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Photodynamic inhibitory effects of three perylenequinones on human colorectal carcinoma cell line and primate embryonic stem cell line 被引量:14
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作者 LanMa HongTai +3 位作者 CongLi YuZhang Ze-HuaWang Wei-ZhiJi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第3期485-490,共6页
AIM: To investigate the photodynamic inhibitory effects of Elsinochrome A (EA), Hypocrellin A (HA) and Hypocrellin B (HB) on human colorectal carcinoma Hce-8693 cells and rhesus monkey embryonic stem R366.4 cells, via... AIM: To investigate the photodynamic inhibitory effects of Elsinochrome A (EA), Hypocrellin A (HA) and Hypocrellin B (HB) on human colorectal carcinoma Hce-8693 cells and rhesus monkey embryonic stem R366.4 cells, via inducing apoptosis.METHODS: EA, HA and HB were extracted from metabolites of Hypomyces (Fr) Tul.Sp. R366.4 cells or Hce8693 cells were cultured with different concentrations of EA, HA or HB respectively, irradiated and incubated with fresh medium for 2 h. Cell cycle analysis was performed by flow cytometry (FCM). Data were expressed as means ±SD and analysis of variance and Student' t-test for individual comparisons.RESULTS: The photodynamic bioactivity of EA was first reported in this study. After irradiation for 5 min, 6 min, 10 min or 20 min, photoactivated EA at lower concentrations,which were 10-7 Mol/L, 10-6 Mol/L, 10-5 Mol/L respectively,had no cytotoxic effects on R366.4 ES ceils. Whereas, all of the three perylenequinones could induce apoptosis with a dose-dependent manner when Hce-8693 cells were incubated with photoactivated EA, HA and HB respectively. When Hce-8693 cells were incubated with EA at 10-6 Mol/L and irradiated 5 lin, 6 min, 10 min and 20 min respectively,the rates of EA-induced apoptosis were 0, 0, 13.4 % and 40.5 %. While the rates of HA-induced apoptosis were 29.5 %, 32.0 %, 40.2 % and 22.6 %. And the rates of HBinduced apoptosis were 0, 0, 0 and 13.7 % respectively.Meanwhile, after 10-5 Mol/L treatment, the rates of EA-induced apoptosis were 32.7 %, 19.3 %, 26.4 % and 52.7 %, the rates of HA-induced apoptosis were 47.2 %, 39.1%, 45.2% and 56.6 %, and the rates of HB-induced apoptosis were 0, 0, 20.0 % and 13.9 % respectively.CONCLUSION: EA, HA and HB have significant anti-cancer activity. The order of photodynamic inhibitory effects on tumor cells would be approximately HA>EA>HB. The molecular mechanisms of apoptosis may not be induced by reactive oxygen species and are worth further investigation. 展开更多
关键词 结直肠癌 光力学抑制作用 胚胎干细胞 细胞培养 细胞凋亡
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A New Lignan from Boschniakia himalaica 被引量:16
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作者 LiHuiLIU JianXinPU JingFengZHAO ShuangXiMEI XiaoDongYANG YuBoWANG HongBinZHANG LiangLI 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第1期43-45,共3页
From the ethanol extract of the whole plant of Boschniakia himalaica Hook. f. et. Thoms, a new and two known lignans have been isolated and identified as 7-methoxypinoresino 1, pinoresinol 2, and pinoresinol-O--D-gluc... From the ethanol extract of the whole plant of Boschniakia himalaica Hook. f. et. Thoms, a new and two known lignans have been isolated and identified as 7-methoxypinoresino 1, pinoresinol 2, and pinoresinol-O--D-glucopyranoside 3 respectively. Their structures have been established by spectroscopic methods. 展开更多
关键词 Boschniakia himalaica 7-methoxypinoresinol pinoresinol-O-β-D-glucopyranoside.
