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1Treatment of soybean wastewater by a wild strain Rhodobacter sphaeroides and to produce protein under natural conditions显示文摘The conventional treatment method of soybean wastewater is expensive and generates waste sludge that requires further handling.Purple nonsulfur bacteria(PNSB)wastewater treatment is a clean technology and can generate single cell protein while degrading pollutants.A wild strain of PNSB,Rhodobacter sphaeroides Z08,was isolated from local soil and was used to treat soybean wastewater.To develop a cost-effective process,the work was performed under natural conditions without artificial light,aeration,nutrients addition,or pH and temperature adjustment.The results showed that the wild strain Rhodobacter sphaeroides Z08 could grow well under natural conditions.The growth curve showed two quickgrowth periods and a turning point.The Z08 treatment of soybean wastewater was zero order reaction and COD reduction was 96%after 10 d.The major byproducts of the process were C2-C5 organic acids,predominantly butyric acid.No alcohol was found in the effluent.The initial COD/bacterial-mass ratio(F/M)had a significant effect on soybean wastewater treatment efficiency.When the initial F/M was lower than 10 mg-COD/mg-bacteria,a sufficient amount of time to achieve 90%of COD reduction was only three days.The Z08 biomass yield was 0.28 g·g^(–1),and the bacterial protein content was 52%.Junguo HE Guangming ZHANG Haifeng LU 2010Frontiers of Environmental Science & Engineering2010,4,3:20
2The development of China's Yangtze River Economic Belt:how to make it in a green way?显示文摘The Yangtze River is one of the largest and longest rivers in Asia.The river originates in the Tibet-Qinghai Plateau(headwater reach),passes through the mountainous provinces of Sichuan,Yunnan and Chongqing(upper reach),flows into the Central Plain(middle reach)and Lower Plain(lower reach),and finally empties into the East China Sea in Shanghai(estuary).The Yangtze River Economic Belt(YREB;Fig.1)has a surface area of 2.1Yushun Chen Shuanghu Zhang Desheng Huang Bai-Lian Li Junguo Liu Wenjin Liu Jing Ma Fang Wang Yong Wang Shengjun Wu Yegang Wu Jinyue Yan Chuanbo Guo Wei Xin Hao Wang 2017Science Bulletin2017,62,9:20
3Competitive binding of postsynaptic density 95 and Ca^(2+)-calmodulin dependent protein kinase II to N-methyl-D-aspartate receptor subunit 2B in rat brain显示文摘AIM: To investigate the interactions among postsynaptic density 95 (PSD-95), Ca2+-calmodulin dependent protein kinase IIα (CaMKIIα), and N-methyl-D-aspartate receptor subunit 2B (NR2B) during ischemia and reperfusion in hippocampus of rats. METHODS: Brain ischemia was induced by four-vessel occlusion procedure in rats. Immu- noprecipitation and immunoblotting were performed to study the interactions and phosphorylation of proteins. The association-dissociation of PSD-95 and CaMKIIα to and from N-methyl-D-aspartate (NMDA) receptor induced by ischemia and reperfusion and the effects of 1-[N,O-bis-(5-isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4-phenyl-pip- erazine (KN-62, a selective inhibitor of CaMKII) on these protein interactions were investigated. Coimmuno- precipitation and immunoblotting were performed for the studies of interactions among proteins. RESULTS: The alternations of the binding level of PSD-95 and CaMKIIα to NR2B during ischemia and reperfusion demonstrated the negative correlation to each other. Pre-administration of KN62 through both cerebral ventricles inhibited the 10 min ischemia-induced increase of the binding of PSD-95 to NR2B and, on the contrary, promoted the binding of CaMKIIα to NR2B. CONCLUSION: PSD-95 competes with CaMKII to bind to NR2B during ischemia and reperfusion in rat hippocampus.Fan-jieMENG JunGUO BoSONG Xue-boYAN Guang-yiZHANG 2004Acta Pharmacologica Sinica2004,25,2:12
