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The planting of the vegetation on the floodplain helps the ecological restoration, which is the main form of the river’s ecological corridor. Therefore, the current research of the river dynamics focuses on the water movement under a compound channel with the vegetated floodplains. Two simulated vegetation species are selected in this paper for the flume simulation experiments of the floodplain vegetation, and the compound channel is divided into three subregions in the transverse direction. The Navier-Stokes equation and the eddy viscosity theory are applied to obtain the transverse distribution of the depth-averaged velocity and the results agree well with the experimental data. This paper proposes a new method based on the analytical solution of the flow velocity distribution to calculate the average flow velocity in each section. Calculation results can effectively simulate the average flow velocity of the measured sections. The description of the pollutant transport processes in a moving stream requires a refined determination of the dispersion coefficients in the compound channel. The process of the pollutant concentrations in each zone and the reasons for their occurrence are elucidated on the basis of the experimental results. Simultaneously, the measured values of the longitudinal dispersion coefficients are obtained by the “routing procedure,” and a two-zone model of the pollutant dispersion is constructed on the basis of the hydrodynamic study. The prediction method for the longitudinal dispersion coefficients is also presented. Applying the predicted and measured section average flow velocities to the two-zone model to predict the longitudinal dispersion coefficient, and the average relative errors are only 4.17%, 7.15%, respectively. This result indicates that the two-zone model can effectively predict the longitudinal dispersion coefficients. The calculation methods for the longitudinal dispersion coefficients from—various studies are compared. The results reveal that the predicted values of these calculation methods are all larger than the measured values, indicating that the vegetation has a considerable influence on the dispersion process. This study comprehensively shows the dispersion features of the pollutants and provides a theoretical basis for the planning and the design of the vegetated ecological corridors.

Neonicotinoid insecticides (NNIs) are extensively utilized globally because of their efficient and broad-spectrum properties. However, their residues are also extensively distributed in the environment. Herein, MIL-101-SO3Na with abundant −NH– and sulfonate groups was synthesized via chloromethylation and nucleophilic substitution postmodification strategies and used to extract NNIs via solid-phase extraction. MIL-101-SO3Na was enhanced by introducing C–H···N hydrogen bonds to strengthen interaction forces and −SO3Na groups to adjust surface charge and enhance electrostatic attraction. This modification and the substantial specific surface area (998 m2·g–1) of the metal–organic framework markedly enhanced the enrichment efficiency of MIL-101. The proposed method based on MIL-101-SO3Na exhibited a minimal detection threshold (0.04–0.87 ng·L–1), an extensive linear spectrum (1–2000 ng·L–1), and notable accuracy (a variation of 3.02–11.8%) in water and drink samples. NNI concentrations between 0.25 and 24.2 ng·L–1in fruit juice and tea samples were accurately identified using the proposed method, demonstrating its feasibility in practical applications. The postmodification of MIL-101-SO3Na is an exceptional and promising approach for the sensitive detection of ultratrace NNI levels in complex matrices.

otrAresembles elongation factor G (EF-G) and is considered to be an oxytetracycline (OTC)-resistance determinant in Streptomyces rimosus. In order to determine whether otrAalso conferred resistance to OTC and other aminoglycosides to Streptomyces coelicolor, the otrAgene from S. rimosusM527 was cloned under the control of the strong ermE* promoter. The resulting plasmid, pIB139-otrA, was introduced into S. coelicolorM145 by intergeneric conjugation, yielding the recombinant strain S. coelicolorM145-OA. As expected S. coelicolorM145-OA exhibited higher resistance levels specifically to OTC and aminoglycosides gentamycin, hygromycin, streptomycin, and spectinomycin. However, unexpectedly, S. coelicolorM145-OA on solid medium showed an accelerated aerial mycelia formation, a precocious sporulation, and an enhanced actinorhodin (Act) production. Upon growth in 5-L fermentor, the amount of intra- and extracellular Act production was 6-fold and 2-fold higher, respectively, than that of the original strain. Consistently, reverse transcription polymerase chain reaction (RT-PCR) analysis revealed that the transcriptional level of pathway-specific regulatory gene actII-orf4was significantly enhanced in S. coelicolorM145-OA compared with in S. coelicolorM145.

