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We constructed two novel multifunctional copper complexes as efficient catalysts for the OER and photocatalytic degradation of azo dyes.

We constructed eight MOFs with semiconductor behavior, discussed their structures in detail, and explored their practical applications.

Electrocardiography can provide useful prognostic information in acute pulmonary embolism (APE). Several abnormal QRS changes in lead V1, including notched or fragmented QRS, incomplete or complete right bundle branch block (IRBBB or CRBBB) and the QR sign, which are associated with APE, are of prognostic significance. To illustrate this, we describe lead V1 QRS changes in combination with the clinical state of six APE patients. The dynamic ECG changes suggest that a change from a diminution of the S wave amplitude to notched S wave, next to RBBB and then to the QR sign indicate worsening of the patients' condition, and vice versa. Also, a diminution of the S wave amplitude in lead V1 associated with a final R' wave in the right precordial accessory leads indicates the possibility of hidden RBBB. Understanding dynamic QRS changes in APE may aid in risk stratification.

The appearance of the nitrogen-rich energetic MOFs provides another opportunity for the new-generation of high energetic explosives. In this work, an insensitive energetic nitrogen-rich ligand, 3-amino-1, 2, 4-triazole (Hatz) was imported into the system of transition-metal azides via the coordination polymerization strategy in the hope to prepare mixed-ligand nitrogen-rich high energetic MOF materials with low sensitivity and finally a solvent-free 3D energetic compacted metal-organic framework (MOF), Cd3(atz)4(N3)2 (1) was successfully isolated under hydrothermal conditions. Compound 1 was characterized by single crystal X-ray diffraction, IR spectroscopy, elemental analysis (EA), different scanning calorimetry (DSC), and thermogravimetry analysis (TGA). Topological analysis shows that the 3D framework of 1 can be abstracted into a ten-connected topological network. The volatile azido ion can be viewed as a counter anion to be stabilized in a 3D framework as the connection of Cd(II) ions with two independent atz− ligands still remains a 3D framework. Compound 1 has a high calculated density (ρ) of 2.517 g cm−3. The standard molar enthalpy of formation (ΔfHo) of 1 was calculated to be 1330.10 kJ mol−1, which is higher than those of most of the previously 3D energetic MOFs. Sensitivity tests demonstrate that 1 is insensitive to external mechanical stimuli. TGA demonstrates that 1 has an excellent thermostability which can be stable up to 372 °C. Compound 1 can be served as a high-energy-density material with a favorable level of safety due to its excellent energetic performances, low sensitivities and excellent thermostability.

Gastrodia elata is a kind of traditional Chinese medicinal materials and has good medicinal value. G. elata is divided into five varieties, which includes G. elata f. elata(proto variant), G. elata f. glauca, G. elata f. viridis, G. elata f. flavid and G. elata f. alba. Among them, G. elata f. elata and G. elata f. glauca have excellent characteristics and higher contents of gastrodin and polysaccharides. The hybrid of G. elata f. elata and G. elata f. glauca is present in markets, but the characteristics between hybrid and parent are not obvious and distinguished quickly and accurately. The aim of this study is to establish a PCR specific PCR identification method, which can identify G. elata f. elata, G. elata f. glauca and their hybrid. Based on the re-sequencing results of G. elata, we screened for the single nucleotide polymorphism(SNP) variation sites, and designed two pairs of specific primers(W291-F/W291-R and H255-F/H255-R). We further collected G. elata f. elata, G. elata f. glauca and their hybrid samples from different regions, established and optimized PCR method, and investigated and verified their tolerance and applicability. The results showed that when the annealing temperature was 48 ℃ and the number of cycles was 33, 255 bp specific band were obtained from G. elata f. glauca and hybrid by using specific primers W291-F/W291-R. When the annealing temperature was 51 ℃ and the number of cycles was 33, 291 bp specific band were obtained from G. elata f. elata and hybrid by using specific primers H255-F/H255-R. Our method could be used as a promising method to identify G. elata f. elata, G. elata f. glauca and their hybrid.

