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A large number of efficient cyanation methods have been developed because of the wide range of applications of nitriles, but conventional methods usually suffer from the need for a toxic cyanation reagent. Although difluorocarbene chemistry has received increasing attention, the use of difluorocarbene as a sources of the nitrile carbon for nitrile groups remains largely unexplored. We describe a difluorocarbene-based cyanation of aryl iodides promoted by a cheap copper source, Cu(NO3)2·2.5H2O, under an air atmosphere. Ph3P+CF2CO2 –, an easily available and shelf-stable difluorocarbene reagent, and NaNH2 are used as the carbon source and the nitrogen source for the nitrile group, respectively. The cyanation protocol is attractive because no toxic reagent is used and performing the reactions under an air atmosphere is operationally convenient.

We choose the optimal cross-sectional shape of the polymer five-lumen catheter products as the goal, and the simulation and experiment of extrusion process parameters were carried out. Firstly, the effect of gas injection pressure and extrusion rate on the extrusion expansion ratio, and the influence of gas injection pressure, extrusion rate and traction speed on the cross-section size, was studied by using Polyflow software; The effects of gas injection pressure, extrusion rate and traction velocity on the five-lumen catheter were studied, the experimental results are compared with the numerical simulation results. The optimal combination of the parameters of the extruded five-lumen catheter is obtained by orthogonal experiment, I.e., the head temperature T = 210 °C, injection pressure P = 4515Pa, the extrusion rate v = 4.5mm / s, pulling speed vp = 33.83mm / s; The corresponding relative error is: Primary lumen relative error Y1 = 3.46%, secondary lumen relative error Y2 = 3.33%, the minimum relative error lumen Y3 = 1%, the outer contour relative error Y0 = 0.61%.

With the development of smart grid, and ever-increasing kinds of electrical loads, the power system requires current measurement technology with wider measurement range, this thesis designs a new type of current sensor based on Giant magnetoresistance (GMR) material. Firstly, this thesis introduces principles and characteristic of GMR current sensor. For the shortcomings of low sensitivity and poor linearity of GMR chip, this thesis presents a structure of open-loop current sensor using GMR chip as magnetic probe, which improves the sensitivity of sensor effectively. Based on the open-loop GMR current sensor structure, a closed-loop GMR current sensor design is proposed. This design compensates the magnetic field through the feedback circuit and improves the accuracy and dynamic measurement range of GMR current sensor. Finally, we tested the GMR sensor system we developed, include DC characteristic test and AC characteristic test, it shows the current sensor has the capability of high dynamic current measurement.

The apparent resistivity of the induced electromotive force observed by the transient electromagnetic (TEM) in center loop is proposed by using the neural network. According to the characteristics of increasing of the induced electromotive force with the resistivity of the transient electromagnetic sounding, the neural network input and output relationship and the network structure of the transient electromagnetic induction electromotive force response are designed according to the uniform half space central line observation mode. The nonlinear model of transient electromagnetic induction electromotive force and apparent resistivity is fitted by the neural network to obtain the full apparent resistivity value of the measured induced electromotive force data at a certain sampling time, and the aim of resistivity and imaging is achieved quickly. Through the calculation and verification of the simulation model of the transient electromagnetic in grounding grids, the apparent resistivity section can be obtained, and the position of the breakpoint can be clearly determined, and the effect of solving the inverse problem is achieved. The calculation of the verification model shows that the method makes the calculation time of the transient electromagnetic apparent resistivity greatly shorten, which is a practical algorithm.

Polysaccharide from the seeds of Plantago asiatica L. was given via oral administration to mice (0.4 g/kg body weight, 30 days) to observe its effects on mouse nutrient metabolism and colon microbiota. It was found the polysaccharide intake could lower the apparent absorption of lipid. Total triglyceride, cholesterol, and atherogenic index in blood serum with total lipid and cholesterol levels in liver of polysaccharide group mice were all significantly lower than those of the control group (p < 0.05). Furthermore, the effect of the polysaccharide intake on mouse colon bacterial communities was investigated. Mice from the polysaccharide group showed a higher colon bacterial diversity than the control group. Bacteroides sp., Eubacterium sp., butyrate-producing bacteria Butyrivibrio sp., and probiotics Bifidobacterium bifidum , Lactobacillus fermentum , and Lactobacillus reuteri in mouse colon were all increased after polysaccharide intake. These indicated that the intake of polysaccharide from P. asiatica L. could be beneficial for lipid metabolism and colon microbiota.

