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Bearing Fault Diagnosis Based on Deep Discriminative Adversarial Domain Adaptation Neural Networks
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作者 Jinxi Guo Kai Chen +5 位作者 Jiehui Liu Yuhao Ma Jie Wu Yaochun Wu Xiaofeng Xue Jianshen Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2619-2640,共22页
Intelligent diagnosis driven by big data for mechanical fault is an important means to ensure the safe operation ofequipment. In these methods, deep learning-based machinery fault diagnosis approaches have received in... Intelligent diagnosis driven by big data for mechanical fault is an important means to ensure the safe operation ofequipment. In these methods, deep learning-based machinery fault diagnosis approaches have received increasingattention and achieved some results. It might lead to insufficient performance for using transfer learning alone andcause misclassification of target samples for domain bias when building deep models to learn domain-invariantfeatures. To address the above problems, a deep discriminative adversarial domain adaptation neural networkfor the bearing fault diagnosis model is proposed (DDADAN). In this method, the raw vibration data are firstlyconverted into frequency domain data by Fast Fourier Transform, and an improved deep convolutional neuralnetwork with wide first-layer kernels is used as a feature extractor to extract deep fault features. Then, domaininvariant features are learned from the fault data with correlation alignment-based domain adversarial training.Furthermore, to enhance the discriminative property of features, discriminative feature learning is embeddedinto this network to make the features compact, as well as separable between classes within the class. Finally, theperformance and anti-noise capability of the proposedmethod are evaluated using two sets of bearing fault datasets.The results demonstrate that the proposed method is capable of handling domain offset caused by differentworkingconditions and maintaining more than 97.53% accuracy on various transfer tasks. Furthermore, the proposedmethod can achieve high diagnostic accuracy under varying noise levels. 展开更多
关键词 Fault diagnosis transfer learning domain adaptation discriminative feature learning correlation alignment
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Optimal Design of Street-side Green Spaces: A Case Study of Tiaoshan Cultural Park in Yuncheng City, Shanxi Province 被引量:1
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作者 CHENG Zhaoxia LI Guangyao 《Journal of Landscape Research》 2014年第6期46-48,共3页
Street-side green spaces are located by urban roads, serving neighboring residents and business population, they are public spaces for citizens working, relaxing and communicating with each other. Landscape design of ... Street-side green spaces are located by urban roads, serving neighboring residents and business population, they are public spaces for citizens working, relaxing and communicating with each other. Landscape design of street-side green spaces is the manifestation of city culture, history and development. Through investigating actual conditions, cultural and historical context, and neighboring traffic of Tiaoshan Cultural Park, this study summarizes deficiencies of the original plant and landscape setting designs, and proposes optimal designs of the park according to the design principles of street-side green spaces. 展开更多
关键词 Landscape design Street-side green spaces Optimal design
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Biodiversity and Screening of Moderately Halophilic Bacteria with Hydrolytic and Antimicrobial Activities from Yuncheng Salt Lake,China
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作者 LI Xin YU Huiying 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期84-85,共2页
1 Introduction Yuncheng Salt Lake is an old lake with a history of more than 5000 years,which locates in the margins of the central plains of China,with an area of about 130 km.It was an important resource of salt for... 1 Introduction Yuncheng Salt Lake is an old lake with a history of more than 5000 years,which locates in the margins of the central plains of China,with an area of about 130 km.It was an important resource of salt for human consumption from early times.Major chemicals in Yuncheng Salt Lake contain Na Cl,Na2SO4 and Mg SO4(Gao et al.2007).In recent years,some halophilic bacteria and archaea were 展开更多