Background The ECG characteristics of simultaneous acute occlusion/sub-occlusion of two coronary arteries involving the left anterior descending (LAD) and right (RCA) coronary artery have been rarely described in the literature. Methods We present two patient cases, where one of the arteries was totally occluded and the other one had a sub-occlusion with severely limited flow to demonstrate the ECG characteristics of this severe presentation of acute coronary syndrome. Results Two ECG patterns suggested simultaneous occlusions of the RCA and LAD. One pattern was ST-segment elevation (STE) in lead III higher than in lead II with concomitant STE in leads V3-V4. The other pattern was STE in lead III higher than in lead II with the concomitant Dressler - de Winter ECG pattern in leads V2-V4. Conclusions We present two ECG presentations of simultaneous RCA and LAD occlusion/sub-occlusion. We consider these ECG features as high-risk markers in acute ST-elevation myocardial infarction.

This letter presents a novel methodology for resistive–resistive series of continuous class-F/ $\text{F}^{{\mathbf {-1}}}$ modes (Res.–Res. SCF/ $\text{F}^{{\mathbf {-1}}}$ Ms) power amplifier (PA) design. The bandwidth is expanded by designing the lower band with resistive second- and third-harmonic impedances and the upper band with resistive second-harmonic impedance and reactive third-harmonic impedance using a waveform engineering method. Mathematical derivation of the methodology is described in detail. The proposed design is experimentally verified using a Res.–Res. SCF/ $\text{F}^{{\mathbf {-1}}}$ Ms PA operating across 0.4–2.3 GHz with 62.3%–80.5% drain efficiency and 39–42 dBm output power.

This Letter presents a methodology, which contains resistive-reactive series of continuous inverse modes (Res.-Rea. SCIMs), for the second octave power amplifier (PA) design. The bandwidth was extended by multiplying the current waveform of SCIMs with a cosine factor. The measurement of the proposed Res.-Rea. SCIMs PA showed 67–78.8% drain efficiency and ∼10 W output power across a band of 0.5–2 GHz.

Aim: The aim is to evaluate serum cysteine-rich protein 61 (Cyr61) levels in patients with coronary artery disease (CAD). Patients & methods: Serum Cyr61 levels were measured in 180 patients with CAD and 74 participants without CAD. Results: Serum Cyr61 levels were significantly higher in CAD patients. Patients with acute coronary syndrome showed significantly higher Cyr61 than those with stable angina pectoris. Serum Cyr61 levels in complex lesion group were significantly higher. Serum Cyr61 was positively correlated with Gensini score and C-reactive protein. Multivariable logistic regression analyses demonstrated that serum Cyr61 levels were independently correlated with the existence of CAD (p = 0.01). Conclusion: Our study suggested Cyr61 as a potential biomarker in characterizing CAD and therapeutic target for CAD.

This paper researches on the kinematics and dynamics of coupling for three-axis flight Simulator based on the high-speed rotation missile. Firstly, to define station body coordinate and the positive direction of rotation according to three-axis flight Simulator based on the high-speed rotation missile, and then the mathematical coupling model is established. Secondly, multivariable nonlinear mathematical model can be decoupling, while substituting the parameters quality attribute analysis solved by ProE into the mathematical model. Lastly, the decoupled linear equations and the decoupling solutions based on inverse system method were given, and then to finish the simulation and to analysis the simulation results.

Brushless DC Motor (BLDCM) is a strongly nonlinear systems, which means that we can’t get a satisfactory result by the traditional PID Controller. This paper presents an improved BP Neural Network algorithm with adaptive adjustment of learning rate and range adjustment of the output. At last, using MatLab/Simulink to verify the algorithm that it has better control precision and adaptability.

The brushless DC motor (BLDCM) has many advantages. This paper first analyzes the work principle of BLDCM and the control methods of the fuzzy PID, then designs a triple-loop controller based on the fuzzy PID BLDCM, finally makes a comparison of the traditional PID method and this new method. The experiment result shows that the result of the PID controller based on the BLDCM is much better than the traditional PID controller, the BLDCM improves the performance both on the step response of the position and the sinusoidal steady state response.

