theXiaoyang section in Zhenba, Shaanxi, have proved the oldest known radiolarians by meansof the electron probing analysis and morphological study under the electron scanning miroscopeand the observation of the thin section. The present discovery has shaken the theory thatThaeodaria originated from Spumellaria. Unlike the Mesozoic and Cenozoic radiolarians that areplanktonic, the Cambrian ones lived as benthos. On the basis of the chemical composition andmorphological features of these radiolarians a new genus Eoconcharium and a new family Eocon-chariidae are erected.     

SYNTHESIS AND BIOLOGICAL ACTIVITY OF A NEW FROG SKIN PEPTIDE, RANAMARGARIN

A new frog skin peptide, ranamargarin depicted as H-Asp-Asp-Ala-Ser-Asp-Arg-Ala-Lys-Lys-Phe-Tyr-Gly-Leu-Met-NH_(2′), was synthesized by the conventionalmethod. Comparisons of chemical and biological properties of both the synthetic and natural ranamargarins indicated that they were identical, so the chemical structure of ranamargarin was confirmed. Preliminary pharmacological study showed that ranamargarin was highly selective towards the SP-P subtype receptor.     

STUDIES ON ORGANOMETALLIC COMPOUNDS OF TITANIUM,ZIRCONIUM AND HAFNIUM TITANIUM, ZIRCONIUM AND HAFNIUM——SYNTHESES AND PROPERTIES OF BIS (CYCLOPENTADIENYL) DI-(ARYLOXY) DERIVATIVES

The dichlorides of bis(cyclopentadienyl) or bis(methylcyclopentadienyl) titanium, zircon-ium and hafnium reacting with phenol or substituted phenols in the presence of base give aseries of new aryloxymetal derivatives. The activities of chlorine atoms in the dichlorides ofbis(cyclopentadienyl)titanium, zirconium and hafnium molecules towards phenols are compared.The influence upon HNMR of the cyclopentadienyl ring due to the electronegativities of themetals and the substituents on the phenyl rings, as well as the number and position of thesubstituents are discussed.     

THE CHEMICAL COMPOSITIONS OF MINERALS IN QINGZHEN METEORITE AND ITS GEOCHEMISTRY SIGNIFICANCE

The chemical compositions of silicate minerals, sulphide minerals and metal Fe-Ni in theQingzhen meteorite were measured by the microprobe analyses. Based upon these chemicalcompositions, the cosmochemical behaviour and characteristics of the existing forms of themajor elements in the Qinzhen meteorite have been discussed. These characteristics show thatunder the S-rich, O-poor, and strongly reducing conditions, the light metal elements, such asCa, Mg, K, Na may form sulphide, and metal Fe-Ni may contain Si and P. However, we con-sider that the light metal-sulphide can be stable in the lower mantle and there are some Siand P in the Fe-Ni core. Finally, an earth core-mantle model is established, where the Fe-Ni core contains some Si and P; the lower mantle is composed of Mg-rich silicate, SiO_2 andsulphide; the upper mantle, of silicate and oxide.     

GEOCHEMISTRY OF TRACE ELEMENTS IN DEEP-SEA SEDIMENTS OF THE SOUTH CHINA SEA

Mathematical-geological studies of trace elements in deep-sea sediments of the South China Sea have been made on the basis of the information developed from Q-factor analysis. The factors controlling the trace element distribution appear to be (ⅰ) sedimentary facies related to water depth and submarine volcanism, and (ⅱ) authigenous precipitation associated with chemical or biochemical process. The characteristics of migration and concentration of trace elements are described as follows: (ⅰ) The elements Ni, Cu and Co are probably related to the adsorption of autMgenous colloidal Mn-solids; (ⅱ) some elements, such as B, Cr, Zr and Ti are largely adsorbed on clay minerals; (ⅲ) both Sr and Ca are of biogeneous enrichment; (ⅳ) Ba intergrows with Cu, Pb and Ag, indicating that Ba results mainly from submarine volcanic activity and partly from biological process.     