关键词 Biodi versity moderately halophilic bacteria Hydrol yses anti micr obial activity
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Bayesian inference of the crust–core transition density via the neutron-star radius and neutron-skin thickness data 被引量:2
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作者 Wen-Jie Xie Zi-Wei Ma Jun-Hua Guo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第6期125-133,共9页
In this work,we perform a Bayesian inference of the crust-core transition density ρ_(t) of neutron stars based on the neutron-star radius and neutron-skin thickness data using a thermodynamical method.Uniform and Gau... In this work,we perform a Bayesian inference of the crust-core transition density ρ_(t) of neutron stars based on the neutron-star radius and neutron-skin thickness data using a thermodynamical method.Uniform and Gaussian distributions for the ρ_(t) prior were adopted in the Bayesian approach.It has a larger probability of having values higher than 0.1 fm^(−3) for ρ_(t) as the uniform prior and neutron-star radius data were used.This was found to be controlled by the curvature K_(sym) of the nuclear symmetry energy.This phenomenon did not occur if K_(sym) was not extremely negative,namely,K_(sym)>−200 MeV.The value ofρ_(t) obtained was 0.075_(−0.01)^(+0.005) fm^(−3) at a confidence level of 68%when both the neutron-star radius and neutron-skin thickness data were considered.Strong anti-correlations were observed between ρ_(t),slope L,and curvature of the nuclear symmetry energy.The dependence of the three L-K_(sym) correlations predicted in the literature on crust-core density and pressure was quantitatively investigated.The most probable value of 0.08 fm^(−3) for ρ_(t) was obtained from the L-K_(sym) relationship proposed by Holt et al.while larger values were preferred for the other two relationships. 展开更多
关键词 Crust–core transition density of neutron stars Neutron-star radius Neutron-skin thickness Bayesian inference approach L–K_(sym)
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Trajectory equation of a lump before and after collision with other waves for generalized Hirota–Satsuma–Ito equation
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作者 夏亚荣 张开开 +1 位作者 姚若侠 申亚丽 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期163-171,共9页
Based on the Hirota bilinear and long wave limit methods,the hybrid solutions of m-lump with n-soliton and nbreather wave for generalized Hirota–Satsuma–Ito(GHSI)equation are constructed.Then,by approximating soluti... Based on the Hirota bilinear and long wave limit methods,the hybrid solutions of m-lump with n-soliton and nbreather wave for generalized Hirota–Satsuma–Ito(GHSI)equation are constructed.Then,by approximating solutions of the GHSI equation along some parallel orbits at infinity,the trajectory equation of a lump wave before and after collisions with n-soliton and n-breather wave are studied,and the expressions of phase shift for lump wave before and after collisions are given.Furthermore,it is revealed that collisions between the lump wave and other waves are elastic,the corresponding collision diagrams are used to further explain. 展开更多
关键词 Hirota bilinear method long wave limit hybrid solutions trajectory equation
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Saline soil enzyme activities of four plant communities in Sangong River basin of Xinjiang,China 被引量:11
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作者 ZhengJun GUAN Qian LUO +4 位作者 Xi CHEN XianWei FENG ZhiXi TANG Wei WEI YuanRun ZHENG 《Journal of Arid Land》 SCIE CSCD 2014年第2期164-173,共10页
Soil enzyme activity plays an important role in the conversion of soil organic carbon into inorganic carbon, which is significant for the global carbon cycle. In this study, we investigated the soil enzyme activities ... Soil enzyme activity plays an important role in the conversion of soil organic carbon into inorganic carbon, which is significant for the global carbon cycle. In this study, we investigated the soil enzyme activities of two ligninolytic enzymes (peroxidase and polyphenol oxidase) and five non-ligninolytic enzymes (a-l,4-glucosidase (AG); 13-1,4-gluco- sidase (BG); N-acetyl-[3-glucosaminidase (NAG); ~3-D-cellobiosidase (CBH); and ^-xylosidase (BXYL)) in four plant communities of the Sangong River basin in Fukang, North Xinjiang, China. The four typical plant communities were dominated by