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New thiopyran-4-spiro-2′-(1,3-dithiolane):Formation mechanism and crystal structure

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Chinese Chemical Letters 2011年第3期22卷 280-283页

作者： Hong Qi li zhong Bao zhang lin li Key Laboratory of Science & Technology of Eco-Textile Ministry of Education College of Chemistry Chemical Engineering and Biotechnology Donghua University Shanghai 201620 China

Ethylene trithiocarbonate reacted with dimethyl acetylenedicarboxylate to furnish tetramethyl thiopyran-4-spiro-2＇-（1,3- dithiolane）-2,3,5,6-tetracarboxylate,a new thiopyran-4-spiro-2＇-（1,3-dithiolane） heterocyclic compound,as the minor product together with the major product dimethyl 2-thioxo-1,3-dithiole-4,*** new heterocycle was probably formed through a[2 ＋ 2]cycloaddition between ethylene trithiocarbonate and dimethyl acetylenedicarboxylate followed by a 1,3-dipolar cycloaddition or[4 ＋ 2]*** structure of the new compound revealed that the thiopyran ring and 1,3-dithiolane moiety were perpendicular to each other.

关键词： Thiopyran-4-spiro-2'-(1 3-dithiolane) Cycloaddition Mechanism Crystal structure

Inhibitory effects of N-(4-hydrophenyl) retinamide on liver cancer and malignant melanoma cells

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World Journal of Gastroenterology 2005年第37期11卷 5763-5769页

作者： Xing-zhong Wu li zhang Bi-Zhi Shi Ping Hu Department of Biochemistry and Molecular Biology Shanghai Medical College Fudan University Shanghai 200032 China

AIM: To investigate the effect of N-(4-hydrophenyl) retinamide (4-HPR), the derivative of retinoic acid, on inhibition of migration, invasion, cell growth, and induction of apoptosis in hepatocellular carcinoma cells (HCCs) and malignant melanoma ***: 4-HPR was chemically synthesized. Cellular migration and invasion were assayed by Borden chamber experiment. Cell growth was assayed by MTT *** effect was measured using Hoechst 32258 staining and flow cytometry. Gene transfection was performed with ***: We observed that the migration of HCC and melanoma cells was significantly suppressed by 4-HPR and the migration cells were reduced to 58±5.03 (control 201±27.2, P＜0.05, n = 4) in SMMC 7721-k3 HCC, and to 254±25.04 (control 302±30.1, P＜0.05, n = 4) in melanoma cells after 6-h incubation with 4-HPR. The invasion through reconstituted basement membrane was also significantly reduced by 4-HPR treatment to 11.2±3.3 in SMMC 7721-k3 HCC (control 27±13.1), and to 24.3±3.2 in melanoma cells (control 67.5±10.1, P＜0.05, n = 3). Cell growth, especially in melanoma cells, was also significantly ***, 3 μmol/L of 4-HPR induced apoptosis in B16 melanoma cells (37.11±0.94%) more significantly than all-trans retinoic acid (P＜0.05), but it failed to induce apoptosis in SMMC 7721-k3 HCC. The mechanism for 4-HPR-induced apoptosis was not clear, but we observed that 4-HPR could regulate p27kip1, and overexpression of cerebroside sulfotransferase (CST) diminished the apoptosis induced by 4-HPR in melanoma ***: 4-HPR is a potent inhibitor of HCC migration and inducer of melanoma cell apoptosis. CST and p27kip1 expression might be associated with 4-HPR-induced apoptosis.

关键词： N-(4-hydrophenyl) retinamide Apoptosis CST p27^kip1

Clumpy metal concentrations in elliptical galaxies NGC 4374 and NGC 4636

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Research in Astronomy and Astrophysics 2010年第3期10卷 220-226页

作者： Hai-Guang Xu Jun-Hua Gu li-Yi Gu zhong-li zhang Yu Wang Tao An Department of Physics Shanghai Jiao Tong University Shanghai 200240 China Max-Planck Institut fur Astrophysik D-85740 Garching Germany Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China