THE ROLE OF INSULIN MEDIATORS IN REGULATION OF cAMP AND LIPOGENESIS AS WELL AS IN DIABETES

Plasma membranes prepared from pig, mouse and rat liver incubated with insulin resulted in the release of at least two insulin chemical mediators. These mediators, identified as fractions 1 and 3, were found to inhibit cAMP level in response to lipolytic hormone and forskolin and to enhance lipogenesis in adipocytes of rat. Fractions 1 and 3 have been estimated to have molecular weights of 3700—4000 and 1000—1500 dalton, respectively. This initial report will focus on fraction 1.Interestingly, liver membranes from diabetic animals were found not to release mediators in the presence of insulin. However, following in vivo treatment of diabetic animals with insulin, the liver membranes appeared to restore its ability in generating chemical mediators in response to insulin.     

THE REDOX BEHAVIOR OF BISMUTH MOLYBDATES——AN XPS STUDY OF Ar~+ ION BOMBARDMENT INDUCED CHEMICAL EFFECT IN UHV

Ar~+ ion bombardment induced reduction effect on Bi_2O_3, MoO_3 and Bi-Mo complex oxides, α-Bi_2Mo_3O_(13), β-Bi_2Mo_2O_9, and γ-Bi_2MoO_6, has been studied with XPS. The results show that, owing to the presence of the oxygen anion bridge in Bi(Ⅲ)-O(Ⅱ)-Mo(Ⅵ), the reduction behavior of Bi(Ⅲ) and Mo(Ⅵ) metal ions in all the three complex oxides is contrary to that in the single oxides. While Mo(Ⅵ) in MoO_3 is reduced to Mo(Ⅵ) in UHV under Ar~+ ion bombardment, the valence state of Bi(Ⅲ) in Bi_2O_3 is unchanged. However, Bi(Ⅲ) in the three complex oxides is reduced to Bi(0) without noticeable reduction of Mo(Ⅵ). Nevertheless, the rates of Bi(Ⅲ) reduction are in correspondence with the difference in Bi/Mo atomic ratio and the crystallographic features of the three phases of bismuth molybdate are decreasing in the order of α-Bi_2Mo_3O_(12)≥β-Bi_2Mo_2O_9>γ-Bi_2MoO_6. A new O -species is observed on the bismuth molybdate surface reduced by Ar~+ ion bombardment.Wc discuss the above phenomena i     

THE CRYSTAL STRUCTURE OF YIMENGITE

Yimengite is a new species of mineral discovered in Shandong Province in 1980, with crystal chemical formula K(Cr, Ti, Fe, Mg, Al, Si)_(12)O_(19). It belongs to hexagonal system, and its cell parameters α_0=5.857 and c_0=22.940. 749 separate diffraction intensities of crystal were collected on RASA=IIS auto-four-circle single crystal diffractometer.All atomic coordination, temperature factor and degree of occupation were obtained by RASA-SAP interpretation system, and XTL crystallographic procedure, atomic distances and bond angles for each atom were calculated. Deviation factor R is 0.080.Through the medium of determination of the crystal structure of the new mineral yimengite, coordination form of monovaleace alkali metal element—potassium, etc. in high pressure have been cleared, a five fold coordination form of Fe cations—regular bipyramid has been established, and some new information on the geochemical state of some elements, such as Cr, Ti, etc. have been provided.     

PRELIMINARY RESEARCH ON CLAY MINERALS IN SALT LAKE SEDIMENTS OF CHINA AND ITS SIGNIFICANCE

Most of the clay minerals in salt lakes of China are characterized by illite-chlorite as-semblage, with a minor amount of montmorillonite and kaolinite and so on. There are ob-vious differences between mineral assemblages, relative contents and chemical compositionof clay minerals in salt lakes of different areas and in different sedimentary stages. Clayminerals in these salt lakes are basically allogenic, but transitional origin may also exist.The characteristics of clay minerals in salt lakes are controlled by the arid climatic zone ofChina and the different material supplies of salt lakes. With the data taken from clay miner-al study, the author discusses the relation of sedimentary environment of salt lakes, theregularities of immigration and enrichment of mineralization elements.     