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Cucurbitacin and Triterpenoid Glycosides from Hemsleya giganthy 被引量:10
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作者 YaCHEN MingHuaCHIU +1 位作者 KunGU ZhongRongLI 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第5期475-478,共4页
From rhizomes of Hemsleya giganthy collected in Shichuan of China, 16 compounds were isolated. Among them, three compounds (8, 9, 15) are new natural products called Hemslecins G; Hemsgiganosides A and B; respectivel... From rhizomes of Hemsleya giganthy collected in Shichuan of China, 16 compounds were isolated. Among them, three compounds (8, 9, 15) are new natural products called Hemslecins G; Hemsgiganosides A and B; respectively. Their structures were elucidated as 7- hydroxy-23, 24-dihydro-cucurbitacin F-25-O-acetate (8); 3-O-(6-butyl ester-)-b-D-glu- curono- pyranosyl)-oleanolic acid-28-O-a-L-arabinopyranoside(9); 3-O-b-D-glucuropyranosyl oleanolic acid -28-O-b-D-gluco pyranosyl-(16)- b-D-glucopyranoside(15) by spectroscopic and chemical means. 展开更多
关键词 Hemsleya giganthy CUCURBITACEAE Hemslecins G Hemsgiganosides A B. H
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A DISCRETE TIME TWO-LEVEL MIXED SERVICE PARALLEL POLLING MODEL 被引量:6
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作者 GuanZheng ZhaoDongfeng ZhaoYifan 《Journal of Electronics(China)》 2012年第1期103-110,共8页
We present a discrete time single-server two-level mixed service polling systems with two queue types, one center queue and N normal queues. Two-level means the center queue will be successive served after each normal... We present a discrete time single-server two-level mixed service polling systems with two queue types, one center queue and N normal queues. Two-level means the center queue will be successive served after each normal queue. In the first level, server visits between the center queue and the normal queue. In the second level, normal queues are polled by a cyclic order. Mixed service means the service discipline are exhaustive for center queue, and parallel 1-limited for normal queues. We propose an imbedded Markov chain framework to drive the closed-form expressions for the mean cycle time, mean queue length, and mean waiting time. Numerical examples demonstrate that theoretical and simulation results are identical the new system efficiently differentiates priorities. 展开更多
关键词 Polling model PRIORITY TWO-LEVEL Mixed-service Waiting time
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LOCAL INFLUENCE ASSESSMENT IN A MULTIVARIATE t-MODEL WITH RAO'S SIMPLE STRUCTURE 被引量:3
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作者 邹清明 张怀雄 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期179-192,共14页
The local influence analysis is an important problem in statistical inference and some models have been discussed in many literatures This paper deals with the problem of assessing local influences in a multivariate t... The local influence analysis is an important problem in statistical inference and some models have been discussed in many literatures This paper deals with the problem of assessing local influences in a multivariate t-model with Rao's simple struc-ture(RSS). Based on Cook's likelihood displacement, the effects of some minor perturbation on the statistical inference is assessed. As an application, a common covariance-weighted perturbation is thoroughly discussed. 展开更多
关键词 Multivariate t-model Rao's simple structure ω-model likelihood displacement MLE
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HAUSDORFF MEASURES OF A CLASS OF SIERPINSKI CARPETS 被引量:4
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作者 ChenDan YangXiaoling 《Analysis in Theory and Applications》 2004年第2期167-174,共8页
In this paper, a lemma as a new method to calculate the Hausdorff measure of fractal is given. And then the exact values of Hausdorff measure of a class of Sierpinski sets which satisfy balance distribution and dimens... In this paper, a lemma as a new method to calculate the Hausdorff measure of fractal is given. And then the exact values of Hausdorff measure of a class of Sierpinski sets which satisfy balance distribution and dimension ≤ 1 are obtained. 展开更多
关键词 FRACTAL sierpinski carpet Hausdorff measure balance distribution
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Synthesis of Novel Benzoylphenylurea Chitin Inhibitors from Chlorothalonil 被引量:4
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作者 JunLIN ShengJiaoYAN +3 位作者 DeShouMAO RongXU LiJuanYANG FuChuLIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第12期1219-1222,共4页
Twenty-six novel benzoylphenylurea chitin inhibitor derivatives have been synthesized in over 30~50% yield from chlorothalonil 1 via sequential fluorine exchange, aminolysis, hydrolysis, decarboxylation and acylation ... Twenty-six novel benzoylphenylurea chitin inhibitor derivatives have been synthesized in over 30~50% yield from chlorothalonil 1 via sequential fluorine exchange, aminolysis, hydrolysis, decarboxylation and acylation reactions. 展开更多
关键词 Benzoylphenylureas chitin inhibitor chlorothalonil.