We present a high spatial resolution study of metal distributions in the nearby, gas-rich elliptical galaxies NGC 4374 and NGC 4636 with the Chandra ACIS archive data. We define the hardness ratio HRFeL as the ratio of the emission in 0.65- 1.4 keV to that in 0.3-0.6 keV and 1.4-3.5 keV （after the magnesium and silicon lines are excluded）, and HRcont as the ratio of the emission in 1.4-3.5keV to that in 0.3- 0.6 keV, so that the HRFeL and HRcont maps can be used to trace the iron abundance and gas temperature distributions, respectively. By applying the a Trous wavelet algorithm to the obtained emission hardness ratio maps, we reveal that the HRFeL distributions are highly irregular, exhibiting strong spatial variations on 0.1-1 Re scales, which do not follow the HRcont distributions. Since the effect of temperature variation is small, we conclude that most of the high-HRFeL regions are very likely to possess higher abundances than the ambient gas. We also find that these high-HRFeL substructures are not associated with either the LMXB or globular cluster populations, thus their origins should be related to AGN activity or mergers.

关键词： galaxies: elliptical and lenticular cD -- galaxies: individual (NGC 4374 NGC 4636) -- galaxies: ISM -- ISM: abundances -- X-rays: galaxies

Controlled Radical Polymerization of Methyl Methacrylate Catalyzed by Hybrid Supported Iron Catalyst

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Chemical Research in Chinese Universities 2005年第6期21卷 737-739页

作者： li zhong-hui, zhang Yong-ming XUE Min-zhao ZHOU Lei liU Yan-gang College of Chemistry and Chemical Engineering Shanghai Jiaotong University Shanghai 200240 P. R. China

A supported iron catalyst, which was prepared by anchoring FeCl2/FeCl3 on the cross-linking macroporous polyacrylate ion exchange resin, was evaluated via the controlled radical polymerization. When a small amount of CuCl2/ Me6TREN was added, the controllability of the polymerization over the iron-mediated catalyst was significantly improved（Mw/Mn = 1.23-1.73 ）, affording a polymer with a low residual metal via a simple catalyst separation procedure. After suitable regeneration, the supported iron catalyst could also he recycled. UV-Vis analysis showed that the additional copper catalyst could facilitate the radical deactivation process.

关键词： Controlled radical polymerization Supported catalyst Iron halide Copper halide

Changes in Organic Carbon and Nutrient Contents of Highly Productive Paddy Soils in Yujiang County of Jiangxi Province,China and Their Environmental Application

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Agricultural Sciences in China 2006年第7期5卷 522-529页

作者： li zhong-pei zhang Tao-lin CHEN Bi-yun Institute of Soil Science the Chinese Academy of Sciences Nanjing 210008 P.R. China

Paddy field is an important land use in subtropical China. Development of high soil fertility and productivity is the management goal of paddy field, Fertilization and management practices have not only influenced the status of organic matter and nutrients in the soil but also affected the environmental quality. This article investigates the contents of organic carbon and the nutrients, and the change over the last 20 years in highly productive paddy soils and their environmental application. Field soils were sampled and the analytical results were compared with the corresponding values in the Second Soil Survey in Yujiang County of Jiangxi Province, China. The results showed that surface soils at a depth of 0-10 cm in highly productive paddy fields in Yujiang County of Jiangxi Province had contents of organic carbon （20.2 ±3.88） g kg^-1, total nitrogen （2.09±0.55） g kg^-1, and available phosphorus （42.7 ±32.7） mg kg^-1, respectively, which were all at very rich levels. Over the last 20 years, the organic carbon pool of the highly productive paddy soils reached a steady state. Total N and available P significantly increased, whereas available K changed a little. The amount and percentage of P immobilization in the surface soil （0-10 cm） of highly productive paddy fields were （142.7 ~ 41.1） mg kg-~ and （36.2~ 10.4）% of added P, and CEC （7.93 ~ 1.32） cmol kg-~. These two parameters were not higher than the mean values of paddy soils and upland red soils in the areas. Results also showed that fertilizer P in highly productive paddy soils had a high mobility and was prone to move toward a water body, which is the main source of nutrients causing eutrophication. Because of a weak K-fixing capacity, the available K content was not high in highly productive paddy soils. This suggests that attention should be paid to the K balance and the increase of soil K pool.