PREPARATION AND CHARACTERIZATION OF ION EXCHANGE MEMBRANES BASED ON POLYVINYLIDENE FLUORIDE

A new ion exchange membrane based on polyvinylidene fluoride (PVDF) and sulfonated poly(styrenedivinylbenzene) was prepared by in-situ polymerization. The incorporation of sulfonic groups into the polyvinylidene fluoride composite membrane was confirmed by infrared spectroscopy (IR), ion exchange capacity (IEC) and energy dispersive X-ray analysis (EDAX). Area resistance, IEC and water uptake of the treated membrane were evaluated. When area resistance in NaCl aqueous solution at 25℃, IEC is as high as 2.43 millimoles per gram of the wet membrane. The hydrophilicity of PVDF membrane is also significantly improved after treatment. When 60% of crosslinked membrane was sulfonated at 80℃ for 6 h, water uptake of the treated membrane can attain 64.7%.     

REDOX VARIATIONS OF THE ANCIENT OCEAN IN THE WESTERN MARGIN OF THE TARIM BASIN——THE EVIDENCE FROM Ce ANOMALIES OF MARINE SHELL FOSSILS

Two episodes of paleoredox fluctuation variation are indicated in some localities in thelate Cretaceous--early Tertiary ocean of western Tarim recorded by REE distribution patterns,Ce anomalies, and Th/U ratios from systematic studies on the chemical composition, withspecial reference to REE and 20 trace elements, based on 11 marine shell fossils occurringin the Upper Cretaceous--Lower Tertiary strata of the western Tarim Basin, Xinjiang. Thefactors Controlling the redox fluctuation may be probably caused by shifting places ofsurface runoff put into the sea as a result of transgression and regression.     

CHARACTERISTICS, DIAGNOSTIC CRITERIA AND GEOLOGICAL SIGNIFICANCE OF PYROCLASTIC SURGE DEPOSITS

Study has been performed on the characteristics of the pyroclastic surge deposits in the northern Yandangshan area of Zhejiang Province. Based on this study and the relative research of other scholars, five major diagnostic criteria of the deposits have been proposed. Moreover, the geological significance of the study on the deposits has been discussed.     

FOURIER TRANSFORM FAR INFRARED SPECTRA AND NORMAL COORDINATE ANALYSIS OF FIFTEEN RARE-EARTH OXALATE HYDRATES

The Fourier transform far infrared spectra of oxalate hydrates of whole rare-earth series except Pm and Sc are investigated in the range of 100-400 cm~(-1). The assignment of vibrational frequencies is made on the basis of normal coordinate analysis using our NORVIB program. The model used for the hghter elements of the lanthanide series (La to Eu) is based on the crystal structure of Nd_2(C_2O_4)_3. 10H_2O, in which each lanthanide ion is surrounded by nine O atoms, six from three oxalate ions and three from Water molecules.The model adopted for the heavier elements of the lanthanide series (Gd to Lu) and Ytterbium is based on the crystal structure of Yb_2(C_2O_4)_3· 6H_2O, in which each ion is surrounded by eight atoms, six from three oxalate ions and two from water molecules. The variation of the metal-ligand frequencies and force constants with the atomic numbers of lanthanides is plotted and discussed.     

CHEMICAL MODIFICATION OF SULFHYDRYL GROUPS OF E.coli LEUCYL-tRNA SYNTHE-TASE AND SEQUENCING OF [~(14)C]NEM-LABELED PEPTIDES

The chemical modification of the sulfhydryl groups of E. coli Leucyl--tRNA synthetase(LeuRS) by DTNB, NEM and IAA resulted in a time-dependent loss of both amino-acid acti-vation and aminoacylation activities in parallel. The second-order reaction constants of DTNB,NEM and IAA were 1700, 150 and 0.46 mol/L~(-1) min~(-1) respectively. Chemical stoichiometryshowed that only one sulfhydryl group of LeuRS was essential for both activities. Substratesleucine and Leu-AMP protected the active sulfhydryl group from modification, suggestingthat the modified sulfhydryl group is located in or near the active site region responsiblefor amino-acid activation. [~(14)C]NEM--labeled LeuRS was subjected to tryptic digestion, andpeptides were separated and sequenced. 179 Cys~*-Asp-Thr-Leu182 was identified as the major[~(14)C]NEM-labeled site in LeuRS. This result is consistent with the previous observationthat the region for Leu--AMP formation was located at the N--terminal part of LeuRS.