Effects of microwave irradiation on microbial short-chain fatty acid production and the activites of extracellular enzymes during in vitro fermentation of the polysaccharide from Plantago asiatica L. were investigated in this study. It was found that the apparent viscosity, average molecular weight, and particle size of the polysaccharide decreased after microwave irradiation. Reducing sugar amount increased with molecular weight decrease, suggesting the degradation may derive from glycosidic bond rupture. The polysaccharide surface topography was changed from large flakelike structure to smaller chips. FT-IR showed that microwave irradiation did not alter the primary functional groups in the polysaccharide. However, short-chain fatty acid productions of the polysaccharide during in vitro fermentation significantly increased after microwave irradiation. Activities of microbial extracellular enzymes xylanase, arabinofuranosidase, xylosidase, and glucuronidase in fermentation cultures supplemented with microwave irradiation treated polysaccharide were also generally higher than those of untreated polysaccharide. This showed that microwave irradiation could be a promising degradation method for the production of value-added polysaccharides.

In order to analyze inter-harmonic parameters accurately, a new detecting method was proposed on the basis of nonlinear optimization and AR modern spectral estimation. The AR model was used to produce a rough estimated value of harmonic parameters and then the signal model was set. By using the optimization algorithm which based on damped nonlinear least squares method and conjugate gradient method, the parameters can be estimated more accurately. The combined method not only solves the problem of inaccurate estimate by AR power spectrum analysis, but also solves the problem of how to set the signal model and to choose initial value. The simulation results show that in noisy environments, this method is effective and the accuracy which is 101 to 104 times higher than the interpolation Hanning window method.

The olivine LiMnPO4 used as cathode materials was synthesized by the low combustion synthesis method, and modified by doping Y. Testing of X-ray diffraction (XRD),scanning electron microscopy (SEM),charge-discharge measurements was carried out for LiMnPO4/C cathode materials and the modified materials. The synthesized materials doping by Y exhibited standard olivine structure, nano-sized particles, discharge capacity of 122.9mAh.g-1 and good cycling performance. These results indicated that less Y doping could improve electrochemical kinetics of lithium ion extraction/insertion and significantly enhanced electrochemical activity.

Some modifications of conventional neuron proportional-integral-differential controller (NPID) are presented in this paper to prevent its slow dynamic response and loss of control in case of improper learning factors. The quasi-step signal replaces the step signal as the reference signal to improve the dynamic characteristics. The control output of NPID is modified every step by multiplying a penalty factor called senior teacher signal to suppress further the overshoot and compress the settling time. The steady-state error from the modified NPID (MNPID) is reduced or removed by adjusting dynamically reference input signal while excluding the pseudo steady state. Lots of simulation experiments are done to prove the stability and convergence of the MNPID control algorithm.

Cr-α-Al2O3composite coatings were prepared by direct current deposition experiments from Cr(Ⅲ) plating bath and the thickness of composite coatings could be up to 14 μm. The obtained Cr-α-Al2O3coatings and Cr coatings were characterized by means of EDS, SEM and microhardness measurement. Results revealed that Cr-α-Al2O3coatings exhibit fine-grained structure with uniform surface and the highest microhardness values(692 HV) when the α-Al2O3content of coatings was 15g/L, although some pores and defects are still present in the coatings. Analysis of Tafel curves indicated that the presence of α-Al2O3in the Cr coatings show better features in the corrosion resistance both in H2SO4and NaOH solution than those prepared from the bath without α-Al2O3.

A systematic solution method to obtain the five-parameter model of the photovoltaic (PV) solar cells (modules or arrays) in case of only the few data ( V oc , I sc , V mp , and I mp ) available from the manufacturers. To preset the proper initial values (such as R sh ) within their ranges and select the proper iterative expressions when solving the nonlinear equation system through a concise computer procedure, the basic ranges of parameters are defined and the sensitivities of parameters are graphically analyzed on condition that as few simplifications as possible are made. The stability and effectiveness of the solved five parameters are kept and the convergence is very fast owing to the automatic error corrections during iterative computation. The resultant I – V and P – V characteristics and the experimental results are almost unanimous and show small errors, especially near the maximum power point.