关键词： Yujiang County highly productive paddy soils organic C nutrients environmental application

Central gas entropy excess as direct evidence for AGN feedback in galaxy groups and clusters

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Research in Astronomy and Astrophysics 2010年第10期10卷 1013-1022页

作者： Yu Wang Hai-Guang Xu Jun-Hua Gu li-Yi Gu Jing-Ying Wang zhong-li zhang Department of Physics Shanghai Jiao Tong University Shanghai 200240 China Max-Planck-Institute for Astrophysics Karl-Schwarzschild-Str. 1 Postfach 1317 D-85741 Garching Germany

By analyzing Chandra X-ray data of a sample of 21 galaxy groups and 19 galaxy clusters, we find that in 31 sample systems there exists a significant central （R ≤ 10 h^-171 kpc） gas entropy excess （AK0）, which corresponds to = 0.1 - 0.5 keV per gas particle, beyond the power-law model that best fits the radial entropy profile of the outer regions. We also find a distinct correlation between the central entropy excess △K0 and K-band luminosity LK of the central dominating galaxies （CDGs）, which is scaled as △K0 ∝ L K 1.6±04, where LK is tightly associated with the mass of the supermassive black hole hosted in the CDG. In fact, if an effective mass-to-energy conversionefficiency of 0.02 is assumed for the accretion process, the cumulative AGN feedback E AGN feedack=ηMBHc2 yields an extra heating of = 0.5 - 17.0keV per particle, which feedback is sufficient to explain the central entropy excess. In most cases, the AGN contribution can compensate the radiative loss of the X-ray gas within the cooling radius （= 0.002 - 2.2 keV per particle）, and apparently exceeds the energy required to cause the scaling relations to deviate from the self-similar predictions （=0.2 - 1.0 keV per particle）. In contrast to the AGN feedback, the extra heating provided by supernova explosions accounts for = 0.01 - 0.08 keV per particle in groups and is almost negligible in clusters. Therefore, the observed correlation between △K0 and Lx can be considered as direct evidence for AGN feedback in galaxy groups and clusters.

关键词： galaxies active- galaxies clusters general -- X-rays galaxies clus-ters -- (galaxies ) intergalactic medium

Hydrothermal Synthesis,Crystal Structure and Fluorescent Property of a Novel Mo(V) Phosphate [Zn(Mo^v_6P_4O_(31)H_(10))_2(C_4H_(14)N_3)_2]·2C_4H_(13)N_3·8H_2O

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Chinese Journal of Structural Chemistry 2006年第9期25卷 1071-1077页

作者： WEI Chun-Xia CHEN Jian-Xin zhang Zhi-Chun LANTing-Yan HUANG Yuan-Biao li zhong-Shui zhang Wen-Jie College of Chemistry and Materials Science Fujian Normal University Fuzhou 350007 China

A new molybdenum phosphate [Zn（Mo^v6P4O31H10）2（C4H144N3）2].2C4H13N3.8H2O 1 （C4H13N3 = diethylenetriamine） has been synthesized under hydrothermal condition. Single-crystal X-ray diffraction reveals that compound 1 crystallizes in the monoclinic, space group P21/n, a = 13.1679（3）, b = 22.1240（6）, c = 13.6146（3） A, β= 103.4847（7）°, V = 3856.95（16） A^3, C16H90N12O70P8ZnMo12, Mr = 3035.41, Z = 2, Dc = 2.614 g/cm^3, μ = 2.483 mm^-1, F（000） = 2968, S = 1.014, the final R = 0.0196 and wR = 0.0506 for 7486 observed reflections （1 〉 2σ（I））. Compound 1 consists of two identical rings of six edge-sharing MoOt, octahedra interconnected by one ZnO6 octahedron, whereas the PO4 tetrahedra which share their apices with the MoO6, octahedra are only located on one side of each Mo6, ring. The 2-charge of polyanion [Zn（Mo^v6P4O31H10）2]^2- unit is compensated in the crystal by two mono-protonated diethylenetriamines （C4H14N3）^＋. By hydrogen bonding interactions the polyanion of compound 1 is interconnected to form pseudo threedimensional molybdophosphate. Other characterizations by elemental analyses, IR spectrum and fluorescent spectrum are also described.

