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A comparative study of the aromaticity in some typical conjugated six-membered rings by the method of localized molecular orbital

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Chinese Journal of Chemistry 1991年第5期9卷 385-392页

作者： CHEN Zhi-Da lu jia-xi LI Jun LIU Chun-Wan ZHANG Qian-Er Fujian Institute of Research on the Structure of Matter Fuzhou Research Laboratory of Structural ChemistryAcademia SinicaFuzhou 350002

The localized molecular orbitals and energy levels for four typical conjugated six-membered ring systems C_6H_6, C_3N_3H_3, B_3N_3H_6, and (B_3O_6)^(3-) as well as a non-aromatic reference molecule N_3Cl_6 have been calculated by using Edmiston-Ruedenberg energy localization technique under the CNDO/2 approximation in order to investigate the nature of aromaticity or quasi-aromaticity of the six-membered ring systems studied. The contour maps for π-type localized MO's (LMO) have been plotted to illustrate the bonding characteristics of the five ring systems studied. These LMO calculations show that for all the conjugated six-membered ring systems considered there exists local delocalization of π-bonds or three-centered and occasionally four-centered two-electron π-bonds in our terminology, and the cooperative effect among these π-bonds leading to the formation of a closed continuous x-conjugation system around the ring, which is necessary for the creation of aromaticity in the systems studied. We have been able to discuss the properties of these three-centered π-bonds in terms of the constituent atoms and electrons and the relevant orbitals involved.

关键词： A comparative study of the aromaticity in some typical conjugated six-membered rings by the method of localized molecular orbital

The crystal and molecular structure of hexachloro-tris（μ-allylthiourea）ditungsten （III） monohydrate{W2[SC（NH2）NHCH2CHCH2]3Cl6}·H2O

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Chinese Journal of Chemistry 1984年第1期2卷 6-12页

作者： lu Shao-Fang SHANG Mao-Yu HUANG Jin-Ling lu jia-xi Fujian Institute of Structure of Matter,Academia Sinica,Fuzhou,Fujian Fujian Institute of Structure of Matter Academia Sinica Fuzhou Fujian

A new kind of binuclear tungsten complex{W2[SC（NH2）NHCH2CHCH2J3Cl6}·H2Owas synthesized by mixing a concentrated hydrochloric acid solution of[W2Cl9]3-with allylthiourea andinvestigated by X-ray structural *** crystal is monoclinic,belonging to the space groupP21,with the following parameters:a=8.496（1）A,b=18.760（2）A,c=8.591（1）A,β=91.36（1）°and Z=2 with Do=2.297 ***（-3）.The structure was solved by heavy atom method and differenceFourier synthesis and refined by full-matrix least-squares technique to a final R factor of 0.038 for2812 independent reflections with I≥3σ（I）.The result shows that in the structure each W atom forms an octahedral coordination with threeCl atoms and three bridging S atoms of the allylthiourea *** two octahedra share a com-mon face to form a binuclear complex with a very much shorter W-W bond distance(2.443（1）A),indicating a strong interaction between the two W *** from the orientation of the thiourealigand groups with respect to the W-S bonds,the thiourea S atoms are coordinated to the two W atomsin different *** is noted that one of the two W atoms is located at the point of intersection ofthe three thiourea planes,while the other W atom is located quite apart from these thiourea planeswith three W-S bonds nearly perpendicular to each of them respectively.