4Synthesis, characterization and application of a dispersant based on rosin for coal-water slurry显示文摘A rosin derivative and maleopimaric acid diethanolamide(MAD), was synthesized, characterized by FTIR and1 H NMR, and applied as dispersant for the coal-water slurry(CWS) prepared from Chinese Shenfu coal. The CWS application performance investigation shows that the MAD dispersant has better abilities in reducing CWS viscosity and stabilizing the slurry than a commercial dispersant—sulfonated naphthalene-formaldehyde condensate(SNF). The physicochemical property investigation of the two tested dispersants shows that the adsorption amount of the MAD at coal-water interface is much larger than that of SNF, and the MAD has better wetting property than the SNF on the coal surface. It indicated that the excellent capabilities of MAD are related to the adsorption mode of standing upright on the coal surface. Based on the above, the mechanism of dispersion and stabilization of the CWS prepared from MAD dispersant is presented.Li Junguo Zhang Guanghua Shang Ting Zhu Junfeng 2014International Journal of Mining Science and Technology2014,24,5:11
5Intratumoral Expression of MIP-1β Induces Antitumor Responses in a Pre-Established Tumor Model through Chemoattracting T Cells and NK Cells显示文摘Direct intratumoral introduction of therapeutic or regulatory genes is a developing technology with potential application for cancer gene therapy. Macrophage inflammatory protein-1 beta (MIP-1β) is a chemokine which can chemoattract immune cells such as T cells. In the present study, murine colorectal adenocarcinoma CT26 cells were transfected with a recombinant adenovirus (AdhMIP-1β) carrying the human MIP-1β gene. 24 h post-transfection, hMIP-1β levels reached approximately 980 pg/ml in supernatants of 106 hMIP-1β-transfected CT26 cells. Moreover, the supernatants exhibited chemotactic activity for CD8+ T cells, CD4+ T cells, NK cells and immature DCs. Intratumoral injection of AdhMIP-1β significantly inhibited tumor growth and prolonged the survival time of tumor-bearing mice. Intratumoral hMIP-1β gene transfer also induced powerful tumor- specific CTL responses in vivo. The therapeutic effects of hMIP-1β gene therapy were greatly reduced following in vivo depletion of both CD4+ and CD8+T cells, but were unaffected by depletion of single T cell subsets. Immune cell depletion experiments also revealed that NK cells played an important role in hMIP-1β-induced antitumor responses. These results suggest that intratumoral expression of hMIP-1β has the potential effect to induce host antitumor immunity and may prove to be a useful form of cancer gene therapy.XiaolingLuo YizhiYu AnminLiang YuanXie ShuxunLiu JunGuo WenyaWang RunziQi HuazhangAn MinghuiZhang HongmeiXu ZhenhongGuo XuetaoCao 2004Cellular & Molecular Immunology2004,1,3:8
6Identification of quantitative trait loci for the dead leaf rate and the seedling dead rate under alkaline stress in rice显示文摘The quantitative trait loci (QTLs) for the dead leaf rate (DLR) and the dead seedling rate (DSR) at the different rice growing periods after transplanting under alkaline stress were identified using an F2:3 population, which included 200 individuals and lines derived from a cross between two japonica rice cultivars Gaochan 106 and Changbai 9 with microsatellite markers. The DLR detected at 20 days to 62 days after transplanting under alkaline stress showed continuous normal or near normal distributions in F3 lines, which was the quantita- tive trait controlled by multiple genes. The DSR showed a continuous distribution with 3 or 4 peaks and was the quantitative trait con- trolled by main and multiple genes when rice was grown for 62 days after transplanting under alkaline stress. Thirteen QTLs associated with DLR were detected at 20 days to 62 days after transplanting under alkaline stress. Among these, qDLR9-2 located in RM5786?RM160 on chromosome 9 was detected at 34 days, 41 days, 48 days, 55 days, and 62 days, respectively; qDLR4 located in RM3524?RM3866 on chromosome 4 was detected at 34 days, 41 days, and 48 days, respectively; qDLR7-1 located in RM3859?RM320 on chromosome 7 was detected at 20 days and 27 days; and qDLR6-2 in RM1340-RM5957 on chromosome 6 was detected at 55 days and 62 days, respectively. The alleles of both qDLR9-2 and qDLR4 were derived from alkaline sensitive parent 'Gaochan106'. The alleles of