关键词： molybdenum(V) phosphate hydrothermal synthesis crystal structure fluorescent property

Functional paragangliomas of the urinary bladder:a report of 9 cases

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Chinese Journal of Cancer 2010年第8期29卷 729-734页

作者： Jian-Hua Deng Han-zhong li Yu-Shi zhang Guang-Hua liu Department of Urology Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100730 P. R. China

Background and Objective: Functional paraganglioma of the urinary bladder (FPUB) is a rare tumor. Misdiagnosis of FPUB before operation can lead to serious intraoperative consequences. In this article, we reported our experience in preoperative diagnosis and surgical treatment of FPUB. Methods: Clinical data of nine patients with FPUB treated between June 1985 and January 2009 at Peking Union Medical College Hospital were analyzed. Results: All patients underwent urinary catecholamine (CA) detection, B-ultrasound, CT and/or MRI scan; 5 underwent nailfola microcirculation inspection; 4 underwent 131I-metaiodobenzyl guanidine (MIBG) detection; and 6 underwent 111In-DTPA-Octreotide (OCT) scintiscan. According to the UICC bladder tumor classification, 5 patients had T2, 3 had T3, and 1 had T4 disease. All patients underwent surgical treatment, and 1 received 131I-MIBG therapy. All patients had paroxysmal hypertension and palpitation and six had cold sweat, headache, and dizziness after emphatic urination. The definitive diagnosis was made by histopathologic examination of the removed tumors and was confirmed in 7 cases by the immunohistochemical staining of chromogranin A, Ki-67 and S100 protein. The tumor consisted of discrete aggregates of zellballen cells separated by a network of vascular channels. One patient had metastases in the pelvic lymph nodes, liver and colon. Follow-up ranged from 7 to 289 months (mean, 127.2 ± 34.2). Six of the nine cases reported here were found in the usual locations. One patient had multiple tumors. The catecholamine level was elevated under basal conditions in 8 patients and during endoscopic resection of the tumor in 1 patient; it returned to normal after surgery in 8 patients. Three patients had recurrence and 1 had metastasis following surgery. Conclusions: Early preoperative diagnosis of FPUB is difficult, but it should be suspected in patients with typical tetrad symptoms: headache and micturition syncope, sweating, palpitation an

关键词：膀胱肿瘤手术治疗 S100蛋白儿茶酚胺病理检查临床资料 DTPA 手术切除

X-Ray Properties of the Point Source Population in the Spiral Galaxy NGC 5055 (M63) with Chandra

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Chinese Journal of Astronomy and Astrophysics 2007年第3期7卷 335-344页

作者： Bing Luo Ji-Yao Chen zhong-li zhang Yu Wang Jing-Ying Wang Hai-Guang Xu Department of Physics Fudan University Shanghai 200433 Department of Physics Shanghai Jiao Tong University Shanghai 200240

Using Chandra ACIS S3 data we studied the X-ray properties of low-and highmass X-ray binary populations in the nearby spiral galaxy NGC 5055. A total of 43 X-ray point sources were detected within two effective radii, with 31 sources located on the disk and the rest 12 sources in the bulge. The resolved point sources dominate the X-ray emission of the galaxy, accounting for about 80% of the total counts in 0.3-10keV. From spectral fittings we calculated the 0.3-10.0keV luminosities of all the detected X-ray point sources and found that they span a wide range from a few times 10^37 erg s^-1 to over 10^39 erg s^-1. After compensating for incompleteness at the low luminosity end, we found that the corrected XLF of the bulge population is well fitted with a broken power-law with a break at 1.57-0.20^＋0.21 1038 erg s^-1, while the profile of the disk population＇s XLF agrees with a single powerlaw distribution of slope 0 9-0.06^＋0.07 The disk population is significantly richer at ≥ 2 × 10^38 erg s^- 1 than the bulge population, indicating that the disk may have undergone relatively recent, strong starbursts that significantly increased the HMXB population, although ongoing starbursts are also observed in the nuclear region. Similar XLF profiles of the bulge and disk populations were found in M81. However, in most other spiral galaxies different patterns of spatial variation of the XLF profiles from the bulge to the disk have been observed, indicating that the star formation and evolution history may be more complex than we have expected.

关键词： galaxies individual (NGC 5055)-X-ray binaries-stars luminosity function-stars formation