This paper presented the composite coatings of nickel with graphite particle on the aluminum substrate using a nickel sulfamate bath. Effects of graphite particle concentration on the surface morphologies of the composite coatings were investigated. The inclusion of graphite particle into metal deposits was dependent on many process parameters, including particle concentration, current density, pH and temperature. Results of SEM and XRD demonstrated that graphite particle had successfully deposited on that nickel matrix; besides, the surface morphology of coatings obtained from sulfamate bath containing 2g/L graphite particle dispersed more uniformly than the ones with higher concentration.

The shape change in microprofile extrusion was investigated using a capillary rheometer with two different die orifices:a trilobal and a elliptic orifice. The material used in extrusion was fiber-grade polypropylene. The result showed that during microprofile extrusion the shape of extrudate deviated greatly from that of the die orifice. The size of extrudate increased with the increase of the extrusion speed and temperature but decreased with the increase of the drawing speed. Furthermore, water cooling was found to be beneficial in reducing shape change. For the trilobal shape, the shape change of trilbolal leaf in the width direction was much larger than that in the length direction. For the elliptic shape, the shape change along the minor axis was larger than along the major axis.

In this paper, improvement in the method for purifying glycoprotein from green tea ( Camellia sinensis ) was described; some properties and chemical compositions of tea glycoprotein (TGP) were determined by HPGPC, FT-IR, GC–MS technologies. Compared to existing methods, a more compatible method for purifying TGP was proposed. This method was faster, simpler, more effective and easier to be extended to the industrial production than the method that used in our previous work. The molecular weight of TGP was 126,513 Da using HPGPC. GC–MS analysis of TGP showed that TGP was composed of seven kinds of monosaccharides, namely ribose, rhamnose, arabinose, xylose, mannose, glucose, galactose in molar ratios of 1.71:5.88:13.70:1.99:1.00:1.84:33.75. Eighteen amino acids were identified in TGP by amino acid analysis. The FT-IR spectrum of the TGP revealed also typical characteristics of polysaccharides, protein and uronic acid.

To investigate the relationship between the expression of uncoupling protein 2 (UCP2) and ratio of interleukin-10/interferon-gamma (IL10/IFNgamma) in the macrophages from patients with unexplained recurrent spontaneous abortion (URSA).Twelve women undergoing selective termination of normal early pregnancy (control) and 11 having URSA were included in this study. Magnetic cell sorting (MACS) was used to isolate the macrophages in the decidua, and the expression of UCP2 was detected with flow cytometry. Cytokine (IL10 and IFNgamma) secretion by the macrophages was detected by enzyme-linked immunosorbent spot-forming (ELISPOT) cell assay.Compared to the control group, the women with URSA showed significantly decreased expression of UCP2 on decidual macrophage (136-/+25 vs 201-/+31, P0.01), and the expression of UCP2 was positively correlated to the ratio of IL10/IFNgamma(r=0.73, P0.01).UCP2 may play an important role in the regulation of macrophage activity and cytokine secretion to contribute to spontaneous abortion.

Germ cells are much more susceptible to oxidative stress than somatic cells. Accumulating evidence indicates that uncoupling protein 2 (UCP2) prevents the apoptosis of multiple types of cells induced by reactive oxygen species (ROS). The present study aimed to evaluate the protective effect of uncoupling protein 2 (UCP2) against oxidative damage to human sperm.Semen parameters were obtained from 97 semen samples by computer assisted sperm analysis (CASA), and the samples, based on the percentage of grade a + b sperm, allotted to Groups I (n = 25, grade a + b sperm50%), II (n = 24, grade a + b sperm 25%-50%), III (n = 24, grade a + b sperm 10-25%) and IV (n = 24, grade a + b sperm10%). The expressions of sperm UCP2 mRNA was detected by RT-PCR, and the malonaldehyde (MDA) content in ROS was determined in the sperm suspension.The expressions of UCP2 mRNA in sperm were 1.51 +/- 0.24, 1.28 +/- 0.15, 1.17 +/- 0.20 and 0.69 +/- 0.18, and the MDA contents were (14.66 +/- 2.55), (16.00 +/- 2.09), (17.44 +/- 1.40) and (21.20 +/- 3.50) nmol/10(8) sperm in Groups I, II, III and lV, respectively. There was a significant negative correlation between the expression of UCP2 mRNA and the content of MDA (r = -0.633, P0.01), the former obviously reduced while the latter remarkably increased in the groups of lower sperm motility (P0.01).UCP2 plays an important protective role against oxidative stress damage to human sperm by diminishing ROS production.