We investigated the nanoscale thermal bubble nucleation based on the principle of Coulter counter. With micro-nanofabrication technologies, a device was designed and fabricated, and a detection platform was set up which was used to investigate the thermal bubble nucleation of aqueous solution confined in a nanochannel with a cross size of about 100 nm×100 nm. Results show that with the temperature of the solution confined in the nanochannel increasing, the current through the channel increases first and then decreases, and vanishes after a fluctuating period. It can be found that the generating thermal bubbles can hinder the current flowing through the nanochannel. In addition, the shrinking and expanding of thermal bubbles’ volume correspond to the increase and decrease of the current. Finally, the thermal bubbles block the nanochannel entirely. Through the experiment results, our device can be applied to investigate the complex behaviors of thermal bubble produced in aqueous solution confined in nanochannels, effectively.

The research on the mechanical properties and thermal stability of the natural rubber filled with different dosage of Zinc oxide (ZnO). The results showed that with the increase of the content of the ZnO, the tensile strength first increased, then decreased the, but the tear strength showed a trend of increase,the thermal stability had improved; When the amount of ZnO added was 9, damping performance was better.

Stable aqueous solution of purple carbon black (PCB) was prepared first and then added to prevulcanized natural rubber latex. The effects of the amount of PCB, silane coupling agent and the type of silane coupling agent on the mechanical properties of the vulcanized latex film were researched. The results show that the best mechanical properties were obtained when the vulcanized film was filled with 6 phr PCB modified by KH560. TG shows that thermal stability of the film with PCB modified by KH560 increased. DSC shows that the glass transition temperature of the film increased after adding PCB.

Waste rubber powder (WRP) is global concern, with the development of rubber industry. However, WRP with three-dimensional structure is insoluble and nonmelting and doesnt blend with raw rubber very well. Before added into raw rubber, WRP should be modified. In this paper ,the modification methods of WRP which contain grafting, sol-gel and reactive gas treatment method,through the unbroken three-dimensional network are described.

The silica/polyacylate composite latex was prepared via miniemulsion polymerization. Fluorinated acrylate monomer was used the co-stabilizer and hydrophobic modifier. The effect of fluorinated acrylate on stability of the composite latex was compared with the traditional co-stabilizer. The composite latex and the resultant film were characterized by Fourier transformation infrared spectroscopy, Dynamic laser scattering, Water contact angle. Fluorinated acrylate can stabilize the miniemulsion polymerization as the co-stabilizer and the resultant film has good durability of hydrophobicity under high moisture environments.

The characteristics of open CNC system and the current several open CNC system models are introduced in this paper. In order to overcome the contradiction between the frequent changes demand and the closure of the traditional system, the open CNC system software and hardware architectures were investigated based on web-collaborative design and development, which improve the system development efficiency. Using the Windows XP operating system as a software platform, the Visual C++ 6.0 object-oriented programming language is adopted to design the CNC drilling control software based on the "PC + NC" the model and modular co-design methods, which improve the openness of the CNC system.

AbstractThe thermooxidative degradation of natural rubber (NR) coagulated by microwave radiation (NR-m) was investigated by thermogravimetry (TG) analysis, and compared with NR coagulated by acid (NR-a). It was found that the degradation process is not a one-step reaction, the main degradation process occurs at 300–400ºC, and the equilibrium degradation temperatures of NR-m are higher than those of NR-a. Different methods were used to find the most probable kinetic model and the Arrhenius para­meters (activation energy Eand preexponential factor A) for the main stage of thermooxidative degradation of NR-m. The results show that the values of Eand A, obtained from the Coats-Redfern method, are highly variable with the kinetic model chosen and the heating rate (β), and the apparent activation energy (E0) when βapproaches zero for the Dntype kinetic model is in the range of 96.7–106.4 kJ ∙ mol-1. The mean values of E, calculated by the Friedman and Flynn-Wall-Ozawa (FWO) methods, are 113.8 and 83.3 kJ ∙ mol-1, respectively, suggesting Ein the range of 83.3–113.8 kJ ∙ mol-1. Comparison of these two ranges indicates the most probable kinetic model to be Dntype kinetic models, corresponding to a diffusion-controlled mechanism.

