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To explore the mechanism of extraction and enrichment of three nitrophenol isomers by charge-transfer supramolecular synergistic three-phase microextraction system, a charge transfer supramolecular-mediated hollow fiber liquid-phase microextraction (CTSM-HF-LPME) combined with high-performance liquid chromatography-ultraviolet detector (HPLC-UV) method was established for the determination of real environmental water samples. In this study, the three nitrophenols (NPs) formed charge-transfer supramolecules with electron-rich hollow fibers, which promoted the transport of NPs in the three-phase extraction system and greatly increased the EFs of NPs. The relationships between the EFs of NPs and their solubility, pK

A novel solvent terminated microextraction method based on a natural deep eutectic solvent (L-menthol and lactic acid at a molar ratio of 1:2) coupled with high-performance liquid chromatography was proposed, which was utilized for the separation and enrichment of bisdemethoxycurcumin, demethoxycurcumin and curcumin in Curcumae Longae Rhizoma and turmeric tea. The effects of independent parameters on extraction efficiency were optimized by single-factor analysis. Subsequently, four predominated parameters affecting the extraction procedure, including extractant volume, salt concentration, demulsifier consumption, and demulsification time, were further evaluated by a central composite design. Under the optimized conditions, the linear ranges of calibration curves were 0.005-0.5 μg/mL for bisdemethoxycurcumin, 0.004-0.4 μg/mL for demethoxycurcumin, and 0.0045-0.45 μg/mL for curcumin, respectively. In addition, the developed method provided low detection limits (0.1-0.4 ng/mL) and high enrichment factors (279-350). Its intra-day and inter-day precision were carried out by relative standard deviation ranging from 2.2 to 9.2%. Finally, the applicability of this method was assessed by the analysis of Curcumae Longae Rhizoma and turmeric tea samples. The results showed that these samples were detected successfully and the spiked recoveries over the range of 85.3-108.9% with relative standard deviations of 1.6-8.9% were attained, indicating its high relative recoveries with good precision in real sample analysis.

Solid-state photon-enhanced thermionic emission (PETE) solar energy converters are newly proposed devices that can directly convert solar energy into electrical power at high temperatures. An analytical model based on a one-dimensional steady-state equation is developed to analyze the temperature-dependent performance of the solid-state PETE converter. The treatment used to derive the reverse saturation current density ( J 0 ) and open-circuit voltage ( V o c ) of the solid-state PETE converter is similar to that used in photovoltaic cells. Thus, their performances at elevated temperatures can be compared. Analysis results show that J 0 of the solid-state PETE converter with a GaAs absorption layer is approximately three orders of magnitude lower, and the decrease rate of open-circuit voltage ( &minus, d V o c / d T ) is smaller than that of a practical GaAs photovoltaic cell. The improved performance of the solid-state PETE converter at high temperatures is attributed to the simultaneous use of diffusion and ballistic transport to harvest photo-generated electrons. The results presented in this paper demonstrate that, besides using wide bandgap materials and increasing doping density, harvesting solar energy via PETE effect can effectively improve the performance of solar cells at elevated temperatures.

In the field of soil stabilization, only calcium silicate hydrate (CSH) and ettringite (AFt) as hydration products have been reported to directly contribute to the strength enhancement of the soil. A chloride dredger fill, an artificial chloride saline soil, and a non-saline soil were stabilized by Portland cement (PC) and PC with Ca(OH)2 (CH) with different contents. A series of unconfined compressive strength (UCS) tests of stabilized soil specimen after curing for 7 d and 28 d were carried out, and the hydration products and microstructure of the specimens were observed by X-ray diffractometry (XRD), scanning electronic microscopy (SEM), and energy-dispersive X-ray analysis (EDXA). The results showed that the strengths of PC+CH-stabilized chloride saline soils were much higher than those of PC-stabilized soils. A new hydration product of calcium aluminate chloride hydrate, also known as Friedel’s salt, appeared in the PC+CH-stabilized chloride saline soils. The solid-phase volume of Friedel’s salt expanded during the formation of the hydrate; this volume filled the pores in the stabilized soil. This pore-filling effect was the most important contribution to the significantly enhanced strength of the PC+CH-stabilized chloride saline soils. On the basis of this understanding, a new optimized stabilizer was designed according to the concept that the chloride in saline soil could be utilized as a component of the stabilizer. The strength of the chloride saline soils stabilized by the optimized stabilizer was even further increased compared with that of the PC+CH-stabilized soils.