In this paper, Newton's laws of motion and momentum theorem are the theoretical basis. The equations of motion in the vertical plane are the calculation basis. In order to get the ballistic and numerical solution of motion parameters of the missile, the Runge-Kutta method and matlab are used to solve the missile Trajectory. Firstly, this paper builds the trajectory model of missile in vertical plane. Secondly, this paper chooses missile control method. Thirdly, the Runge-Kutta method and matlab are used to verify the correctness. And to further analyze the law of motion parameters changed with time.

Effect of quenching process on the microstructure and mechanical properties of a kind of seamless tubes of steel 28CrMnMoV was investigated. Then, an investigation on the influence of two different quenching processes on the ductile-brittle transition behavior of this steel was undertaken. The ductile-brittle transition temperatures of the steel by two different quenching processes were also determined. The results show that a good combination of mechanical properties can be obtained through austenitizing experimental steel at 800 °C or 890 °C followed by tempering at 630 °C. Ductile-to-brittle transition temperature of 28CrMnMoV steel austenitized at 800 °C followed by tempering at 640 °C is about −73 °C, which is much lower than the value −37 °C when the steel was austenitized at 890°C and then tempered at 650 °C. This indicates that subcritical quenching process could decrease largely the ductile-to-brittle transition temperature of 28CrMnMoV steel.

Hot compression tests of modified 2.25Cr–1Mo steel were conducted on a Gleeble-3500 thermo-mechanical simulator at the temperatures ranging from 1173 to 1473 K with the strain rate of 0.01–10 s −1 and the height reduction of 60%. Based on the experimental results, an artificial neural network (ANN) model and constitutive equations were developed to predict the hot deformation behavior of modified 2.25Cr–1Mo steel. A comparative evaluation of the constitutive equations and the ANN model was carried out. It was found that the relative errors based on the ANN model varied from −4.63% to 2.23% and those were in the range from −20.48% to 12.11% by using the constitutive equations, and the average root mean square errors were 0.62 MPa and 7.66 MPa corresponding to the ANN model and constitutive equations, respectively. These results showed that the well-trained ANN model was more accurate and efficient in predicting the hot deformation behavior of modified 2.25Cr–1Mo steel than the constitutive equations.

Isothermal hot compression of 28CrMnMoV steel was conducted on a Gleeble-3500 thermo-mechanical simulator in the temperature range of 1173–1473 K with the strain rate of 0.01–10 s−1 and the height reduction of 60%. Based on the experimental results, constitutive equations and an artificial neural network (ANN) model with a back-propagation learning algorithm were developed for the description and prediction of the hot compressive behavior of 28CrMnMoV steel. Then a comparative evaluation of the constitutive equations and the trained ANN model was carried out. It was obtained that the relative errors based on the ANN model varied from −3.66% to 3.46% and those were in the range from −13.60% to 10.89% by the constitutive equations, and the average absolute relative errors were 0.99% and 4.09% corresponding to the ANN model and the constitutive equations, respectively. Furthermore, the average root mean square errors of the ANN model and the constitutive equations were obtained as 1.43 MPa and 5.60 MPa respectively. These results indicated that the trained ANN model was more efficient and accurate in predicting the hot compressive behavior of 28CrMnMoV steel than the constitutive equations.

Hot compression tests of T24 ferritic steel were carried out using Gleeble-3500 thermo mechanical simulator in the temperature range of 1323–1473 K with the strain rate of 0.01–10 s−1 and the height reduction of 60%. The flow behavior of T24 ferritic steel was characterized based on analysis of the true stress–strain curves. Constitutive equations incorporating the effects of temperature, strain rate and strain have been developed to model the hot deformation behavior of T24 ferritic steel. Material constants α, n, ln A and activation energy Q in the constitutive equations were calculated as a function of strain. The flow stress values of T24 ferritic steel predicted by the proposed constitutive equations show a good agreement with experimental results, which indicated that the developed constitutive equations could give an accurate and precise prediction for the flow stress of T24 ferritic steel.