关键词： allylthiourea)ditungsten monohydrate{W2[SC NH2)NHCH2CHCH2 III Cl

Estimation of Iron Physiological Requirement in Chinese Children using Single Stable Isotope Tracer Technique

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Biomedical and Environmental Sciences 2022年第8期35卷 681-687页

作者： ZHANG Yu LIU xiao Bing REN Tong xiang CAI Jie lu jia xi NIU Ran PIAO jian Hua YANG Li Chen WANG Jun YANG xiao Guang Chinese Center for Disease Control and Prevention Beijing 102206China Gansu Center for Disease Control and Prevention Gansu 73000LanzhouChina Key Laboratory of Trace Element Nutrition MOHNational Institute for Nutrition and HealthChinese Center for Disease Control and PreventionBeijing 100050China National Institute of Metrology Bejing 100029China Department of General Surgery Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBejing 100730China

Objective This study is to obtain precise data on iron physiological requirements in Chinese children using single stable isotope *** Thirty boys(10.6±0.2 years)and 27 girls(10.4±0.2 years)were received oral 6 mg ^(57)Fe each day for 5 consecutive *** blood samples were subsequently drawn to examine the change of total iron concentration and ^(57)Fe abundance at day 0,14,28,60,90,180,360,450,540,630,*** iron physiological requirement was calculated by iron loss combined with iron circulation rate once ^(57)Fe abundance stabilized in human *** The iron physiological requirement was significantly lower in boys than those values in girls(16.88±7.12 vs.18.40±8.81μg/kg per day,Plues were calculated as 722.46±8.43μg/day for boys and 708.40±7.55μg/day for girls,*** nearly 10%iron absorption rate,the estimated average iron physiological requirement was 6.0 mg/day in boys and 6.2 mg/day in *** This study indicate that iron physiological requirement could require more daily iron intake in girls as compare with the values in boys having the same body *** findings would be facilitate to the new revised dietary reference intakes.

关键词： Iron absorption rate Physiological requirement Chinese children Stale isotope tracer Dietary reference intakes

Research on in part "loosely" coordinated trinuclear molybdenum cluster compounds—— the synthesis and crystal structure of {Mo3（μ3-S）(μ-S)3[S2P（OEt）2]4·P（C6H5）3} （0.86CH2Cl2）

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Chinese Journal of Chemistry 1986年第4期4卷 301-310页

作者： HUANG jian-Quan lu Shao-Fang LIN Yu-Hui HUANG Jin-Ling lu jia-xi Fujian Institute of Research on the Structure of Matter, Academia Sinica, Fuzhou Fujian Institute of Research on the Structure of Matter Academia Sinica Fuzhou

The synthesis and crystal structure of novel trinuclear molybdenum cluster compoundwith somewha "loose" coordination site {Mo3（μ3-S）(μ-S)3[S2P（OEt）2]4· P（C6H5）3}'·（0.86 CH2Cl2）have been reported. The cluster crystallizes in the spece group Pl with two molecules in a unit cellwhose parameters are a=10.472（4）, b=14.375（2）, c=21.695（3）; a=74.O4（1）°, β=76.50（2）°, γ=72.22（2）°, v=2950 and D_o=1.693 ***-x. On the basis of 4840 independent reflections with I≥2σ（1）.the structure was solved by heavy atom method and Fourier method and refined by full-matrixleast-squares techniques to a final R=0.058. The distances between Mo atoms in this cluster are 2.731（1）, 2.748（1） and 2.753（1） *** mean value of Mo--Mo bond lengths is slighly shorter than those in other trinuclear Mo clusterswith "looscly coordinated" site. In addition, the PPh3ligand is loosely coordinated to one Mo atomin direction opposite to the μ3-S with Mo--P bond length of 2.647（3）. This is different from theother strocturally analogous clusters, in which the loosely coordinated ligand is trans to μ2--S. Asummary of Mo--Mo and Mo-L bonding for such clusters is given.