both qDLR7-1 and qDLR6-2 were from alkaline tolerant parent Changbai 9. These gene actions showed dominance and over dominance primarily. Six QTLs associated with DSR were detected at 62 days after transplanting under alkaline stress. Among these, qDSR6-2 and qDSR8 were located in RM1340?RM5957 on chromosome 6 and in RM3752?RM404 on chromosome 8, respectively, which were asso- ciated with DSR and accounted for 20.32% and 18.86% of the observed phenotypic variation, respectively; qDSR11-2 and qDSR11-3 were located in RM536?RM479 and RM2596?RM286 on chromosome 11, respectively, which were associated with DSR explaining 25.85% and 15.41% of the observed phenotypic variation, respectively. The marker flanking distances of these QTLs were quite far ex- cept that of qDSR6-2, which should be researched further.Dongling Qi Guizhen Guo Myung-chul Lee Junguo Zhang Guilan Cao Sanyuan Zhang Seok-cheol Suh Qingyang Zhou Longzhi Han 2008Journal of Genetics and Genomics2008,35,5:8
7Combined biologic aerated filter and sulfur/ceramisite autotrophic denitrification for advanced wastewater nitrogen removal at low temperatures显示文摘联合生物学的充气过滤器(BAF ) 和 sulfur/ceramisite-based 的一个创新先进废水处理过程为氮的可靠移动的自造营养物质的 denitrification (大量) 在这份报纸被建议。在大量反应堆, ceramisite 被用作过滤器和 Ca (HCO < 潜水艇 class= “ a-plus-plus ” > 3 ) 2 被用于供应碱度和碳来源。BAF 大量被用来对待第二等的处理自河。这进程的性能被调查,并且氮移动上的温度的影响被学习。结果证明联合系统甚至在低温度在氮移动是有效的(8 ?= 瑥 ?  ? ,Tian WAN Guangming ZHANG Fcngwci DU Junguo HE Pan WU 2014Frontiers of Environmental Science & Engineering2014,8,6:6
8Dissecting role of regulatory factors in NF-κB pathway with siRNA显示文摘NF-κB, a family of related transcription factors, has been a focus of intense scientific research during the past decade. Multiple stimuli, both extracellular and intracellular, lead to its activation. The NF-κB pathway regulates expression of a diverse array of genes involved in different biological processes. Various pathological states are characterized by the dysregulated NF-κB pathway. Recently, NF-κB activation has been connected with multiple aspects of oncogenesis and serves as an important mechanism to regulate cell survival in response to chemotherapy by activating different genes that inhibit apoptosis. Several methods of inhibiting NF-κB activation, such as antisense oligonucleotides, proteosome inhibitors and RNA interference (RNAi) are currently under investigation. RNAi represents a powerful tool to better define the role of specific genes in different signal transduction pathways and has recently been used to define the function of genes that regulate the NF-κB pathway. This review discusses the emerging role of RNAi to dissect the function of regulatory factors in the NF-κB pathway and its potential use as a targeted therapy.JunGUO Yu-caiFU CarlosRBECERRA 2005Acta Pharmacologica Sinica2005,26,7:6
9Heme oxygenase-1 alleviates ischemia/reperfusion injury in aged liver显示文摘AIM: To investigate if ischemia/reperfusion (I/R) injury in aged liver could be alleviated by heme oxygenase-1 (HO-1).METHODS: Three groups of SD rats (16 mo old) were studied. Group 1: control donors received physiological saline 24 h before their livers were harvested; group 2: donors were pretreated with hemih 24 h before their livers were harvested; and group 3: donors received hemin 24 h before their livers were harvested and zinc protoporphyrin (ZnPP,HO-1 inhibitor) was given to recipients at reperfusion. The harvested livers were stored in University of Wisconsin solution (4 ℃) for 6 h, and then transplanted to syngeneic rats. Serum glutamic oxaloacetic transaminase (SGOT),apoptotic cells, and apoptotic gene were measured 3, 6,12, 24, 48 h after reperfusion. We measured the apoptotic index by TUNEL, determined the expression of antiapoptotic Bcl-2 and proapoptotic (caspase-3) gene products by Western blot.RESULTS: After 3, 6, 12, 24, and 48 h of reperfusion, the SGOT levels (584.4±85.8 u/L, 999.2±125.2 u/L, 423.4±161.3u/L, 257.8±95.8 u/L, and 122.4±26.4 u/L) in hemin group were significantly (all P<0.05) lower than those in saline group (1082.2±101.2 u/L, 1775.2±328.3 u/L, 840.4±137.8 u/L,448.6±74.3 u/L, and 306.2±49.3 u/L). Liver HO-1 