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Population dynamics of Trichoderma species in the rhizosphere of tobac co and four species form China 被引量:2
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作者 YUZe-fen ZHANGKe-qin 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2004年第4期468-468,共1页
To study the effect of tobacco growth on Trichoderma population, we in vestigated the occurrence of Trichoderma species in the rhizosphere of tob acco plant during the period from transplanting (June) to harvesting (O... To study the effect of tobacco growth on Trichoderma population, we in vestigated the occurrence of Trichoderma species in the rhizosphere of tob acco plant during the period from transplanting (June) to harvesting (October) and measured relative environmental factors. Eleven species of Trichoderma we re isolated, among which T.harzianum, T.viride, T.hamatum, T.atroviride, T.lo ngibrachiatum, T.virens, T.koningii were identified, other four species Ty1, Ty2, Ty3, Ty4 are new species. Of the species which occurred at high frequencies , T.harzianum and T.hamatum were most abundant in the July and T. viride in the August. The occurrence of the above three abundant species corr elates significantly with the developmental phase of tobacco and correlates appa rently with the soil moisture content, but not with the temperature. For the oth er eight species, no obvious correlation was found between the above factors and them. Based on nucleotide sequences of the internal transcribed spacer (ITS) regions of the rDNA cluster (ITS1and 2) and partial sequences of translation elongation f ac tor 1-alpha (tef1a), phylogenetic position of four new species was determined. Ty2 is additions to Trichoderma section and Ty3.Ty9.Ty10 are additions to sec tion Pachybasium. 展开更多
关键词 群体动力学 根际 植物 种类 真菌 木霉属
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Influence of NaCl Deposition on Atmospheric Corrosion of A3 Steel 被引量:3
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作者 QingQU ChuanweiYAN 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2002年第6期552-555,共4页
Regularity of the initial atmospheric corrosion of A3 steel in the presence of NaCI was investigated. The results showed that NaCI can accelerate the corrosion of A3 steel. Dry mass gain of A3 steel in the presence of... Regularity of the initial atmospheric corrosion of A3 steel in the presence of NaCI was investigated. The results showed that NaCI can accelerate the corrosion of A3 steel. Dry mass gain of A3 steel in the presence of NaCI deposition increases with the exposure time, which can be correlated by using exponential decay function. The relationship between dry mass gain and amount of NaCI deposition at a certain exposure time follows a quadratic function. More amount of NaCI deposition will slow down the corrosion rate to some extent after exposure for a certain time. SEM/EDAX was used to characterize the corrosion surface and products. The surfaces of the NaCI treated A3 steel were obviously uneven, and some tiny crevices appear in the corrosion products that could help O2 transmit to the inner layer. The amount of oxygen in atomic percentage in the corrosion products increases with the amount of NaCI deposition. 展开更多
关键词 A3 steel Atmospheric corrosion CORROSION NACL
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MATHEMATICAL MODEL FOR ACCESS MODE OF CONTENTION-COLLISION CANCELLATION IN A STAR LAN 被引量:5