The true stress–strain data from isothermal hot compression tests on Gleeble-3500 thermo mechanical simulator, in a wide range of temperatures (1323–1473 K) and strain rates (0.01–10 s−1), were employed to establish the constitutive equations based on modified Zerilli–Armstrong and strain-compensated Arrhenius-type models respectively, and develop the artificial neural network model to predict the high-temperature flow stress of T24 steel. Furthermore, a comparative study has been made on the capability of the three models to represent the elevated temperature flow behavior of this steel. Suitability of the three models were evaluated by comparing the accuracy of prediction of deformation behavior, correlation coefficient and average absolute relative error of prediction, the number of material constants, and the time needed to evaluate these constants. The results showed that the predicted values by the modified Zerilli–Armstrong model could agree well with the experimental values except under the strain rate of 0.01 s−1. The predicted flow stress of the other two models shows good agreement with the experimental data. However, the artificial neural network model could track the deformation behavior more accurately throughout the entire temperature and strain rate range though it is strongly dependent on extensive high quality data and characteristic variables and offers no physical insight.

The true stress–strain data from isothermal hot compression tests, in a wide range of temperatures (1173–1473 K) and strain rates (0.01–10 s −1 ), were employed to study the deformation behavior and develop constitutive equation of V150 grade oil casing steel based on an Arrhenius-type equation. The flow stress increases with the decrease of deformation temperature and the increase of strain rate, which can be represented by Zener–Hollomon parameter in an exponential equation. The influence of strain was incorporated in the developed constitutive equation by considering the effect of strain on material constants. The flow stress predicted by the constitutive equation shows good agreement with the experimental value through the whole experimental temperature and strain rate range except a slight deviation for predicting the stress deformed at 1173 K under 0.01 s −1 , and the average relative error is 4.21%.

The continuous rolling and sizing processes for producing non-quenching and non-tempering 36Mn2V steel pipes used in oil well were studied by the thermomechanical simulation test in this paper. The results showed clearly that the final microstructure was influenced by deformation temperature and stain applied. When continuous rolling temperature was controlled at 1050°C and strain at about 0.5 or above, dynamic recrystallization was completed and fine austenitic grain was obtained. When sizing temperature was controlled at 850°C or below and strain at about 0.2 or above, fine acicular ferrite was obtained with properties satisfying the requirement of the high quality pipe. The results of the study provided reliable data for the controlled rolling and sizing processes for the production of the 36Mn2V steel pipes.

Two industrial produced non-quenching and non-tempering steels 40Mn2V and 36Mn2V had been tested by Gleeble-1500 thermal simulation machine to simulate MPM rolling, sizing and cooling process. The cooling rate in the air noticeably affected the final property of different size pipes. According to the measured practical cooling rates of different size pipes, appropriate size pipes with cooling rate at range of 0.9°C/s~1.6°C/s and 1.6 °C/s~2.1°C/s can be picked out to use steel 40Mn2V and 36Mn2V to produce grade N80 OCTG(Oil Country Tubular Goods) with steady property respectively. This result had been used in practical production, which greatly improved the property stability of grade N80 OCTG.

In continuous tube rolling process, wall thickness reduction per stand will be changed due to wall thickness fluctuation of pierced shell caused by piercing process, which results in changes in metal flow conditions and affects force parameters, deformation parameters, especially transverse wall thickness precision of rolled hollow tube. In this paper, with the aid of commercial FE code MSC.SuperForm, the high pressure boiler steel tube continuous rolling process of a typical hollow tube specification 133.0×4.0mm are simulated based on 133 main pass sequence of 89mm 6-stand semi-floating mandrel mill, and force parameters, equivalent plastic strain, transverse wall thickness precision, outline dimension and real roundness of rolled hollow tube are analyzed and compared on the condition of two different wall thicknesses of pierced shell. Analysis results indicate that force parameters increase with wall thickness of pierced shell, maximal rolling force, rolling moment and mandrel axial force increase 10% or so in the first three stands when rolling pierced shell of wall thickness 11.5mm compared to that of wall thickness 10.5mm. When rolling pierced shell of wall thickness 10.5mm, there exist front and back tensions among the third, the fourth and the fifth stands and outline dimension and real roundness of rolled hollow tube is slightly better. However, transverse wall thickness of rolled hollow tube at the bottom of groove is pulled thin obviously.