Based on three different kinds of conductive paths in microstructure of soil and theory of electrochemical impedance spectroscopy (EIS), an integrated equivalent circuit model and impedance formula for soils were proposed, which contain 6 meaningful resistance and reactance parameters. Considering the conductive properties of soils and dispersion effects, mathematical equations for impedance under various circuit models were deduced and studied. The mathematical expression presents two semicircles for theoretical EIS Nyquist spectrum, in which the center of one semicircle is degraded to simply the equivalent model. Based on the measured parameters of EIS Nyquist spectrum, meaningful soil parameters can easily be determined. Additionally, EIS was used to investigate the soil properties with different water contents along with the mathematical relationships and mechanism between the physical parameters and water content. Magnitude of the impedance decreases with the increase of testing frequency and water content for Bode graphs. The proposed model would help us to better understand the soil microstructure and properties and offer more reasonable explanations for EIS spectra.

In order to simulate and study the mechanism of cement stabilized soils polluted by different contents of magnesium sulfate (MS), a series of tests were conducted on the cemented soil samples, including unconfined compression strength (UCS) tests of blocks, X-ray diffraction (XRD) phase analysis of powder samples, microstructure by scanning electronic microscopy (SEM), element composition by energy dispersive spectrometry (EDS), and pore distribution analysis by Image Processed Plus 6.0 (IPP 6.0) software. The UCS test results show that UCS of cemented soils reaches the peak value when the MS content is 4.5 g/kg. While, the UCS for Sample MS4 having the MS content of 18.0 g/kg is the lowest among all tested samples. Based on the EDS analysis results, Sample MS4 has the greater contents for the three elements, oxygen (O), magnesium (Mg) and sulfur (S), than Sample MS1. From the XRD phase analysis, C-A-S-H (3CaO·Al2O3·3CaSO4·32H2O and 3CaO·Al2O3·CaSO4·18H2O), M-A-H (MgO·Al2O3·H2O), M-S-H (MgO·SiO2·H2O), Mg(OH)2 and CaSO4 phase diffraction peaks are obviously intense due to the chemical action associated with the MS. The pore distribution analysis shows that the hydrated products change the distribution of cemented soil pores and the pores with average diameter (AD) of 2–50 μm play a key role in terms of the whole structure of cemented soil. The microscopic structure of the cemented soil with MS exhibits the intertwined and embedded characteristics between the cement and granular soils from the SEM images of cemented soils. The microstructure analysis shows that the magnesium sulfate acts as the additive, which is beneficial to the soil strength when the MS content is low (i.e., Sample MS2). However, higher MS amount involving a chemical action makes samples crystallize and expand, which is adverse to the UCS of cemented soils (i.e., Sample MS4).

To determine the therapeutic effect and protective mechanism of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) on newborn rats with hypoxia ischemic brain damage (HIBD).Umbilical cord (3-4 cm) was collected from a healthy male infant for preparation of hUC-MSCs using explants technique. The hUC-MSCs were cultured and labeled with BrdU. The differentiation function of MSCs was identified. Healthy SPF grade neonatal SD rats were randomly divided into sham (Rats in the hUC-MSCs treatment group had significant higher weight gain and lower Longa scores (at the second and the third week post transplantation) than those in the HIBD group (Transplanted hUC-MSCs can migrate brain damages through differentiating into neuron-like cells and promoting endogenous neurological differentiations.

A novel microporous membrane/solvent microextraction (MPMSME) approach was developed in which a piece of microporous filter membrane was used as not only extraction solvent holder but also solid phase extraction unit. Subsequently, high-performance liquid chromatography with an UV detector was conducted. The wide exchange surface and very little organic solvent consumption made this sample pretreatment technology very interesting. The cinnamic acid derivatives were used as model analytes to evaluate the procedure. Parameters that affect the MPMSME such as type of extraction solvent, membrane area (or volumes of extraction solvent), aqueous phase pH, ionic strength, extraction stirring rate, extraction time, and sample volume were investigated and optimized. The enrichment factor (EF) of analyte was defined in MPMSME. Under the optimized conditions, the EFs of cinnamic acid derivatives were 43–144. Good linearities were obtained from 4 to 4,000 ng mL−1 for all the analytes with regression coefficients of between 0.9956 and 0.9977; the limits of quantification were below 0.4 ng mL−1, and satisfactory recoveries (93–106 %) and precisions (0.37–13 %) were also achieved. The experimental results showed that the method was simple, rapid, practical, and effective for preconcentration and determination of the cinnamic acid derivatives in rhizoma typhonii.