To evaluate the clinical and endocrine effectiveness of different laser doses for ultrasound-guided transvaginal ovarian interstitial laser treatment in patients with polycystic ovary syndrome (PCOS).Between January 2005 and July 2007, 56 women with clomifene citrate-resistant PCOS selected from the patients who were referred to Shenzhen Maternity and Child Healthcare Hospital with a request for fertility underwent ultrasound-guided transvaginal ovarian interstitial laser treatment. All subjects were randomly divided into four groups of A, B, C and D. In group A, one coagulation point per ovary was done and group B, two points; group C, three points; group D, four to five points. The size of each point was about 10 mm in diameter (the electrical laser was projected persistently for 1-3 min with a power of 3 -5 W). The serum sexual hormone level, ovulation rate and pregnancy rate within six postoperative months were compared among the four groups.(1) The spontaneous ovulation rates of groups A (0) and B (21%) within six postoperative months were significantly lower than groups C (71% ,P0. 05) and D (79%, P0.01). The accumulative pregnancy rates of group C(43%) and D(36%) for six postoperative months were significantly higher than group A (0; P0.01, P0.05). Although they were also higher than that of group B, no statistical significance was found (P0.05). (2) No statistically significant differences were found among four groups when various preoperative hormone values were compared (P0. 05). The mean serum luteinizing hormone (LH), testosterone level and LH/ follicle stimulating hormone (FSH) ratio was significantly lower postoperatively in groups C [(6.3 +/- 2.6) U/L, (2.2 +/- 0.7) nmol/L, 1.1 +/- 0.3] and D [(5.8 +/- 2.5) U/L, (2.1 +/- 0.4) nmol/L, 1.0 +/- 0.4] than in groupsA [(11.9 +/- 3.1) U/L, (3.9 +/- 1.6) nmol/L, 2.1 +/- 0.5] and B [(10.4 +/- 3.9) U/L, (3.3 +/- 1.1) nmol/L, 2.0 +/- 0.6], respectively (P0.05). The mean LH, testosterone level and LH/FSH ratio reduced more obviously in groups C (42%, 39% and 42%) and D (53%, 40% and 58%) than in groups A (4%, 9% and 16%) and B (11%, 6% and 5%; P0.05). All above-mentioned parameters between groups C and D had no statistical significant difference (P0.05).One and two intraovarian laser coagulation points per ovary are associated with poor results. Three points per ovary seem to represent the plateau of effective dose for the ovarian interstitial laser treatment. Increasing the dose above it does not improve the outcome.

In this paper, the contents of elements Se, Zn, Mn, Cu, Mg, Fe, Al and Be in the plantago, originating from different places and produced with various methods, were determined by ICP-AES technique. Its recovery ratio obtained by standard addition method ranged between 80.4% and 119.7%, and its RSD was lower than 6%. The results of the determination show that the seeds in plantago are rich in the inorganic elements such as Mg, Fe, Al and Zn essential to human health.

To study the expression of uncoupling protein 2 (UCP2) mRNA and protein in the endometrium and its changes during periimplantation period in relation to infertility.In situ hybridation and Western blotting were used to detect 21 endometrium specimens from normal cycling women during different menstrual phases, 22 secretory endometrium specimens from infertile women and 7 decidual and chorionic villus specimens.UCP2 mRNA and protein were detected in the endometrium and decidua besides, the trophoblast, and UCP2 level in the endometrium increased during pregnancy. Compared with normal women, women with hydrosalpinges had significantly stronger endometrial UCP2 expression in the mid-luteal stage.UCP2 down-regulates reactive oxygen species and plays a role in the regulation of inflammatory events to prepare for embryo implantation. Strong endometrial UCP2 expression might be an important reason that hydrosalpinges affect embryo implantation.

OBJECTIVE: To explore the effect of estradiol and progesterone on the expression of calcitonin in human endometrial epithelial cells cultured in vitro. METHODS: Human endometrial epithelial cells were cultured in vitro in DMEM medium. After the cells were treated respectively with estradiol and progesterone at different concentrations for 24 and 48 h, the fluorescence density of the cells was measured by flow cytometer. RESULTS: Progesterone treatment of the epithelial cells for 24 h produced in a dose-dependent manner significantly higher fluorescence level than that of the control (P0.01). Small dose of estradiol took little effect on calcitonin expression, but high-concentration estradiol resulted in lowered fluorescence level than the control. CONCLUSION: Progesterone promotes calcitonin expression in cultured human endometrial epithelial cells in a dose-dependent manner, while estradiol tends to inhibit its expression.