enzymatic activity correlated with beneficial effects of hemin and deleterious effects of adjunctive ZnPP treatment. Markedly less apoptotic (TUNEL+) liver cells 3, 6, 12, 24, and 48 h after reperfusion (5.16±0.73, 10.2±0.67, 9.28±0.78, 7.14±1.12,and 4.78±0.65) (P<0.05) could be detected in hemin liver grafts, as compared to controls (7.82±1.05, 15.94±1.82,11.67±1.59, 8.28±1.09, and 6.36±0.67). We detected the increased levels of Bcl-2 (1.5-fold) expression and compared with saline controls. These differences were most pronounced at 12 h after transplantation. In contrast, an active form of proapoptotic caspase-3 (p20) protein was found to be 2.9-fold lower at 24 h in hemin-pretreated group, as compared to saline liver transplant controls.CONCLUSION: HO-1 overexpression can provide potent protection against cold I/R injury. This effect depends, at least in part, on HO-1-mediated inhibition of antiapoptotic mechanism.Xue-HaoWang KeWang FengZhang Xiang-ChengLi JunLi Wei-De JunGuo Xiao-FengQian YeFan 2005World Journal of Gastroenterology2005,11,5:6
10Reverse micelles extraction ofnattokinase:From model system to real system显示文摘Nattokinase is a novel fibrinolytic en- zyme, which is homologous to Subtilisin Carlsberg. In this paper, Subtilisin Carlsberg was taken as a model protein of nattokinase. Effects of pH, ionic strength, concentration of isopropanol on the extraction of Subtilisin Carlsberg with AOT/isooctane reverse mi- celles system were investigated. Further, the process of reverse micelles extraction of nattokinase from fermentation broth was studied. By taking the reverse micelles of AOT/isooctane as extractant to perform a full extraction cycle, it was found that about eighty percent of the total activity of nattokinase in the fer- mentation broth could be recovered and the purifica- tion factor was about 2.5. Homologous protein could be reasonably used as model protein of a target protein.LIU Junguo XING Jianmin CHANG Tianshi LIU Huizhou 2006Chinese Science Bulletin2006,51,7:4
11The influence of intimacy on the ’iterative reactions’ during OX-ZEO process for aromatic production显示文摘The oxide-zeolite process provides a promising way for one-step production of aromatics from syngas,whereas the reasons for the dramatic effect of intimacy between oxide and zeolite in the composite catalyst on the product selectivity are still unclear. In order to explore the optimal intimacy and the essential influence factors, ZnCrOxcombined with ZSM-5 are employed to prepare the composite catalysts with different distances between the two components by changing the mixing methods. An aromatic selectivity of 74%(with CO conversion to be 16%) is achieved by the composite catalyst when the intimacy is in the range of nanometer. A so-called ‘iterative reactions’ mechanism of intermediates over oxides is then proposed and studied: the intermediate chemical can undergo a hydrogenation reaction on oxide.So the shorter the intermediates stay on oxide, the more of chance for C-C coupling takes place on zeolite to form aromatics. Moreover, the aero-environments of reaction is found to impact on the extent of iterative reaction as well. Therefore, when the intimacy between the two components changes, the extent of iterative reactions vary, resulting in alteration of product distribution. This work provides new insight in understanding the mechanisms during the complex process of OX-ZEO composite catalysis and sheds light to the design of a high-yield catalyst for synthetization of aromatics from syngas.Xiaoli Yang Ting Sun Junguo Ma Xiong Su Ruifeng Wang Yaru Zhang Hongmin Duan Yanqiang Huang Tao Zhang 2019Journal of Energy Chemistry2019,28,8:4