In continuous tube rolling process, it has an obvious influence on the stability of rolling process, tools wear and the quality of rolled hollow tube that configuration of roll rotational speed per stand. In this paper, various roll working diameters per stand are determined by velocity integral method (VIT) and FEM respectively, and two roll rotational speed schedules are obtained correspondingly based on 133 main pass sequence of 89mm 6-stand semi-floating mandrel mill. With the aid of commercial FE code MSC.SuperForm, the high pressure boiler steel tube continuous rolling process of a typical hollow tube specification 133.0×5.2mm are simulated, and force parameters, transverse wall thickness precision, outline dimension and real roundness of rolled hollow tube and clearance between the mandrel and rolled hollow tube are analyzed and compared on the condition of two different roll rotational speed schedules, which provides scientific basis for configuring reasonable roll rotational speed per stand in pass design and optimization. Analysis results indicate that roll working diameter obtained per stand is smaller and roll rotational speed configured is higher correspondingly using FEM compared to VIT. Using FEM, there exist front and back tensions between stands and maximal rolling force, rolling moment and mandrel axial force decrease 10% or so in continuous tube rolling process, and outline dimension and real roundness of rolled hollow tube is better. However, transverse wall thickness of rolled hollow tube at the bottom of groove is pulled thin slightly, and clearance between the mandrel and rolled hollow tube is less than normal.

the aid of commercially available software MSC.SuperForm, a 3-D finite element model has been established to simulate the rolling process of steel tubes on the stretch reducing mill (SRM) with group centralized differential drive in certain factories. A special effort was made to analyze the fluctuation of transverse wall thickness uniformity. It was found that the wall thickness of each stand was accumulated in the original pass 50°~60° along the circumferential direction, which caused the formation of the inner hexagon defects and worsen. In view of this, this paper proposes a modified roll pass design method which uses the interactive technology of CAD graph curve and MATLAB equation. By means of decreasing the lateral curvature of roll pass contour curve to enlarge the contact length between the tube and groove, also the rolling process using the new pass system were simulated and analyzed. The results indicate that the design of such polygonal roll pass can be effective in improving the inner hexagon defects.

With the aid of commercial finite element analysis software MSC. Superform, the high pressure boiler steel tube continuous rolling process with 6-stand semi-floating mandrel is simulated, and the distribution characteristic of transverse wall thickness is analyzed. It indicates that it presents “M” shape that the distribution of transverse wall thickness of hollow tube along one-fourth groove periphery. Transverse wall thicknesses have low values at the top, the bottom and sidewall 45 degree or so of groove, and they have high values at the sidewall 23 degree and 67 degree or so of groove. Then the improved measure is put forward on the basis of analyzing the causes responsible for transverse wall thickness. By the comparison of the simulation results, they have been improved obviously that transverse wall thickness precision and real roundness of rolled hollow tube using the improved measure.

Chemotherapy is one of the major treatment methods for cancer. However, failure in chemotherapy is not uncommon, mainly due to dose-limiting toxicity associated with drug resistance. Management of drug resistance is important towards successful chemotherapy. There are many reports in the Chinese literature that natural products can overcome cancer cell drug resistance, which deserve sharing with scientific and industrial communities. We summarized the reports into four categories: (1) in vitro studies using cell line models; (2) serum pharmacology; (3) in vivo studies using animal models; and (4) clinical studies. Fourteen single compounds were reported to have antidrug resistance activity for the first time. In vitro, compounds were able to overcome drug resistance at nontoxic or subtoxic concentrations, in a dose-dependent manner, by inhibiting drug transporters, cell detoxification capacity, or cell apoptosis sensitivity. Studies in vivo showed that single compounds, herbal extract, and formulas had potent antidrug resistance activities. Importantly, many single compounds, herbal extracts, and formulas have been used clinically to treat various diseases including cancer. The review provides comprehensive data on use of natural compounds to overcome cancer cell drug resistance in China, which may facilitate the therapeutic development of natural products for clinical management of cancer drug resistance.