Haloxylon ammodendron, Reaumuria soongonica, Salsola passerina, and Tamarix rarmosissima, respec- tively, with saline soils of varied alkalinity. The results showed that the soil peroxidase activity decreased seasonally. The activities of the five non-ligninolytic enzymes decreased with increasing soil depths, while those of the two ligninolytic enzymes did not show such a trend. In the four plant communities, BG had the highest activity among the five non-ligninolytic enzymes, and the activities of the two ligninolytic enzymes were higher than those of the four non-ligninolytic ones (AG, NAG, CBH, and BXYL). The community of H. ammodendron displayed the highest activity with respect to the two ligninolytic enzymes in most cases, but no significant differences were found among the four plant communities. The geometric mean of soil enzyme activities of the four plant communities was validated through an inde- pendently performed principal component analysis (PCA), which indicated that different plant communities had different soil enzyme activities. The correlation analysis showed that soil polyphenol oxidase activity was significantly positively correlated with the activities of the five non-ligninolytic enzymes. The soil pH value was positively correlated with the ac- tivities of all soil enzymes except peroxidase. Soil microbial carbon content also showed a significant positive correlation (P〈0.01) with the activities of all soil enzymes except polyphenol oxidase. The results suggested that the H. ammoden- dron community has the highest ability to utilize soil organic carbon, and glucoside could be the most extensively utilized non-ligninolytic carbon source in the saline soil of arid areas in Xinjiang. 展开更多
关键词 soil enzyme activity saline soil Haloxylon ammodendron Reaumuria soongonica Salsola passerina Tamafix rarmosissima
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Carbon dioxide reforming of methane over Ni/Mo/SBA-15-La_2O_3 catalyst:Its characterization and catalytic performance 被引量:8
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作者 Jian Huang Renxiong Ma +2 位作者 Tao Huang Anrong Zhang Wei Huang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第5期465-470,共6页
关键词 CO2-reforming SBA-15 molecular sieve carbon deposition La-promoted
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Natural resource dependence, public education investment,and human capital accumulation 被引量:4
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作者 Hua-Ping Sun Wei-Feng Sun +1 位作者 Yong Geng Yu-Sheng Kong 《Petroleum Science》 SCIE CAS CSCD 2018年第3期657-665,共9页
This paper examines the relationships between natural resource dependence, public education investment, and human capital accumulation. It addresses why the “blessing” of abundant natural resources often turns into... This paper examines the relationships between natural resource dependence, public education investment, and human capital accumulation. It addresses why the “blessing” of abundant natural resources often turns into a “curse” in many countries and regions, focusing on the crowding-out effect of natural resources on human capital. According to our empirical analysis of provincial panel data from China, natural resource dependence is significantly and negatively correlated with human capital accumulation. The crowding-out effect of natural resources on human capital exists only in the central and western regions of China. Our introduction of an interaction term for natural resource dependence and public education investment underscores the possibility of investing in public education to reduce the crowding-out effect of natural resource dependence on human capital. The government should utilize the income of the natural resource sector to increase investment in education to enhance local human capital. 展开更多
关键词 Natural resource dependence Public education investment Human capital accumulation Resource curse
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Probing the density dependence of the symmetry energy with central heavy ion collisions 被引量:4
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作者 XIE Wenjie ZHANG Fengshou 《Nuclear Science and Techniques》 SCIE CAS CSCD 2013年第5期7-12,共6页