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作者 LuZhaoyi SunLijun 《Journal of Electronics(China)》 2004年第1期37-47,共11页
I type system model of CCCAM(Contention-Collision Cancellation Access Mode) is studied through mathematical modelling and simulation. There are two innovations: (1) in the process of mathematical modelling, the instan... I type system model of CCCAM(Contention-Collision Cancellation Access Mode) is studied through mathematical modelling and simulation. There are two innovations: (1) in the process of mathematical modelling, the instance of 'serving customers unsuccessfully' is taken into account; (2) the time at which customers depart after having been served successfully are chosen to be the embedded point, thereby 'free period' is introduced reasonably. So the mathematical modelling and analysis result in this paper are significant for application of wire star LAN and wireless star LAN. 展开更多
关键词 Multi-Star LAN Contention-Collision Cancellation Access Mode (CCCAM) Access mode Mathematical modelling
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Antibacterial Activities of Neolignans Isolated from the Seed Endotheliums of Trewia nudiflora 被引量:4
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作者 LIGuo-Hong ZHAOPei-Ji +1 位作者 SHENYue-Mao ZHANGKe-Qin 《Acta Botanica Sinica》 CSCD 2004年第9期1122-1127,共6页
Five neolignans including four new ones were obtained from the seed endotheliums of Trewia nudiflora L. Their structures were determined to be 9'-methyl americanol A(1), 9'-methyl isoamericanol A(2), 9'-et... Five neolignans including four new ones were obtained from the seed endotheliums of Trewia nudiflora L. Their structures were determined to be 9'-methyl americanol A(1), 9'-methyl isoamericanol A(2), 9'-ethyl americanol A(3), 9'-butyl americanol A(4), and americanin (5). Two acetylated products 3,4-diacetyl americanin (5a) and 3,4,9-triacetyl americanin (5b) had been prepared from compound 5. All of these compounds were investigated on antibacterial assays when carbenicillin sodium, streptomycin sulfate and rifampicin were used as positive controls. Compounds 4 and 5 exhibited antibacterial activities against gram-positive bacterium Staphylococcus aureus and gram-negative bacterium Mycobacterium tuberculosis at the minimum inhibitory concentrations (MIC) of 50μg/mL and 100μg/mE respectively, but 5a and 5b did not exhibit antibacterial activity at 200μg/disk. 展开更多
关键词 新木脂素 种皮 抗菌活性 大戟科 革兰氏阳性菌
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A New Iridoid Glucoside from Lagotis yunnanensis 被引量:2
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作者 XiaoDongYANG ShuangXiMEI +3 位作者 JingFengZHAO GanPengLI HongBinZHANG LiangLI 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第9期936-938,共3页
Phytochemical investigation of Lagotis yunnanensis led to the isolation and identification of a new iridoid glucoside 1, named as 10-O-(3,4-dimethoxy-(E)-cinnamoyl)aucubin. Its structure was elucidated by spectroscopi... Phytochemical investigation of Lagotis yunnanensis led to the isolation and identification of a new iridoid glucoside 1, named as 10-O-(3,4-dimethoxy-(E)-cinnamoyl)aucubin. Its structure was elucidated by spectroscopie methods. 展开更多
关键词 Lagotis yunnanensis iridoid glucoside 10-O-(3 4-dimethoxy-(E)-cinnamoyl)aucubin.
