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As flame-retardant Polyacrylonitrile (PAN) fibers was one of the most important differential fibers, it was of great importance to make research on the modification of flame-retardant PAN fibers to improve its characteristics. In this present study, the flame-retardant PAN fiber with good moisture absorption and mechanical properties has been prepared treated by blending solution of sodium hydroxide and hydrazine hydrate. FTIR spectra presented that new amide and cyclization-crosslinking pyridine group band peaks appeared. X-ray diffraction showed that the crystal structure of PAN fibers has been converted from quasi-crystalline structure into partially crystallized structure after modification treatment. SEM micrographs indicated that the original longitudinal surface microgroove has changed to layered structure by surficial etchant.

A dumbbell-shaped polyrotaxane based on polytetrahydrofuran bis (3-aminopropyl) terminated and α-cyclodextrins using polyamidoamine (PAMAM) dentrimers as bulky stoppers was successfully prepared. The1H NMR results show that the peaks of α-CDs in these polyrotaxanes are broadened compared with pure α-CDs. Wide-angle X-ray diffraction (XRD) measurements of the resulting polyrotaxanes suggest to produce a channel-type crystalline structure of inclusion complex. Thermogravimetric analysis (TGA) of the resultant polyrotaxanes show that α-CDs are significantly stabilized by the formation of the inclusion complexes.

Melamine formaldehyde (MF) resin and its derivatives are always considered to be an excellent flame retardant material, which has a wide application in the flame retardant fabric, thermal insulation and high temperature filter Materials etc. The melamine formaldehyde resin (MF) and polyvinyl alcohol (PVA) blend electrospinning were studied in this work. MF-PVA electrospun fiber membrane was successfully prepared, and the limit oxygen index (LOI), scanning electron microscopy (SEM), infrared spectrum (IR) and X-ray diffraction (XRD) have been used to analyze and characterize the fiber. The results show that: The blending fiber is endowed with effective flame retardant property by the amino group and triazine ring group in MF/PVA fibers, and the LOI reaches 28~31. The MF and PVA blend fiber showed best uniformity when the blending solid content ratio of MF-PVA is 1:1. MF/ PVA blend fiber has certain crystallization capacity, which influences both the mechanical properties and flexibility of blending fiber.

Melamine formaldehyde (MF) resin and its derivatives are always considered to be excellent flame retardant material, which has wide application in the flame retardant fabric, high temperature insulating filter materials, etc. However, less research on electro-spinning of melamine fiber has been reported, recently. In the study, the molar ratio, condensation polymerization temperature of formaldehyde and melamine, and the law of effect in different solid content ratio of melamine formaldehyde/polyvinyl alcohol on the electro-spinning were studied. The results showed that the best conditions for spinning were that formaldehyde and melamine molar ratio was 1:1.7, the reaction temperature was 80°C, and the MF-PVA blending solid content ratio was 1:1, meanwhile the morphology of Electron microscopy indicated the good uniformity of the fiber. The fiber presents good flame retardant property in conditions of MF-PVA blending solution viscosity 155mPa ́s, limit oxygen index 33.2%.

Physical and chemical properties were measured to study quality of 5 strawberry cultivars, which were fruit weight, firmness, vitamin C, total sugar, total anthocyanin, total phenols, pH, total soluble solid, titratable acid, crude protein and juice yield. The result showed that PC1 explained 54.519% of the total variance in the data set, PC2 explained 28.184% and PC3 explained 9.252%. Accumulative variance contribution of these three main compositions extracted by principal component analysis was 91.954%. Eleven properties could reduce to three main components, and five strawberry cultivars were distinguished based on PC scores.

The chromatographic analysis of gas dissolved in oil can monitor transformer operation state at any time.It will help to find out transformer latent fault.The chromatogram analysis of locomotive transformer oil mainly adopts the improved three-ratio method.This paper introduces the improved three-ratio method and chromatogram analysis steps,through the concrete example,shows that the improved three-ratio method for transformer fault diagnosis result is basically matched with the actual fault reason,and summarizes attentions.