An improved isospin dependent Boltzmann Langevin model,in which the inelastic channels and momentum dependent interactions are incorporated,is used to investigate the high-density behavior of nuclear symmetry energy.B... An improved isospin dependent Boltzmann Langevin model,in which the inelastic channels and momentum dependent interactions are incorporated,is used to investigate the high-density behavior of nuclear symmetry energy.By taking several forms of nuclear symmetry energy,we calculate the time evolutions of neutron over proton ratio,π multiplicity and π-/π+ ratio,and the kinetic energy and transverse momentum spectra of π-/π+ ratio in the heavy ion collisions at 400A MeV.It is found that the neutron over proton ratio and π-/π+ ratio are very sensitive to the nuclear symmetry energy,and the π-is more sensitive to the nuclear symmetry energy than the π+.A supersoft symmetry energy results in a larger π-/π+ ratio. 展开更多
关键词 重离子碰撞 对称能 BOLTZMANN 中央 密度 探测 同位旋相关 相互作用
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Electrochemical Synthesis and Magnetic Studies of Ni-Fe-Co-Mn-Bi-Tm High Entropy Alloy Film 被引量:5
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作者 YAO Chen-zhong ZHANG Peng +2 位作者 TONG Ye-xiang XIA Dao-cheng MA Hui-xuan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第4期640-644,共5页
Amorphous Ni-Fe-Co-Mn-Bi-Tm high entropy alloy films were firstly prepared by potentiostatic electro- deposition. The results indicate that the six elements can be co-deposited in an organic system of DMF (N,N-dimeth... Amorphous Ni-Fe-Co-Mn-Bi-Tm high entropy alloy films were firstly prepared by potentiostatic electro- deposition. The results indicate that the six elements can be co-deposited in an organic system of DMF (N,N-dimethylformamide)-CH3CN. The surface of the film is composed of compact and uniform particles with triangular cone shape and a particle size of 100-200 nm. A simple face-centered-cubic structure is identified by XRD patterns after the films were annealed under Ar atmosphere. The annealed alloy film shows soft magnetic properties and the magnetization decreases with Fe content decreasing. 展开更多
关键词 High entropy alloy ELECTRODEPOSITION Magnetic property Heat treatment
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Effects of Ag layers on the microstructure and magnetic properties of CoPt/BN multilayer films 被引量:2
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作者 Lu Baohua WANG Fang 《Rare Metals》 SCIE EI CAS CSCD 2011年第2期137-141,共5页
Ag/[BN/CoPt]5/Ag and [BN/Ag/CoPt]5/Ag thin films were deposited on glass substrates by magnetron sputtering and then annealed in vac- uum at 600 ℃ for 30 min. The structures and magnetic properties of CoPt/BN multila... Ag/[BN/CoPt]5/Ag and [BN/Ag/CoPt]5/Ag thin films were deposited on glass substrates by magnetron sputtering and then annealed in vac- uum at 600 ℃ for 30 min. The structures and magnetic properties of CoPt/BN multilayer films were investigated as a function of Ag layer thickness. It was found that the face-centered tetragonal (fct) (001) texture of CoPt was improved greatly by introducing the Ag toplayer or sublayer together with an Ag underlayer. Good (001)-oriented growth, low intergrain interactions as well as high perpendicular anisotropy can be obtained in the Ag(3 nm)/[BN(2.5 nm)/CoPt(3 nm)]5/Ag(7 nm) and [BN(2.5 nm)/Ag(2 nm)/CoPt(3 nm)]5/Ag(10 nm) films, which become potential candidates for ultrahigh density magnetic recording media. 展开更多
关键词 magnetic thin films MULTILAYERS magnetic recording magnetron sputtering silver MICROSTRUCTURE magnetic properties
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Incoherently Coupled Grey-Grey Spatial Soliton Pairs in Biased Two-Photon Photovoltaic Photorefractive Crystals 被引量:1
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作者 苏艳丽 姜其畅 吉选芒 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第5期943-946,共4页
无条理地联合了灰灰色的屏幕光电的空间 soliton 对在不变的条件下面在偏导的二光子的光电的 photorefractive 晶体被预言。如果事件横梁有一样的极化,这些灰灰色的屏幕光电的 soliton 对能被建立,波长,并且是互相支离破碎的。灰灰... 无条理地联合了灰灰色的屏幕光电的空间 soliton 对在不变的条件下面在偏导的二光子的光电的 photorefractive 晶体被预言。如果事件横梁有一样的极化,这些灰灰色的屏幕光电的 soliton 对能被建立,波长,并且是互相支离破碎的。灰灰色的屏幕光电的 soliton 对能被看作灰灰色的屏蔽 soliton 对和开或靠近电路的灰灰色的光电的 soliton 对的统一形式。 展开更多
关键词 光子晶体 相干耦合 孤子对 色空间 光折变 灰色 光伏 偏置
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Humulus japonicus extract alleviates oxidative stress and apoptosis in 6-hydroxydopamine-induced PC12 cells 被引量:2
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作者 Feng Wang Byoung Ok Cho +2 位作者 Jae Young Shin Suping Hao Seon Il Jang 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2022年第5期197-206,共10页