The modification methods of waste rubber powder(WRP) which contain mechanochemical, microwave, ultrasonic, devulcanization in supercritical material and microbial devulcanization method through cutting off three-dimensional network are described. More emphasis is put on devulcanization mechanism and the defects of each method as the devulcanization process is often accompanied with the main rubber chains degradation are also discussed. When modified WRP is added into rubber matrix, the mechanical properties of composite and compatibility between virgin rubber and WRP are improved. So the mode of core modification on WRP is built, through the broken three-dimensional network modification methods of WRP.

It was the first time to study the catalytic effect of mesoporous magnetic Fe3O4 nanoparticles on the biohydrogen production. The mixed culture used in this study just suffered from an alkaline shock and lost its bioactivity of hydrogen production. We use mesoporous Fe3O4 nanoparticles and ferrous ions as activators to recover the bioactivity of the mixed culture. The results indicate that the improvement of biohydrogen yield by mesoporous Fe3O4 was obvious larger than that by ferrous ions. The maximum yield of cumulative hydrogen production was obtained at the mesoporous Fe3O4 nanoparticles of 400 mg·L-1, which is 26% higher than that of the blank. The lag phases for hydrogen production in the tests added with mesoporous Fe3O4 nanoparticles were decreased to 12 h, which are 50 h less than those of the corresponding ferrous ions and blank tests.

An electroanalysis method of determining Chloramphenicol (CAP) based on the eletrocalysis property of DNA-hydroxyapatite modified electrode (dsDNA/HAp/GCE) was setted up. In KH2PO4-Na2HPO4 buffer solution with pH 6.0 cotaining 0.1 mol·L-1 KCl, the peak current was proportional to the concentration of CAP in the range of 2.80 × 10-7 to 3.60 × 10-6 mol·L-1, with a detection limit of 1.35 × 10-7 mol·L-1. The linear regress equation was ip (μA) = 5.865 + 0.4784 c (µmol·L-1), and the linear correlation coffcient was 0.9942. The method has been successfully applied to the quantitative analysis of CAP in real Chloramphenicol eye drops samples, which totally meet the demand of microanalysis. The relative standard deviation samples analysis results was 1ess than 3%.

Natural rubber latex (NRL) modified by holgonated addition with trichlorobromomethane was prepared. The thermal properties of modified NRL were analyzed by thermogravimetric analysis (TG/DTG),differential scanning calorimetry (DSC) and dynamic mechanical analysis(DMA). The results showed that the thermal stability of modified NRL was lower than NRL and the thermal degradation of modified NRL was two-stage decomposition. With increasing of stress frequency, loss modulus and storage modulus of latex increased,while loss modulus and storage modulus of modified latex decreased,compared with NRL.

As one of the most important parts of the financial organizations nowadays, banking industry plays an important role in not just the area of high-speed operation of the sociaty’s economy but also in the area of currency exchange. The Wave of Information Technology, which has caused a swift-development of the whole world’s economy, brings about both opportunity and challengs never arised to the banking industry. The sociaty, as it is becoming more intellectual and automatic, has post a harder demand for the working efficiency of the banking industry. Therefore, the banking industry must enhance its construction of informationization and automation in order to strengthern its competitiveness as well as the economic construction of service sociaty. Banking office automation will improve the working efficiency along with modernized management level in the light of advanced computer technology.