关键词： Mo3 the synthesis and crystal structure of OEt Research on in part S2P coordinated trinuclear molybdenum cluster compounds loosely CH Cl

FT-IR spectra and normal coordinate analysis of the [Cl2FeS2MoS2FeCl2]2-dianion

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Chinese Journal of Chemistry 1988年第1期6卷 1-6页

作者： LIN Zheng-Yan HE Ling-Jie ZHANG Lin-Na lu jia-xi Fujian Institute of Research on the Structure of Matter,Academia Sinica,Fuzhou Fujian Institute of Research on the Structure of Matter Academia Sinica Fuzhou

The FT-IR spectra of the[ClFeSMoSFeCl]dianion were measured in the range500 to 100 cm.A simplified general valence force field was used in a normal coordinate *** calculated frequencies agree well with the observed values,with a mean deviation of less than1.0%,thus confirming the assignments of the vibrational *** 16 force constants,including stretching,bending,torsion and stretching-stretching interactions were *** and the reliability of the results were discussed.

关键词： Cl2FeS2MoS2FeCl2 In dianion FeS FT-IR spectra and normal coordinate analysis of the IR

Syntheses and structural studies of molybdenum-iron-sulfur compounds Ⅰ. The synthesis and crystal structure of （Et4N）[Mo2Fe7S8（SPh）12]

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Chinese Journal of Chemistry 1986年第3期4卷 209-216页

作者： KANG Bei-Sheng CAI Jing-Hua CHENG Chang-Neng lu jia-xi Fujian Institute of Research on the Structure of Matter, Academia Sinica, Fuzhou Fujian Institute of Research on the Structure of Matter Academia Sinica Fuzhou

Through the reactions of ferrous thiolates with tetrathiomolybdate, we discussed thereaction pathways and possible intermediates during the formation of double-cubane type Mo-Fe-Scluster compounds. We also reported the synthesis, crystal structure, IR and magnetic susceptibi-lity measurements of the title compound 2. The crystal of 2 belongs to triclinic system, Mr=2670.3;P1; a=12.755（4）A, b=13.076（3）A, c=20.576（4） A; α=80.00 （2）°, β=81.39（2）°, γ=61.51（2）°;V=2966.3（14）A3; Z=1; Dc=1.495 g/cm2. Final R factor is 0.077 for 4031 observed *** compound was obtained through the reaction of （Et4N）2[Fe4（SPh）10] （1） with （Et4N）2MoS4inacetonitrile solution. The structure of anion 2 is two cubane clusters bridged by a Fe（SPh）*** Mo…Mo′ distance of 7.188A is the longest among all double-cubane cluster compounds ofknown structures.

关键词： Fe Syntheses and structural studies of molybdenum-iron-sulfur compounds SPh Et4N The synthesis and crystal structure of Mo2Fe7S8

Serum vaspin level in relation to postprandial plasma glucose concentration in subjects with diabetes

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Chinese Medical Journal 2009年第21期122卷 2530-2533页

作者： YE Yin HOU Xu-hong PAN xiao-ping lu Jun-xi jia Wei-ping Department of Endocrinology and Metabolism Shanghai Clinical Center for Diabetes Shanghai jiao Tong University Affiliated Sixth People's Hospital Shanghai Diabetes Institute Shanghai Key Laboratory of Diabetes Mellitus Shanghai 200233 China

Background Vaspin is a newly-identified adipocytokine related to obesity and insulin sensitivity. However, its pathophysiologic role in humans remains largely unknown. The aim of our study was to investigate the relationship between serum vaspin level and glucose metabolism or obesity in Chinese adults. Methods A total of 123 subjects, including 84 subjects with normal glucose tolerance （NGT） and 39 subjects with diabetes, were enrolled in this study. Anthropometric parameters, abdominal fat areas, plasma glucose concentration, serum insulin, lipids, and vaspin level were measured in each participant. Results Serum vaspin concentration was significantly higher in diabetic patients than that in NGT subjects （592 （438-695） pg/ml vs 380 （294-517） pg/ml, P=0.020） in women. In all participants, age, fasting plasma glucose concentration （FPG）, 2-hour post-load plasma glucose （PG2h）, hemoglobin Alc （HbAlc） and high-density lipoprotein cholesterol （HDL-c） significantly increased from the lower tertile to the higher tertile of vaspin. Univariate linear regression analyses revealed that vaspin level was only positively correlated with age （β=0.340, P=0.002） in NGT subjects. And vaspin was positively associated with FPG （β=0.365, P=0.023）, PG2h （β=0.526, P=0.001）, HbAlc （β=0.388, P=0.016）, and HDL-c （β=0.353, P=0.027）, while negatively with homeostasis model assessment of beta cell function （HOMA-β）（β=-0.361, P=-0.024） in diabetic patients. In stepwise multivariate regression analyses, age was independently associated with circulating vaspin in NGT subjects, whereas PG2h was an independent predictor of vaspin in diabetic patients. In addition, there was no significant difference of serum vaspin level between men and women. And no significant correlations between vaspin and body fat indexes were detected. Conclusions Serum vaspin level is higher in diabetic patients than that in NGT subjects in women. Age predicts serum vaspin level in NGT subjects, while PG2h is independently