In order to solve the potential safety problem due to the explosion of coal mine caused the severe deformation of the front door not being opened normally and the emergency escape hatch was designed unreasonably, three types of structure model with emergency escape hatch being set in transition compartment as entrance and different locations of life supporting compartment as exit, which can avoid the potential safety problem above mentioned. Numerical simulation of antiknock impact performance of the three refuge cabins were calculated and analyzed by using the finite element software of LS-DYNA.The results indicated that the antiknock performance of structures could reach specifications, which could provide a new idea for the development of mine refuge chamber cabin.

In this paper, near-infrared diffuse reflectance spectroscopy was used to analysis the acteoside content of Radix Rehmanniae. The quantitative calibration models of acteoside content were established by the partial least square (PLS). The results showed that the correlation coefficient of calibration (R2) was 0.98102, the root-mean-square error of calibration (RMSEC) was 0.00464, the root-mean-square error of prediction (RMSEP) was 0.00163, and the average recovery rate was 104.837%. So the recovery of prediction set was available. The results indicated that it was available to determine the content of actoside in Radix Rehmanniae by near-infrared spectroscopy.

In this paper the water extract of Radix Rehmanniae from genuine producing area was rapidly determined by near-infrared spectroscopy (NIRS). The quantitative analysis model of the water extraction of Radix Rehmanniae was established by Partial Least Square (PLS). The correlation coefficient of calibration (R2) was 0.99529; the root-mean-square error of prediction (RMSEP) was 0.134. The results indicated that the water-soluble components in Radix Rehmanniae from genuine producing area can be rapidly and accurately determined by near-infrared spectroscopy technology.

Traditional Chinese medicine(TCM) preparation has a long history in China，and now it is an important direction at the development of hospital preparations, because lacking of quality control technology, quality of the different production batch is not quite stable in the process of production. Therefore, to establish perfect, accurate, rapid quality evaluation method is the key to realize modernization of the traditional Chinese medicine preparation[1,2]. The paper establishes the quantitative analysis model for Tanshinone IIA in Jingutongxiao Pills by near-infrared spectral technology. Through the discussion of spectral wavelength, spectral pretreatment and principal component count, it was found that the second derivative combined with partial least squares (PLS) establishes a best quantitative calibration model. The correlation coefficient of calibration (R2)was 0.975 37, the Root Mean Square Error of Cross Validation (RMSECV) is 0.001 17 and the external prediction deviation (RMSEP) is 0.00174. It indicated that the near-infrared spectral technology could be used for rapid, accurate, nondestructive determination of Tanshinone IIA in Jingutongxiao Pills[3,4].

To determine the Diosgenin in Dioscorea zingiberensis C.H.Wright by near-infraed spectroscopy (NIRS) combined with TQ software. The near-infrared sprectra and HPLC values of the Diosgenin in Dioscorea zingiberensis C.H.Wright from different areas were collected, and the quantitative calibration model was established with TQ software. And then the prediction samples were anylized by the model. The correlation coefficients (R2), the root-mean-square error of calibration (RMSEC) and the root-mean-square error of cross-validation (RMSECV) of the quantitative calibration model for diosgenin were 0.96459, 0.0999 and 0.30041 respectively; the correlation coefficients of prediction (r2) and the root-mean-square error of prediction (RMSEP) were 0.9634 and 0.128. The method is fast, convenient, non-polluted and accurate. The correction model could be used to predict the diosgenin in Dioscorea zingiberensis C.H.Wright.

In this paper, Near-infrared spectrum technology was applied for fast determining the content of magnolol and honokiol in Mangnolia officinalis. 105 samples of Mangnolia officinalis from xx pharmaceutical factories were divided into a calibration set (79 samples) and a validation set (26 samples). The near infrared spectrum of samples were collected, while take the HPLC value as a reference, Use the partial least squares (PLS) to establish the quantitative model of Magnolol and Honokiol. The correlation coefficient of calibration (R2), the root-mean-square error of calibration (RMSEC) and the root-mean-squareerror of cross-validation (RMSECV) of the calibration model were 0.9813, 0.0833, 0.2518; the recovery rate of prediction of the validation was 99.99%.The method is uncomplicated and result is accurate, which could measure the content of Mangnolia officinalis in bulk and fast, save costs and improve efficiency.