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Oscillation of Second-order Delay Differential Equation 被引量:2
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作者 YINFu-qi LIYong-kun 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第1期30-34,共5页
By using some differential inequality, a second-order delay differential equation(r(t)x′(t))′ + p(t)x(q(t)) = 0has been investigated and some necessary condition for this equation has a nonoscillatorysolution and so... By using some differential inequality, a second-order delay differential equation(r(t)x′(t))′ + p(t)x(q(t)) = 0has been investigated and some necessary condition for this equation has a nonoscillatorysolution and some sufficient condition which ensures that all of the solutions of the aboveequation are oscillatory are obtained. 展开更多
关键词 differential equation DELAY OSCILLATION differential inequality
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Hydrothermal Synthesis and Structure of a Novel 1-D Mn(II) Compound with Carboxlyto and Imidazole Ligands 被引量:2
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作者 WANGYu-De WUXing-Hui +1 位作者 ZENGQing-Xin YAOYou-Wei 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第6期641-644,共4页
A novel manganiferous polymeric complex [(imid)2(ta)Mn0.5]n (imid = imidazole, ta = terephthalato) was synthesized by the hydrothermal reaction of MnO2, terephthalic acid, imidazole, and H2O. Structure analysis indica... A novel manganiferous polymeric complex [(imid)2(ta)Mn0.5]n (imid = imidazole, ta = terephthalato) was synthesized by the hydrothermal reaction of MnO2, terephthalic acid, imidazole, and H2O. Structure analysis indicates that the compound crystallizes in the triclinic system, space group P1, with a = 8.1500(16), b = 8.5100(17), c = 9.0500(18) ?, α = 72.77(3), β = 65.50(3), γ = 77.22(3)o, V = 542.02(19) ?3, Z = 2, Dc = 1.505 g/cm3, F(000) = 253, Mr = 245.69, μ(MoKα) = 0.655 mm-1, R = 0.0733 and wR = 0.1703 for 1673 observed reflections (I > 2σ(I)). The compound is characteristic of a zigzag chain-like framework built up of ta bridge and (Imid)4Mn group. The 1-D frameworks are held together by H-bonds between the dangling N–H donors from imid and O acceptors from ta. 展开更多
关键词 crystal structure terephthalic acid IMIDAZOLE hydrothermal synthesis
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Recent advance of nematophagous fungi from China and with a special case on Clonostachys rosea (Gliocladium roseum) 被引量:1
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作者 ZHANGKe-qin ZHAOMing-lan 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2004年第4期389-389,共1页
China is one of the twelve prolific biological diversity countries in the world, and nematophagous fungol resources are very abundant. In this paper, the research advance of nematophagous fungi is discussed from six a... China is one of the twelve prolific biological diversity countries in the world, and nematophagous fungol resources are very abundant. In this paper, the research advance of nematophagous fungi is discussed from six aspects: resources introduction, biology of nematophagous fungi, the application of biocontrol agents, fungistsis in soils, research on nematicidal metabolites and molecular biology on nematophagous fungi. Concerning Clonostachys rosea, the alkaline protease (designated Lmz1) was purified from supernatant of C. rosea which showed a molecular mass of 33 kDa, pI of pH 10.5, optimum temperature of 55- 60 ℃. and optimum pH between 11.0-12.0. N-terminal sequence of Lmz1 was determined by electoblotting enzyme protein to PVDF membrane as NH2-A-T-Q-S-N-A-P-?-?-?. The degenerate primer was designed according to terminal sequence for cDNA gene encoding mature protein of Lmz1 by 3’RACE system for rapid amplification of cDNA ends. To express successfully a fungal alkaline protease (Lmz1) in a high level expression system. The specific primers with EcoRI recognition site and extra bases were designed. The cDNA gene encoding mature protease (Lmz1) was amplified with high fidelity pfu DNA polymerase and specific primers against total cDNA population of C. rosea. The recombinant expression vector contain desired DNA fragment was correctly constructed and introduced into yeast host Pichia pastoris GS115 by electroporation. The recombinant alkaline protease was characterized by protease activity, PCR amplification against yeast total DNA, ELISA and western blotting. It demonstrated a molecular mass of 42 kDa based on blot analysis. The expression level of Lmz1 was approximately 9 mg/mL by UV spectrophotometric method. 展开更多
关键词 食线虫真菌 中国 粘帚霉属 CDNA 基因 表达
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Two New Iridoid Glucosides from Lagotis yunnanensis 被引量:1
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作者 XiaoDongYANG JingFengZHAO ShuangXiMEI JianXinPU HongBinZHANG LiangLI 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第1期49-51,共3页
Two new iridoid glucosides 1 and 2, 10-O-(3, 4-dimethoxy-(E)-cinnamoyl)catalpol and 10-O-(3, 4-dimethoxy-(Z)-cinnamoyl)catalpol, were isolated from Lagotis yunnanensis. Their structures were elucidated by spectroscop... Two new iridoid glucosides 1 and 2, 10-O-(3, 4-dimethoxy-(E)-cinnamoyl)catalpol and 10-O-(3, 4-dimethoxy-(Z)-cinnamoyl)catalpol, were isolated from Lagotis yunnanensis. Their structures were elucidated by spectroscopic methods. 展开更多
关键词 Lagotis yunnanensis iridoid glucosides 10-O-(3 4-dimethoxy-(E)-cinnamoyl)catalpol 10-O-(3 4-dimethoxy-(Z)-cinnamoyl)catalpol.