关键词： vaspin protein, human blood glucose diabetes mellitus obesity

CRYSTAL STRUCTURE OF [Mo3S4 （μ-CH3COO） [S2P（OEt）2]3 （py）] （CH3COOCH2CH3）

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Chinese Journal of Structural Chemistry 1990年第2期 116-120页

作者： lu Shao-Fang Huang jian-Quan Huang Zi-xiang Huang Jin-Ling lu jia-xi Fujian Institute of Research on the structure of Matter, Academia Sinica

[Mo3S4(μ-CH3COO)[S2P(OEt)2]3(py)]·(CH3COOCH2CH3) , Mr = 1197. 96,monoclinic,P21/n,a=13. 158(2),b=23. 153(5), c=16. 175(3) A,β = 112. 79(1)°,V=4543. 1(7)A3,Z=4, Dc= 1. 751g/cm-3,λ(MoKa) = 0. 71073A ,μ= 13. 799cm-1,F(000) = 2408. Final R=0. 067 for 4000 reflections. The structure consists of the neutral cluster molecule [Mo3S4(μ-OAc) (dtp)3(py)] (dtp = [S2P(OEt)2]) and the solvent ethyl acetate (AcOEt). The three Mo-Mo bond lengths in the title compound are 2. 691(2) ,2. 747(2) ,2. 762(2) A ,whereas the Mo-N bond length in Mo(3) position is 2. 36(2)A. The important bond lengths of these Mo clusters with (py) ring at the loose coordination site are listed for comparison.

关键词： Mo3S4 S2P CRYSTAL STRUCTURE OF OEt CH3COOCH2CH3

Structure of the Heterobimetallic Linear-Chain Polymeric Complex [NH_4]_n [WAgS_4]_n and Influence of Cationic Valence State on Configurations of Polymeric W/Ag/S Complexes

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Chinese Journal of Structural Chemistry 1997年第4期16卷 253-257页

作者： HUANG Qun WU xin-Tao lu jia-xi(State Key Laboratory of Structural Chemistry, Fujian Institute of Research onthe Structure of Matter, the Chinese Academy of Sciences, Fuzhou 350002) 中科院福建物质结构所结构化学国家重点实验室福建福州

The title complex [NH4]n [WAgS4]n crystallizes in the tetragonalspace group I4 with crystallographic parameters: a = b = 7. 994 (2 ), c = 5. 855 (2 ):A,V = 373. g(2) A3, Z=2, Dc= 3. 89 g/cm3, F(000) = 392, μ= 19. 27 mm-l , A(MoKα) = 0. 71069, Mr = 438. 01, and the convergence factors R = 0. 045, Rw =0. 055 for 341 observed reflections (I>3σ(I)). The anion structure can be viewed as apolymeric single chain consisting of unlimited extended rhombic fragruents of -AgS2W-which are alternately perpendicular to each other. Additionally, influence of di- and tri-valent complex cations on the assembIy of WS2-4 and Ag+ is briefly discussed.

关键词： tungsten complex silver complex polymeric linear-chain complex crystal structure