12Microstructures and high-temperature self-lubricating wearresistance mechanisms of graphene-modified WC–12Co coatings显示文摘To reduce the friction coefficient of cobalt-cemented tungsten carbide(WC–12Co)wear-resistant coatings,graphene was compounded into WC–12Co powder via wet ball milling and spray granulation.Selflubricating and wear-resistant graphene coatings were prepared via detonation gun spraying.The presence,morphologies,and phase compositions of graphene in the powders and coatings that are obtained through different powder preparation processes were analyzed.The analysis was performed using the following technologies:energy-dispersive X-ray-spectroscopy(EDXS),scanning electron microscopy(SEM),transmission electron microscopy(TEM),and Raman spectroscopy.The mechanical properties of the coatings were studied using a microhardness tester and a universal drawing machine.The friction and wear properties of the coatings were studied using an SRV-4 friction and wear tester.The results showed that the graphene content in the WC–12Co coating modified with graphene was higher than that without modification;graphene was embedded in the structure in a transparent and thin-layer state.The adhesive strength of this coating at approximately 25°C was approximately 60.33 MPa,and the hardness was approximately 984 HV0.3.After high-temperature treatment,the adhesive strength and hardness of the graphene oxide(GO)/WC–12Co coating decreased slightly(the lowest adhesive strength of 53.16 MPa was observed after treatment at 400°C,and the lowest hardness of approximately 837 HV0.3 was observed after treatment at 300°C).Compared to the friction coefficient(0.6)of the WC–12Co coating obtained at room temperature,the friction coefficient of the GO/WC–12Co coating was decreased by approximately 50%of that value.The graphene-modified coating was continuously exposed to the wear tracks on the surface of the contacting materials during friction,and a lubricating film was formed in the microareas in which the wear tracks were present.The coating exhibited improved self-lubricating and wear-resistant effects compared to the unmodified WC–12Co coating.The results of this study demonstrated that graphene could be effective in self-lubrication and wear-reduction in a temperature range of 100–200°C,as a friction coefficient of 0.3 was maintained.Haoliang TIAN Changliang WANG Mengqiu GUO Yongjing CUI Junguo GAO Zhihui TANG 2021Friction2021,9,2:4
13Retinal projection head-mounted display显示文摘Junguo LIN Dewen CHENG Cheng YAO Yongtian WANG 2017Frontiers of Optoelectronics2017,10,1:4
14A Storm Surge Intensity Classification Based on Extreme Water Level and Concomitant Wave Height显示文摘Storm surge is one of the predominant natural threats to coastal communities. Qingdao is located on the southern coast of the Shandong Peninsula in China. The storm surge disaster in Qingdao depends on various influencing factors such as the intensity, duration, and route of the passing typhoon, and thus a comprehensive understanding of natural coastal hazards is essential. In order to make up the defects of merely using the warning water level, this paper presents two statistical distribution models(Poisson Bi- variable Gumbel Logistic Distribution and Poisson Bi-variable Log-normal Distribution) to classify the intensity of storm surge. We emphasize the joint return period of typhoon-induced water levels and wave heights measured in the coastal area of Qingdao since 1949. The present study establishes a new criterion to classify the intensity grade of catastrophic storms using the typhoon surge estimated by the two models. A case study demonstrates that the new criterion is well defined in terms of probability concept, is easy to implement, and fits well the calculation of storm surge intensity. The procedures with the proposed statistical models would be useful for the disaster mitigation in other coastal areas influenced by typhoons.DONG Sheng GAO Junguo LI Xue WEI Yong WANG Liang 2015Journal of Ocean University of China2015,14,2:4
15A survey on chemical and microbiological composition of kurut, naturally fermented yak milk from Qinghai in China显示文摘Heping Zhang Jie Xu Junguo Wang Menghebilige Tiansong Sun Haiping Li Mingruo Guo 2007Food Control2007,,6:3