Objective:To explore the possible neuroprotective activities of Humulus japonicus extract against Parkinson's disease(PD)in a cellular model.Methods:PD was modeled in PC12 cells using 6-hydroxydopamine(6-OHDA).The... Objective:To explore the possible neuroprotective activities of Humulus japonicus extract against Parkinson's disease(PD)in a cellular model.Methods:PD was modeled in PC12 cells using 6-hydroxydopamine(6-OHDA).The cell activity,intracellular levels of reactive oxygen species(ROS),anti-oxidative and anti-apoptotic effects,and other related indicators and related signaling pathways were evaluated to elucidate the neuroprotective effects of Humulus japonicus extract.Results:Humulus japonicus extract exhibited anti-oxidative and anti-apoptotic effects in 6-OHDA-stimulated PC12 cells.It also reduced oxidative stress-induced ROS accumulation;upregulated antioxidant enzymes,such as glutathione,catalase,heme oxidase-1,and 8-oxguanine glycosylase 1;promoted cell survival by decreasing BAX and increasing Bcl-2 and sirtuin 1 expression via the MAPK and/or Nrf2 signaling pathways.Conclusions:Humulus japonicus extract has antioxidative and anti-apoptotic effects and could be developed as a promising candidate for preventing and treating oxidative stress-related neurodegenerative diseases. 展开更多
关键词 Humulus japonicus Parkinson’s disease Oxidative stress APOPTOSIS MAPK PC12 cells Nrf2
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Effect of NaCl Stress on Seedling Growth of Sunflower 被引量:1
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作者 Zan Yaling Wei Shuzhen 《Plant Diseases and Pests》 CAS 2016年第1期32-35,共4页
[ Objective ] The paper was to study effects of different salt treatments on growth and physiological activity of sunflower seedlings, in order to provide a theoretical basis for sunflower cultivation in saline soil. ... [ Objective ] The paper was to study effects of different salt treatments on growth and physiological activity of sunflower seedlings, in order to provide a theoretical basis for sunflower cultivation in saline soil. [Method] With 567DW sunflower as the material, effects of different concentrations of NaC1 (0, 0.06, 0. 12, 0. 18, 0.24 mol/L) on growth and physiological activity of sunflower seedlings were studied. [ Result] With the increasing concentration of NaCl, the morphological indexes of sunflower decreased significantly; MDA content increased, while Pro content and POD activity first increased and then decreased. Under the treatment of 0. 12 mol/L, Pro content and POD activity reached the maximum value, respectively. [ Conclusion] The critical salt-tolerance concentration of sunflower was about 0.12 mol/L. 展开更多
关键词 SUNFLOWER NaCl stress Malondialdehyde (MDA) Proline (Pro) Peroxidase (POD)
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Physiological Characteristics of Boscalid Against Botrytis cinerea from Strawberry 被引量:1
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作者 Li Pei-qian Feng Bao-zhen Sun Nu-nu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2019年第4期23-30,共8页
A total of 96 monoconidial Botrytis cinerea strains were isolated from strawberry field.Physiological characteristics and resistance analysis to boscalid were investigated.Most isolates showed resistant phenotype and ... A total of 96 monoconidial Botrytis cinerea strains were isolated from strawberry field.Physiological characteristics and resistance analysis to boscalid were investigated.Most isolates showed resistant phenotype and the resistance frequency of highly resistant isolates was as high as 45.10%.The effective concentration that inhibited conidia germination by 50% relative to the control values for sensitive isolates ranged from 0.068 to 60.56μg·mL^-1 in conidia germination assays.Compared to the sensitive strains,the boscalid-resistant strains had a significant increase in phenylalanine ammonia lyase(PAL)and peroxidase(POD)activity and more sensitivity to boscalid pressure.Fitness analysis showed statistically significant difference between sensitive and resistance isolates.Sequencing of SdhB gene indicated that a single mutation corresponded to His272.The results suggested that resistance to boscalid in B.cinerea populations could result in failure to control gray mold.These results would enrich the understanding of the resistance mechanism of B.cinerea to boscalid. 展开更多
关键词 Botrytis cinerea BOSCALID RESISTANCE