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New Acetylated Flavonol Glycosides from Knoxia corymbosa 被引量:2
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作者 YuBoWANG JianXinPU +5 位作者 HaiYing,REN JingFengZHAO ShuangXiMEI ZiYanLI HongBinZHANG LiangLI 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第12期1268-1270,共3页
Two new diacetylated flavonol glycosides, kampferol-3-O--3? 6?diacetylglucopyrano- side and quercetin-3-O--3? 6?diacetylglucopyranoside were isolated from knoxia corymbosa. Their structures were elucidated by spectro... Two new diacetylated flavonol glycosides, kampferol-3-O--3? 6?diacetylglucopyrano- side and quercetin-3-O--3? 6?diacetylglucopyranoside were isolated from knoxia corymbosa. Their structures were elucidated by spectroscopic evidents. 展开更多
关键词 Acetylated flavonol glycosides Knoxia corymbosa.
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Modern Sedimentation of Phosphorus and Its Microbial Decomposition and Concentration: An Example from Dianchi Lake, Yunnan, China 被引量:1
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作者 XIAXuehui DONGYEMoxing ZHANGZhuo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期763-767,共5页
Dianchi Lake is one of the lakes with the richest phosphorus source in the world, in which the P2O5 content in the bottom sediments reaches averagely 0.51 wt % and maximally 1.92%. Studies indicate that this: extremel... Dianchi Lake is one of the lakes with the richest phosphorus source in the world, in which the P2O5 content in the bottom sediments reaches averagely 0.51 wt % and maximally 1.92%. Studies indicate that this: extremely P-rich state is attributed mainly to the large volume (as high as hundred thousands of tons) of phosphatic matter coming into the lake as many rivers feeding the lake pass through a vast area of phosphate-mining districts, which then undergo weathering and particularly some human activities, including waste water discharge. When phosphatic matter enters the lake, its grained parts are firstly decomposed by phosphorus-decomposing bacteria, and finally accumulated in some geographically special parts of the lake, such as a bay area where water flow is much more slower than elsewhere in the lake. With the involvement of phosphorus-concentrating bacteria, the accumulated phosphates in the bottom sludge ultimately form phosphate minerals through deep-burial diagenesis. 展开更多
关键词 phosphorus circulation and enrichment microbial mineralization Dianchi Lake YUNNAN China
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Rate Constants for the Reactions of NO_3~.and SO_4^(._) Radicals with Oxalic Acid and Oxalate Anions in Aqueous Solution 被引量:1
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作者 XiKunYANG JiaQiangWANG TieDangWANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第5期583-586,共4页
Rate constants for the reactions of NO3 and SO4 radicals with oxalic acid and oxalate anions in aqueous solution have been measured using pulse radiolysis and laser flash photolysis.
关键词 NO3 SO4 OXALATES aqueous phase rate constants.
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Two New ent-Kauranoids from Isodon sculponeata 被引量:1
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作者 BeiJIANG HuiYANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第11期1083-1086,共4页
Two new ent-kaurane diterpenoids, sculponeatins L (1) and M (2), were isolated from the EtOAc extract of Isodon sculponeata. Their structures were elucidated by spectroscopic evidences. The cytotoxicities of 1 and 2... Two new ent-kaurane diterpenoids, sculponeatins L (1) and M (2), were isolated from the EtOAc extract of Isodon sculponeata. Their structures were elucidated by spectroscopic evidences. The cytotoxicities of 1 and 2 against human tumor cells K562 and T24 were tested. 展开更多
关键词 Isodon sculponeata LABIATAE ent-kauranoids sculponeatins L and M.
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