DC micro-grid, as a self-management grid form of integrating distributed energy systems with utility power systems, will efficiently realize the value and benefit of the distributed energy resources. In this paper,the DC micro-grid mainly consists of five parts: a PV source, a DC/DC converter, a battery energy storage unit, a bi-directional DC/DC, and a bi-directional DC/AC which is connected to the main grid. This DC micro-grid has different control strategies according to different operating modes (grid connected, islanded). Then its control mode is designed and investigated by MATLAB/Simulink models. The simulation results verify the validity of the mathematical model and the feasibility of the proposed control strategies. In the grid connected mode, the transfer energy can flow in bi-directional modes, and DC bus voltage level can be stabilized by DC/AC converter. In the islanded mode, the battery converter serves as a voltage source to ensure a stable DC voltage. At last, DC micro-grid experimental system is used to examine its switching functions among different control modes. The experimental results demonstrate that high quality power can be supplied.

To evaluate the long-term protective effects of hepatitis B vaccine after immunizing to the children for 12 years in Beijing.The multiple stratified cluster sampling was used in this epidemiological survey. The sampling children's blood serum HBsAg, anti-HBs and anti-HBc were checked and measured by the solid phase radioimmunoassay (SPRIA). The serological level of these index and the causes of the children with HBsAg positive were analyzed.There were 2,419 cases 3-12 years-old children immunized with the hepatitis B vaccine in infant period were surveyed and the total HBsAg positive rate was 0.52%. The vaccine protective rate was 88.45% (95% CI: 65.67%-97.89%). The total anti-HBc positive rate was 2.21%, being no statistical significance among the age groups. The average anti-HBs positive rate of 3-6 years-old children immunized with gene recombining vaccine was 38.79% and descending greatly following the age's dropping. The geometric means of anti-HBs serological titer (GMT) was 52.83 mIU/ml, showing no statistical significance among the age groups. The average anti-HBs positive rate of 6-12 years-old children immunized with the blood rooting vaccine was 50.79%. The geometric means of anti-HBs serological titer (GMT) was 61.51 mIU/ml. There were no statistical significances among the age groups. Among the HBsAg positive children, more than 50% of the children's mothers were HBsAg positive also.The protective effects given by immunization were significant after the hepatitis B vaccine vaccination for 12 years in Beijing. The booster immunization was not necessary, because the HBsAg positive rate didn't ascend obviously as the immunization time prolonging. As the anti-HBs positive rate of children who were immunized by the gene recombining vaccine might be descending following the age's dropping greatly, we should strengthen the serological surveillance of hepatitis B. The main cause that the children became the HBsAg carrier should be a vertical transmission.

To evaluating the epidemiological effect after hepatitis B immunization among youngsters in Beijing.A multistage sampling method was used for data collection from immunization cards, reports on field epidemiological survey on hepatitis B virus (HBV) immunization of youngsters and the analysis of infectious diseases. HBsAg, anti-HBs and anti-HBc levels were detected by solid phase radioimmunoassays (SPRIA).The average incidence rates of hepatitis B in 10 - 19 years-olds prior to HBV immunization was 12.11-16.89/100 000, while declined to 1.78-10.95/100 000 (chi(2) = 10.71 - 60.45, P0.01). HBsAg carrying rate of the youngsters decreased from 6.34% to 1.37% (80.00%) after vaccination (chi(2) = 14.16, P0.01).Hepatitis B vaccination among youngsters is an effective measure for the prevention and control of hepatitis B virus infection.

To evaluate the epidemiological effect of hepatitis B immunization among newborn babies in Beijing.A multistage sampling method was used for the collection of immunization cards, field epidemiological survey on hepatitis B virus (HBV) immunization of children, analysis of infectious disease reports. HBsAg, anti-HBs and anti-HBc levels were detected by solid phase radioimmunoassays (SPRIA).The incidence of hepatitis B in children of 0 to 14 years at the beginning of HBV immunization was 18.59 to 20.52/100,000, and declined to 0.39 to 2.38/100,000 in 2000 (chi2 = 58.26, P0.01). The HBsAg carrying rate of the children decreased from 2.82% to 0.60%, about 80.00% after vaccination (chi2 = 10.75, P0.01).Hepatitis B vaccination of newborn babies is an effective measure for prevention and control of hepatitis B virus infection.