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Eastern Shandong is one of the most economically important regions for ore‐producing sedimentary‐metamorphic graphite deposits in China. The Liugezhuang and Daliangzikou graphite deposits in the Pingdu–Laixi Graphite Belt are typical examples. The ores in the Liugezhuang deposit and Daliangzikou deposit are typically gneiss/granulite type and biotite granulite type, respectively. Graphite occurs as stratabound layers of slender flakes associated with biotite, clinopyroxene, and plagioclase and as slender flakes and disseminated grains associated with biotite and filling tiny fractures in mineral grains. The mineral associations indicate that the ore rocks can be classified into four metamorphic facies: (a) amphibolite granulite facies, Cpx (Hy) + Opx (Di) + Pl ± Hbl ± Qz; (b) amphibolite facies, Hbl + Pl + Cpx (Opm) + Ep + Bt + Ms + Qz ± Chl ± Mic; (c) high‐grade greenshist facies, Hbl + Pl + Ep + Bt + Chl + Qz ± Cpx; and (d) low‐grade greenshist facies, Ep + Chl + Pl + Bt + Ms + Chl + Qz + Rt. Study of the variation in graphite crystals and fixed carbon with increasing metamorphic grade suggests that more than one metamorphism process (graphitization) occurred during ore formation. Geochemical analysis indicates that the primary condition under which the Liugezhuang and Daliangzikou graphite deposits formed was a marine facies sedimentary environment of which the material source was terrestrial weathering detritus and compounds and also a participation of terrestrial material in the graphite deposits. Trace element data suggest that the sedimentary condition was from a reducing condition in the Liugezhuang graphite deposit to a weaker reducing condition in the Daliangzikou graphite deposit, whereas samples from a Jingshan Group stratum show multiple oxidation–reduction conditions but dominantly oxidation. Carbon isotope analysis indicates that the carbon source of the Liugezhuang graphite deposit was organic, whereas that of the Daliangzikou graphite deposit was mainly organic carbon but with some inorganic participation. [ABSTRACT FROM AUTHOR]

Orebodies in the Xiadian gold deposit in the Jiaodong Peninsula, China are mainly hosted in the Mesozoic granitoids, controlled structurally by the Zhaoyuan–Pingdu Fault Zone, and occur as disseminated and cataclastic altered type. Four mineralization stages were identified as follows: quartz–pyrite stage (I), gold‐bearing fine‐grained pyrite–quartz stage (II), polymetallic sulfide–quartz stage (III), and quartz–carbonate stage (IV). Quartz was classified as including quartz granules with dentation boundaries (I), cataclastic quartz grain assemblages (II and III), and rod‐like quartz grains (IV). Petrography, laser Raman analysis, and microthermometry of fluid inclusions in these stages (in both tunnel and borehole samples) reveal (a) CO2–H2O fluid inclusions (C–H type), (b) CO2–H2O ± CH4 fluid inclusions (C–H–CH4 type), and (c) aqueous fluid inclusions (H type). Fluid immiscibility caused by fluid mixing caused rapid precipitation of gold. The ore‐forming fluid of the Xiadian gold deposit evolves from an H2O–CO2–NaCl ± CH4 system with medium temperature and salinity to an H2O–NaCl system with low temperature and salinity, from CO2‐rich to CO2‐poor in composition and from a mixture of magmatic water with increasing meteoric water as δ18OH2O values. Sulphur isotope compositions suggest a mixed source of ore metal, and the Jiaodong Group may be a major source for sulphur. Fluid parameters of borehole samples indicate that there is the same fluid system for Au precipitation at different depths and fault gouge with poor permeability may play a crucial role in forming a relatively closed semi‐open space for Au precipitation. Integrating the data obtained from the studies including regional geology, ore geology, and fluid inclusions and stable isotope geochemistry, the Xiadian gold deposit is concluded as an orogenic‐type gold deposit formed in the tectonic transition from compression to extension. [ABSTRACT FROM AUTHOR]

The seed of the plant Jatropha curcas contains a toxic protein, designated as curcin, which was purified to apparent homogeneity by the combined use of chromatography on Sephdex G-100. The molecular weight of 28.2 kDa and the pI of 8.54 were determined. The protein was found to be a glycoprotein; the total neutral-surge content was 4.91%. It strongly inhibits the protein synthesis of rabbit reticulocyte lysate, with an IC50 of 0.42 nM. It was determined by Edman that the sequence of the N-terminal thirty-two amino acids was: A-G/Y-S/K-T/A-P/D-T-L-T-I-T-Y-D-A-T/A-A-D-K-K-N-Y-A-Q-F-I-K-D-L-R-E-A-F/A-G. The isolated curcin had a hemagglutinating activity, when its concentration was more than 7.8 mg/L. The secondary structure of curcin was analyzed by Circular Dichroism (CD) spectrum. The result shows the curcin contains α-helix (22.3%), β-sheet (43.5%), and random coil and corner (34.2%). The results of acute toxicity in mice show that mice oral semi-lethal dose LD50 was 104.737 ± 29.447 mg/kg; mice parenteral semi-lethal dose LD50 was 67.20 ± 10.445 mg/kg. [ABSTRACT FROM AUTHOR]