16Infl uencing Mechanism and Interaction of Muscovite on Thermal Decomposition of Ammonium Polyphosphate显示文摘The interaction mechanism and phase evolution of ammonium polyphosphate(APP)mixed with muscovite(APP/muscovite)were studied by TG,XRD and SEM,respectively,during heating.When the temperature is not higher than 300 ℃,muscovite has no effect on the thermaldecomposition of APP,and the initialdecomposition temperature of APP/muscovite at 283 ℃ is basically the same as the APP at 295 ℃,and the main thermaldecomposition products are polyphosphoric acid and NH_4H_2PO_4 at 300 ℃.The polyphosphoric acid,the decomposition products of APP,can enable K and Siout of muscovite and interact with muscovite chemically to generate Al_2O_3·2SiO_2,α-SiO_2 and phosphates(AlPO_4 and K_5P_3O_(10))compounds during 400 ℃-800 ℃,which own obvious adhesive phenomenon and porous structure with the apparent porosity of 58.4%.Further reactions between phosphates other than reactions among Al_2O_3·2SiO_2 and α-SiO_2 can generate KAlP_2O_7 at 1 000 ℃ and the density of residualproduct is improved by low melting point phosphate filling pore to form relatively dense structure and decrease the apparent porosity to 44.4%.The flame resistant and self-supported ceramic materials are expected to enhance the fire-retarding synergistic effect between APP and muscovite.胡盛 CHEN Fei LI Junguo 沈强 ZHANG Lianmeng 2016Journal of Wuhan University of Technology(Materials Science)2016,31,2:3
17Blue revolution for food security under carbon neutrality: A case from the water-saving and drought-resistance rice显示文摘The increasing concentration of greenhouse gases(GHGs)in Earth's atmosphere leads to global warming,which further causes a series of climate changes and does great harm to both human society and natural ecosystems.Agricultural GHG emissions,mainly in theform of methane(CH4)and nitrous oxide(N2O),areasignificantsourceofGHGs,accountingfor~14%total global GHGs(Zhang et al.,2022).One major source of agricultural GHGs is CH4 emissions from rice paddies,which is responsiblefor~10%-12%ofhuman-inducedCH4emissions(van Groenigen et al.,2013)and contributes~2.40%to the enhanced global warming effect(Zhang et al.,2022).The global warming potential of GHGs emissions from rice systems is roughly four times higher than either wheat or maize(Linquist et al.,2012).Hui Xia Xianxian Zhang Yi Liu Junguo Bi Xiaosong Ma Anning Zhang Hongyan Liu Liang Chen Sheng Zhou Huan Gao Kai Xu Haibin Wei Guolan Liu Feiming Wang Hongyang Zhao Xingxing Luo Danping Hou Qiaojun Lou Fangjun Feng Liguo Zhou Shoujun Chen Ming Yan Tianfei Li Mingshou Li LeiWang Zaochang Liu Xinqiao Yu HanweiMei Lijun Luo 2022Molecular Plant2022,15,9:3
18Improved VGG Model for Road Traffic Sign Recognition显示文摘Road traffic sign recognition is an important task in intelligent transportation system.Convolutional neural networks(CNNs)have achieved a breakthrough in computer vision tasks and made great success in traffic sign classification.In this paper,it presents a road traffic sign recognition algorithm based on a convolutional neural network.In natural scenes,traffic signs are disturbed by factors such as illumination,occlusion,missing and deformation,and the accuracy of recognition decreases,this paper proposes a model called Improved VGG(IVGG)inspired by VGG model.The IVGG model includes 9 layers,compared with the original VGG model,it is added max-pooling operation and dropout operation after multiple convolutional layers,to catch the main features and save the training time.The paper proposes the method which adds dropout and Batch Normalization(BN)operations after each fully-connected layer,to further accelerate the model convergence,and then it can get better classification effect.It uses the German Traffic Sign Recognition Benchmark(GTSRB)dataset in the experiment.The IVGG model enhances the recognition rate of traffic signs and robustness by using the data augmentation and transfer learning,and the spent time is also reduced greatly.Shuren Zhou Wenlong Liang Junguo Li Jeong-Uk Kim 2018Computers, Materials & Continua2018,,10:2