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Characterization, Adsorption Properties and Mechanism of Modified Sophora Japonica Leaves to Benzene 被引量:1
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作者 陈莉 李新 +1 位作者 张爱平 姜俊霞 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第9期1474-1484,共11页
The biosorbent has been prepared with the sophora japonica leaves from the agricultural residue as the raw material by the alkaline blanching method, and characterized by BET, SEM, EDS and FTIR analysis methods. The m... The biosorbent has been prepared with the sophora japonica leaves from the agricultural residue as the raw material by the alkaline blanching method, and characterized by BET, SEM, EDS and FTIR analysis methods. The modified sophora japonica leaves possessed more adsorption sites and had more strongly adsorbed chemical groups, which were beneficial to the adsorption. We have further investigated the adsorption performance of the indoor benzene. The secondary regression orthogonal rotation was employed to optimize the preparation process for the optimal processing conditions and regression model. The effects of single factors such as particle size, temperature, and adsorbent dosage of the sophora japonica leaves were analyzed, and adsorption isotherms and adsorption kinetics were studied. The results show that the optimal adsorption conditions were as follows: sodium hydroxide concentration with 0.1 mol/L, water bath time for 70 min, water bath temperature at 60 ℃ and Ymax = 21.38%. The best single factors included particle size with 30 mesh, temperature at 25 oC, 3 g dosage, which are consistent with the Freundlich model, and the adsorption state was more inclined to multilayer active site adsorption with 25 mg/g of saturated adsorption amount;furthermore, the adsorption kinetics followed the quasi-secondary kinetic model(R2 = 0.9731) and the adsorption process was a physicochemical mixed adsorption process controlled by chemisorption;Compared with the adsorption effect, the removal rate to the benzene of modified sophora japonica leaves was significantly superior to other materials at the level 1%, namely, modified sophora japonica leaves > diatomite> bamboo charcoal > activated carbon > macroporous resin, and the modified biosorbent had a good cycle regeneration ability. 展开更多
关键词 SOPHORA JAPONICA LEAVES BENZENE structure CHARACTERIZATION ADSORPTION property
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Preparation of Copper Phthalocyanine Crystals Using Solvothermal Synthesis 被引量:2
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作者 XIA Dao-cheng LI Wan-cheng +8 位作者 WANG Xu YU Shu-kun FAN Cui-xiang MA Chun-yu CHENG Chuan-hui FAN Zhao-qi DU Guo-tong CONG Fang-di DU Xi-guang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第4期407-410,共4页
A novel solvothermal synthesis method for the direct growth of B-form crystals of copper phthalocyanine(CuPc) is presented in this article. With quinoline as solvent, crystals were grown after cooling the reaction m... A novel solvothermal synthesis method for the direct growth of B-form crystals of copper phthalocyanine(CuPc) is presented in this article. With quinoline as solvent, crystals were grown after cooling the reaction mixture of 1,3-diiminoisoindoline and copper oxide, heated for 9 h at 270 ℃, to room temperature in an autoclave. These high quality crystals were suitable for characterization measurements. The single-crystal diffraction data show a monoclinic system unit cell: a=1.4668(3) nm, b=0.48109(10) nm, c=1.9515(7) nm, a=90°, B=121.04(2)°, r=90°, where the corresponding cell volume is 1.17991 nm^3. Needle-like single crystals of CuPc up to 10.5 mm in length were obtained. The influences of different temperatures, reaction time and solvent volume on the crystal yields were also discussed. Optimum reaction conditions were 10 mL of quinoline, at 270 ℃ for 8 h. 展开更多
关键词 Solvothermal synthesis Single crystal CUPC QUINOLINE SOLVENT AUTOCLAVE
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Two Coordination Novel Polymers Based on a Flexible Ligand N,N'-diacetic Acid Imidazolium 被引量:2
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作者 柴小川 高晓娜 +2 位作者 李晖 张汉辉 韩秋萍 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第3期463-470,共8页