Physical and chemical characterization of 6 apple varieties (Early Golden Delicious, Jonagold, Hanfu, Ralls, Rainier and Fuji) from China was performed using pattern recognition tools. Measurements were taken on 12 parameters including weigh, colour, fruit firmness, crude fiber, total soluble solids, titration acid, water, Vitamin C, edible rate and juice yield .The results showed that physical and chemical properties existed different variance in apple varieties. The coefficient of variance of 12 properties was from 2.15% to 69.04%. The different apple varieties were investigated by principal component analysis (PCA) and hierarchical cluster analysis (HCA). PCA revealed that the first four components represented 95.13% of the total variability in properties and different apple groups. HCA classified samples into three groups on the basis of the physical and chemical properties.

Today, near-infrared (NIR) has been proved to be a powerful analytical tool. It has been applied widely in agricultural, petrochemical, textile and pharmaceutical industries. In this paper, near-infrared spectroscopy (NIRS) combined with partical least square (PLS) was used as a qualitative tool to rapidly determinate two active components in Fructus Corni. The PLS calibration model of NIR Spectroscopy, the correlation coefficients (R2) of Loganin and Morroniside were 0.95895 and 0.98450, the root-mean-square error of cross-validation (RMSECV), the Correction of deviation, the prediction mean square error was 0.0344,0.109;0.0625, 0.2641 and 0.0948, 0.233. The result shows that, the near-infrared Reflectance Spectroscopy could be used to determinate the content of Loganin and Morroniside, and meanwhile as a simple and rapid new method for the quality assessment of Fructus Corni. In addition, the NIRS has a unique advantage in the quality control of traditional Chinese Medicine (TCM), such as rapid, accurate, nondestructive and no pollution. It is expected to be further uses in the quality control of TCM. It is can achieve the requirement of rapid detection of large quantities of Fructus Corni.

A rapid determination method was builded about content of dioscin in Dioscorea zingiberensis C. H. Wright by near-infrared spectroscopy (NIRS) technology. The calibration model were builded through comparison of the content of dioscin in Dioscorea zingiberensis C. H. Wright and the near infrared spectroscopy of Dioscorea zingiberensis C. H. Wright with partial least squares. The internal correlation coefficient of cross-validation (R2) was 0.99208, root-mean-square error of cross-validation (RMSECV) was 0.0104, and external root mean square prediction deviation RMSEP was 0.0105, and the predictive value of the aversge relative error was 4.12%.

The objective of the present research was to establish a rapid analytical method for paeoniflorin and moisture in Xiaoyao Pills (condensed) by near-infrared spectroscopy. The near-infrared spectral data of 97 samples was collected by Nicolet 6700 NIR spectrograph,and the reference value of index component content were obtained by HPLC and oven-drying method. Then the multivariate calibration model of paeoniflorin and moisture were established by patrical least square (PLS) and predicting the content of unknow samples. The results showed that the correlation coefficients (R2) of the quantitative calibration model for paeoniflorin and moisture were 0.99774,0.95352, the root-mean-square error of calibration (RMSEC) were 0.00489,0.132,the root-mean-square error of prediction (RMSEP) were 0.00827,0.177. The results indicated that NIRS can provide a simple and accurate way for the fast determination of index component in large numbers of Xiaoyao Pills (concentrated).

On the basis of the construction of index system, by the factor analysis and the model of coupled coordination degree, the coupled coordination degrees in 2005 and 2010 between development of urban land intensive use system and social economic system are studied in 17 ground level cities of Shandong province. The first results showed that f (x) and f (y) in 2010 were higher than in 2005, which indicated that the degree of urban land intensive use and development level of the social economy were improved. The second results was that the coupled coordination degree of two systems was higher than in 2005, but if f (x) and f (y) were smaller, the gap in the capacity of comprehensive coordination was larger, the coupled coordination degrees were the smaller. So comprehensive development levels in single system were improved, which could not promote positive development between two systems.