19Geochemical Characteristics of Wuyang Siliceous Rocks in the Southern Margin of North China Craton and its Constraint on the Formation Environment of BIF of Tieshanmiao Formation显示文摘Precambrian banded iron formation(BIF)is one of the most important mineral resources in China,mostly abundant in the North China Craton(NCC)with relatively less common in South China.Since the BIF and siliceous rocks both originated from chemical deposition,the syngenetic BIF and Siliceous rocks can help evaluate their environment of formation.We examine here the mineralogy and geochemistry of siliceous rocks associated with the Tieshanmiao Formation BIF,aiming to decipher the conditions of formation of both BIF and Siliceous rocks in the Wuyang area in the NCC.Analysis of the geochemical characteristics of whole rock shows that the Si O2 content of the siliceous rock ranges from 90.11%to 94.85%and is relatively high overall.Trace element contents of Ba and U are also high,the Ba/Sr ratio ranges from 3.89 to 25.28 and the U/Th ratio ranges from 0.09 to 0.20.Finally,theΣREE value of rare earth elements ranges from 57.03 ppm to 152.59 ppm,and these indexes all indicate that siliceous rock resulted from hydrothermal deposition.Plots of Al2 O3-Si O2,Si O2/(K2 O+Na2 O)-Mn O2/Ti O2 and Mn-10×(Cu+Co+Ni)-Fe in discrimination diagrams also verify this interpretation.However,both the Mg O content,ranging from 0.16 to 0.32,and the Fe/Ti ratio,ranging from 2.50 to 9.72,suggest that terrigenous material was added during the depositional process.Major and trace element parameters of siliceous rock,such as the Al/(A1+Fe+Mn)ratio(from 0.81 to 0.93),Mn O/Ti O2(from 0.00 to 0.17),Al/(Al+Fe)(from 0.82 to 0.93),Sc/Th ratio(from 0.21 to 0.50),U/Th(from 0.09 to 0.20),(La/Yb)N(from 0.83 to 3.04),and the(La/Ce)N(from 0.01 to 0.02)all imply that the siliceous rock formed in a continental margin.In addition,the Sr/Ba ratio from 0.08 to 0.26,theδCe value from 0.31 to 0.90,and theδEu value from 0.14 to 0.58,all indicate that the siliceous rock was formed at a relatively deeper water depth and under weak hydrodynamic conditions.Siliceous rock and BIF formed in the same geological setting,with the Si O2/(K2 O+Na2 O)ratio of siliceous rock ranging from 28.61 to 47.43,the Si O2/Al2 O3 ratio from 16.53 to 32.37,and the Si O2/Mg O ratio from 287.28 to 592.81,which are all in agreement with chemical deposition associated with volcanic eruptions.The Al2 O3/Ti O2 ratio from 37.82 to 50.30 indicates that the magma source of siliceous rock was of slightly intermediate composition.During the Late Archean in the Wuyang area,the high concentration and high purity Si O2 quickly precipitated from hydrothermal fluids to finally result in the accumulation of siliceous rock in a marginal sea,while the input corresponding to iron formation components was deposited to form iron formation layers,and limestone was only the product formed during the deposition intervals of siliceous rock and iron formations.In this study,the synsedimentary siliceous rocks of BIF act as a new way to provide direct evidence to understand the formation environment of BIF due to its high geochemical stability.LI Hongzhong HE Junguo LIANG Jin YANG Fei ZHAI Mingguo ZHANG Lianchang Voudouris PANAGIOTIS 2019Acta Geologica Sinica(English Edition)2019,93,6:2
20Preparation and surface modification of magnetic poly(methyl methacrylate) microspheres显示文摘A novel method for preparation of magnetic polymer microspheres by spraying suspension polymerization (SSP) was developed. Relatively uniform magnetic poly(methyl methacrylate) microspheres were prepared by the spraying suspension polymerization (SSP) using methyl methacrylate (MMA) as monomer, divinylbenzene (DVB) as cross-linking agent, benzoyl peroxide (BPO) as initiator and polyvinyl alcohol (PVA) as stabilizer in the presence of hydrophobic Fe3O4 magnetic fluid. The microspheres prepared were modified by surface chemical reaction. The magnetic properties and morphology of the microspheres were examined by SEM and VSM respectively. The active functional groups of microspheres were examined by infrared spectra. The results showed that microspheres with saturation magnetization of 16.8 emu/g showed distinct superparamagnetic characteristics and the magnetic microspheres with a size of 10 μm were relatively uniform.YANG Chengli GUAN Yueping XING Jianmin LIU Junguo AN Zhentao LIU Huizhou 2004Science China Chemistry2004,47,4:2
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