{[Cu_3(cis-DAM)_4(OH)_2]·12H_2O}_n 1 and [Ag_3(trans-DAM)_2(NO_3)]_n 2 with a flexible ligand N,NA-diacetic acid imidazolium(HDAM) were synthesized and characterized by single-crystal X-ray diffraction.... {[Cu_3(cis-DAM)_4(OH)_2]·12H_2O}_n 1 and [Ag_3(trans-DAM)_2(NO_3)]_n 2 with a flexible ligand N,NA-diacetic acid imidazolium(HDAM) were synthesized and characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the orthorhombic I222 space group with a = 12.033(2),b = 12.498(3),c = 14.963(3) A,V = 2250.4(8) A^3,Z = 8,C_7H_(13.5)N_2O_(7.5)Cu_(0.75),M_r = 293.35,D_c = 1.732 g·cm^-3,F(000) = 1210,GOF = 1.087,the final R(I 〉 2σ(I)) = 0.0521 and w R(all data) = 0.1386. Compound 2 crystallizes in the monoclinic C2/c space group with a = 21.601(4),b = 8.321(2),c = 13.589(3) A,β = 126.95(3)°,V = 1951.9(7) A^3,Z = 8,C_7H_7N_(2.5)O_(5.5)Ag_(1.5),M_r = 375.96,D_c = 2.559 g·cm^-3,F(000) = 1448,GOF = 1.017,R(I 〉 2σ(I)) = 0.0222 and w R(all data) = 0.0633. Compound 1 displays a novel 2D layer,consisting of a couple of left-helical chains with a pitch of 12.498(3) A formed by μ_3-cis-DAM~– ligands and Cu(1) ions,which are stabilized by hydrogen bonding interactions to give a 3D supramolecular framework. As for 2,Ag(1) ions are doubly bridged by trans-DAM~– and NO_3~– to form [Ag(1)_2O_4] chains,which are further connected by Ag(2) and trans-DAM~– to build a 3D framework. Additionally,thermogravimetric analyses,FT-IR spectroscopy,UV-visible spectroscopy,and the fluorescent properties were discussed. 展开更多
关键词 N N'-diacetic acid imidazolium crystal structure helical chains fluorescent
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Investigation on the Association of Soil Microbial Populations with Ecological and Environmental Factors in the Pearl River Estuary 被引量:1
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作者 Yanchun Qiao Donglin Xu +5 位作者 Hongjuan Yuan Bei Wu Bishao Chen Yaowen Tan Jianrong Lin Dongliang Guo 《Journal of Geoscience and Environment Protection》 2018年第3期8-14,共7页
An investigation on the soil microbe populations from an agricultural inning area at the Pearl River estuary in Guangdong province, China was conducted via high through-put sequencing. The results revealed abundant di... An investigation on the soil microbe populations from an agricultural inning area at the Pearl River estuary in Guangdong province, China was conducted via high through-put sequencing. The results revealed abundant diversity in the soil bacterial and fungal populations. In total, 197103 sequence tags were obtained from soil samples, most of which represented bacterial genera Actinomycetes, Bacillus and Marinobacter, while a majority of 118378 tags obtained were derived from fungal genera Clostridium, Devosia, Bradyrhizobium, Bdellovibrio, Phenylobacterium, Penicillium, and Emericella. Furthermore, nine physiological indexes (pH, available phosphorous, basic-group nitrogen, available potassium, catalase, sucrose, urease, phosphatase, and organic matters) were measured in three soil samples, and the association between these physiological indexes and microbe population composition was examined. The results revealed obvious inter-sample differences associated with ten dominating microbial groups: genera Clostridium, Devosia, Bradyrhizobium, Bdellovibrio, Phenylobacterium, and Penicillium were mainly impacted by pH (with a positive correlation), genera Sphingomonas and Acinetobacter mainly by available phosphorous (positive correlation), and genera Gemmatimonas and Pseudomonas by both pH and available phosphorous (negative correlation). Our study suggested that regulation of microbial species/populations might help improve soil environment to facilitate the growth of crops’ above-ground parts, and this provides practical information for inning agriculture. 展开更多
关键词 High Through-Put Analysis PEARL River ESTUARY Soil Microbial Population En-vironmental FACTORS ASSOCIATION
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Temporal Behavior of Low-Amplitude Grey Spatial Solitons in Biased Two-Photon Photorefractive Crystals
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作者 姜其畅 苏艳丽 吉选芒 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第12期1097-1100,共4页
在低振幅的政体由于二光子的 photorefractive 效果屏蔽空间 solitons 的灰色的时间的性质被分析。结果显示宽广 solitons 在开始被产生,并且向稳定的状态 monotonically 作为时间发展灰 solitons 减少的紧张宽度到最小的价值。在一样... 在低振幅的政体由于二光子的 photorefractive 效果屏蔽空间 solitons 的灰色的时间的性质被分析。结果显示宽广 solitons 在开始被产生,并且向稳定的状态 monotonically 作为时间发展灰 solitons 减少的紧张宽度到最小的价值。在一样的繁殖时间, solitons 的 FWHM 与增加或 m 减少减少。而且, solitons 的形成时间是独立人士和 m。时间接近到绝缘的松驰时间决定的一个常数。 展开更多
关键词 空间孤子 光折变效应 时间行为 光子晶体 灰色 低振幅 时间属性 稳定状态
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