To detect the sanitary status of pure water at different times in the campus, including to detect the total bacterial count, the coliforms, mould and yeast, this document explained and demonstrated the sanitary status of the barreled pure water through water dispensers. By the experiment, the results showed that the drinking fountain caused the pure water pollution, so the unheated pure water flowing though the drinking fountain were not qualified. And the longer the pure water samples were cultured, the more the aerobic bacterial count of water samples significantly exceeded the standard. After these samples were cultured for five days, all samples had be uncountale.

In order to predict accurately gas concentration and design ventilation scheme in driving ventilation process under different gas emission in coal mine, based on the analysis of various ventilation factors, the prediction model structure of gas concentration for driving ventilation was designed based on RBF and BP neural network in this paper. Then MATLAB software and the observation data obtained from the coal mine sites were used to compare and analyze the prediction errors of two models, and a RBF neural network model with higher prediction precision was obtained. After that, the prediction model was used for practical application research on the gas concentration of the heading face in concrete coal mines. The research shows that the settled prediction model can not only predict the gas concentration precisely of driving ventilation, but also provide a certain theory basis for different driving ventilation equipment layout and parameters configuration in the driving ventilation process of coal mines.

21st century is a century of life science and biotechnology. The modern biotechnology focusing on the genetic engineering has a rapid development, which plays a significant role in the solutions to the various coming problems of resources, environment, agriculture and medicine, etc. However, the conflict between biological engineering and ethical virtue has been an unavoidable problem, so how to strengthen the ethical virtue’s standardizing role to technique is the pressing matter of the moment. We have to have a clear understanding of the ethical virtue problems which are related to biological genetic engineering, and establish a full, scientific, tight policy as well as laws, ethical virtue requirements and mechanism to promote the development of the technology’s active role. In the 21st century, biotechnology has been a key technology that is used to solve the economic and social problems of food, resources, and environment and so on; thus, biotechnology industry has become one of the domestic pillar industries to reflect a country’s comprehensive national power. Different from any one of the previous technology breakthroughs, the objects that modern biotechnology is cognizing and transforming are human closely related biological area ——microorganism, plants, animals and even we human beings. Biotechnology has widely penetrated into kinds of fields such as medicine, biology, industry and agriculture; gene drugs, gene treatment and transgenic animals and plants all has been developing rapidly. Therefore, there is a qualitative leap in man’s cognition of biological phenomena, and human beings has reached a new height and stand on a new starting point to discuss the significance and value of life.

Firstly the research situation for grid-connected photovoltaic (PV) is introduced, then, the engineering mathematical model of PV cells is introduced. The perturbation and observation algorithm is chosen as the maximum power point tracking (MPPT) algorithm. The SPWM double-loop control strategy with outer voltage loop and inner current loop is described and a three-phase grid-connected photovoltaic model is established. The simulation results demonstrate the validity and correctness of the simulation model built in this paper.

In this study, the flame-retardant PAN fiber with good moisture absorption, good mechanical properties and better thermal properties has been prepared by blending solution of sodium hydroxide and hydrazine hydrate. FTIR spectra presented that new amide and cyclization-crosslinked pyridine group band peaks appeared. X-ray diffraction showed that the the crystal structure of PAN fibers has been converted from quasicrystalline structure into partially crystallized structure after modification treatment. SEM micrographs indicated that the original longitudinal surface microgroove has changed to layered structure by surfical etchant.

The surface of kevlar fiber was modified by phosphoric acid solutions (H3PO4) in this article. The structure and morphology of the modified fiber were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). The results showed that some polar groups were introduced into the molecular structure of aramid fibers. The interfacial properties of aramid fiber/epoxy composites were investigated by the single fiber pull-out test (SFP). The results showed that the interfacial shear strength (IFSS) of aramid/epoxy composites was remarkbly improved after surface modification and the breaking strength has not been affected appreciably. It provided an efficient method to make the surface modified Kevlar fiber for the application for the advanced composites at a lower production cost.