Fission-neutron radiation damage is hard to treat due to its critical injuries to hematopoietic and gastrointestinal systems, and so far few data are available on the therapeutic measures for neutron-radiation syndrome. This study was designed to test the effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) in dogs which had received 2.3 Gy mixed fission-neutron-γ irradiation with a high ratio of neutrons (~90%). Following irradiation, rhG-CSF treatment induced 100% survival versus 60% in controls. Only two of five rhG-CSF-treated dogs experienced leukopenia (white blood cells [WBC] count < 1.0 × 10(9)/L) and neutropenia (neutrophil [ANC] count < 0.5 × 10(9)/L), whereas all irradiated controls displayed a profound period of leukopenia and neutropenia. Furthermore, administration of rhG-CSF significantly delayed the onset of leukopenia and reduced the duration of leucopenia as compared with controls. In addition, individual dogs in the rhG-CSF-treated group exhibited evident differences in rhG-CSF responsiveness after neutron-irradiation. Finally, histopathological evaluation of the surviving dogs revealed that the incidence and severity of bone marrow, thymus and spleen damage decreased in rhG-CSF-treated dogs as compared with surviving controls. Thus, these results demonstrated that rhG-CSF administration enhanced recovery of myelopoiesis and survival after neutron-irradiation.

A series of 1,4-substituted phthalazine derivatives were designed and synthesized. All the prepared compounds were screened for their cytotoxic activities against A549, HT-29 and MDA-MB-231 cell lines in vitro. Among them, compounds 7a–7hshowed excellent selectivity for MDA-MB-231 cell line with IC50values from 1nmol/L to 0.92μmol/L. A preliminary SAR study of these derivatives was performed.

A novel series of 5H-pyridazino[4,5-b]indoles were designed and synthesized in order to find novel potent anticancer compounds. The structures were confirmed by 1H NMR and MS. Their antiproliferative activities against two cancer cell lines were tested by the MTT method in vitro. Three of compounds (1e, 1g, and 1h) exhibited potent antiproliferative activities, especially compound 1h (with IC50 values of 5.2μmol/L and 1.9μmol/L against Bel-7402 and HT-1080, respectively). The preliminary structure–activity relationships of 5H-pyridazino[4,5-b]indole derivatives were discussed.

ABSTRACTBackgroundCardiovascular diseases (CVDs) are the leading causes of death in China. Little is known about the CVD burden and risk factors in Henan Province, China.ObjectiveTo analyze the CVD burden and main risk factors between 1990 and 2017 in the Henan Province in China.MethodsThe methodological framework and analytical strategies adopted in the Global Burden of Disease Study 2017 were used.Results(1) Age-standardized mortality rate attributed to CVDs increased from 355.0 per 100,000 persons in 1990 to 364.1 per 100,000 persons in 2017 in Henan. (2) Age-standardized disability adjusted life years (DALYs) rate fell by 3.9% from 1990 to 2017. However, the number of DALYs attributed to CVDs increased by 75.9% from 4.2 million person-years in 1990 to 7.3 million person-years in 2017. (3) The age-standardized years lived with disability (YLDs) rate increased by 27.5% from 1990 to 2017. However, years of life lost (YLLs) rate decreased by 6.7% from 1990 to 2017. The contribution of YLLs to the DALYs decreased from 91.4% in 1990 to 89.2% in 2017. (4) Stroke (52.3%) and ischemic heart diseases (38.8%) accounted for 91.1% of total CVDs DALYs among adults in 2017. (5) Dietary factors such as high intake of sodium, alcohol use and low intake of fruits, high systolic blood pressure, and tobacco use were the top risk factors for CVDs, and the estimated population attributable fraction in 2017 was 69.4%, 56.7% and 25.2%, respectively.ConclusionsThe absolute burden of CVDs in Henan is still high, although age-standardized DALYs declined between 1990 and 2017. The prevention and control of stroke and ischemic heart diseases should focus on a few modifiable risk factors which mainly contributed to the burden of CVDs, such as dietary factors, high systolic blood pressure, and tobacco use.

A series of novel diaryl ureas containing 4-[(2-amino-6-trifluromethyl)pyrimidine-4-yl]piperazine-1-yl group were synthesized and evaluated for their cytotoxic activities in a panel of human cancer cell lines. Among them, compound 2pdemonstrated significant inhibitory activities against MDA-MB-231, HT-29 and MCF-7 cell lines with IC50values of 0.016, 0.63, 0.001μmol/L, respectively.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.