In this article, a new process was used to make flame resistant polyacrylonitrile (PAN) fibers by surface modification. The effects of the treating conditions during the copper ion treatment, aqueous mixture of hydrazine hydrate treatment and high temperature treatment on the mechanical properties and flammability of the resultant flame resistant fibers were studied. The results showed that the optimum reactiong conditions were: the addition of hydrazine hydrate 20mL, drying time 3min, heating temperature 160°C and heating time 180min.Under these conditions, the flame-retardant PAN fiber with good mechanical properties could be obtained.

Surface modification of Poly(ρ-phenylene terephthalamide) (PPTA) fiber has been considered an effcient way to increase the interfical bonding of the fiber/epoxy composites. In this article, the hydrogen peroxide solutions (H2O2) was used to treat the PPTA fiber based on an orthogonal experimental design. The optimum conditions of H2O2 treatment were concentration of 40%, treating temperature 40°C and treating time 60min. The morphology of the modified fiber were characterized by scanning electron microscope (SEM). The interfacial properties of aramid fiber/epoxy composites were investigated by the single fiber pull-out test (SFP. The results showed that the interfacial shear strength (IFSS) of aramid/epoxy composites was remarkbly improved which was attributed to the fact that some polar groups were introduced into the molecular structure of aramid fibers and the physical structure of the treated fibers was not etched obviously.

Drilling technology of ultra-deep well is still the focal point of drilling research, there are many difficulties in ultra-deep well drilling, such as bottom hole with high temperature and high pressure, complex geology, borehole with sharp dogleg, etc. These technical difficulties put forward higher request in casing running, well quality must be controlled strictly in order to run larger diameter combination casing string successfully. Well quality is closely linked with the drifting drilling assembly design. The accurate stiffness ratio calculation is the key prerequisite of drifting drilling assembly design. In this paper, a new mechanical model is applied to simulate deflection of the drifting drilling assembly. The solution of variable cross-section beam’s equivalent stiffness is applied to solve the stiffness of the drifting drilling assembly. Modified stiffness ratio calculation method for drifting drilling assembly and casing string is proposed. In the process of calculation formula derivation, the conservation of energy law has been used multiple times. At last, the VB computer program is compiled, which contains the modified calculation method. The computer program calculation value is larger than the conventional method’s calculation value. Modified calculation method is more reasonable, which has important significance for drifting drilling assembly optimal design.

For the wide applications and quality problem of silicore plastic duct, by means of analysis of product quality, such as thin wall, small inner diameter, thin silicon core, and considering the requirement of production technology, weighing method and standard interval method is proposed to supervise and inspect procuct quality during production. The purpose of controlling product quality can be achieved, and then project quality and life will be ensured.

After a series of chemical procedures of surface hydrolysis, acidchloride reaction and grafting, Polyacrylonitrile (PAN) fiber was grafted from soybean milk and the soy protein-modified PAN fiber was obtained. The structures and morphologies of the grafted fiber were characterized by Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD) and scanning electron microscope (SEM).The results show that the surface of PAN fiber was covered by soy protein overlay film. Moisture absorption and mechanical properties were investigated. The grafted PAN fiber presented better hygroscopicity and still meet the requirement for wearing.

It is a hazard to human health that urban atmospheric dustfall has increased year by year. The winter atmospheric dustfall in Linyi was studied in the paper, atmospheric dustfall carrying out heavy metal was determined by ICP-AES, and the sources of metal elements in the atmospheric dustfall was analyzed by enrichment factor method. The results showed that Cd, Zn, Cu, Pb and Hg elements in the atmospheric dustfall were significantly affected by man-made factors, and that As, Cr, Mn elements in the atmospheric dustfall were mainly derived from the crust. Meanwhile the results the sources of Zn, Cu, Pb and Hg in dustfall is closely related to coal and oil combustions, but that Cd elements in dust were deeply affected by soil

Based on the view of technical economics, improve on the agricultural value-added model through the introduction of new variables; format the value-added model of coal chemical products. Then take the development of coal chemical industry chain of Yulin City in Shaanxi Province for example, educe the necessity to upgrade its industrial chain. In addition, discuss the strategy to promote coal chemical industry chain from the perspective of strengthening the building of coal chemical industry chain and improving value-added.