A novel technique, ionic liquid-water-organic solvent three phase microextraction (ILWOS-3p-ME) was developed and introduced for simultaneous preconcentration and determination of flavonoids and anthraquinones in Chinese herbal formula and its preparations. This technique was performed in one step by using a syringe. High performance liquid chromatography with an UV-detector (HPLC/UV) was subsequently conducted. Two solvents with different densities (organic solvent and ionic liquid with densities less than and higher than water, respectively) were separately placed in a syringe, which was used as an extraction device. A cloudy emulsion was formed by manually shaking the syringe. The mixture was allowed to stand for several minutes; afterward, the emulsion readily separated into three phases: an upper organic solvent extraction phase; a middle aqueous sample phase; and a lower ionic liquid extraction phase. Both the upper and lower layers were transferred to a small Eppendorf (EP) tube. Conducting ILWOS-3P-ME with HPLC/UV, we simultaneously determined the bioactive components of flavonoids and anthraquinones in traditional Chinese medicine. ILWOS-3P-ME is a simple, rapid, practical, and effective method to extract and preconcentrate of different types of trace bioactive components from traditional Chinese medicine simultaneously.

The abuse and uncontrolled discharge of kanamycin may result in potential risks to human health through food chain or environmental residues. Hence, the determination of kanamycin in various matrices is necessary. A sensitive and simple dispersive liquid–liquid microextraction based on solidification of floating organic droplet (DLLME-SFO) method has been developed for monitoring kanamycin in environmental samples. The method of DLLME-SFO after derivatization is coupled with high performance LC with fluorescence detection. The comparison was carried out between the staged and one-step procedure. The results indicated that the fluorescence derivatization reaction with 9-fluorenylmethyl chloroformate should be performed prior to extraction. The derivatization and DLLME-SFO conditions were optimized, respectively. Under the optimal conditions, the proposed method presented good linearity with square correlation coefficient of 0.9934, good reproducibility with relative standard deviations less than 9.6%, and the recoveries of kanamycin ranged from 91.3 to 102.7% for wastewater, and from 90.3 to 107.7% for soil. Furthermore, the detection limit was observed as 0.012 ng/mL. The proposed method was successfully applied to determine low levels of kanamycin in wastewater and soil samples.

Herzog and de Meuron were 2001 Pulitzer prize winners. Their buildings are famous because of the unique and amazing epidermis. In their representative works, there are two major ways to create and form epidermis. The first one is learning from the surrounding context and environment, and the second is thinking about the features of architectures. This paper, through the investigation of six of their major works: Dominus Winery in California of the US(1998), De Young Museum in San Francisco (2004), the library of Brandenburg Industrial University in Germany, the Tokyo Prada flagship store in Japan, Munich Allianz Stadium in Germany, and Laban Centre for Contemporary Dance in London, summarizes the main methods of H&dM.Architecture surface processing is becoming more and more concerned by the construction industry and the viewers. H&dMs methods of design provide our use for reference. Let us look forward to their next new work.

Geobelt, made of polymeric materials, is one of the reinforcement materials. In the present study, a large site loading test program was performed on a square footing supported by the geobelt-reinforced crushed stone layer on the soft soil. The reinforced soil layer is thin, in which the ratio of the reinforced soil layer depth and the footing width is only 0.2. The various parameters studied in this testing program include the number of geobelt layers, the depth of first geobelt layer beneath the footing, the vertical spacing between two geobelt layers, and the linear density of reinforcement. The results show that the performance of the geobelt-reinforced crushed stone cushion was obviously improved compared with unreinforced crushed stone cushion. For one layer of geobelt reinforcement, the effect of the geobelt reinforcement is mainly controlled by the depth of first geobelt layer beneath the footing and linear density of reinforcement. With a shallow depth of the geobelt layer of reinforcement, it works efficiently at a small settlement of the footing. The beneficial effect of a double layer of geobelt is greater than that of a single layer, especially when the settlements are concerned.

GEO-groove simulation experiment is applied to imitate the Taiyuan soil subsidence in pipeline base and side by soil loss, which eventually leads the pipeline to be deformed and destroyed. The pre-damage standard is set up though analyzing test statistics and drawing it’s sedimentation and damage curve. The damage standard of sewage line is achieved through setting up a very pilot model to the test and analyzing it’s bearing force characteristics, and according to the gotten sedimentation curve of the test, damage characteristics and mechanism of sewage line is analyzed , thus will give the designing and application of pipeline of testing and theory basement, so as to take measures to protect pipeline in practical situations, establish early warning system to pipeline, and guarantee it’s regular service.

Currently it is still a lack of reliable evidences on the evaluation of the bearing capacity of foundation in highway construction of Shanxi Province. Mainly reason is that the method widely used to determine in bearing capacity of loess foundation in building structures is not completely suitable to length and wide range of highway subgrade project. Because Shanxi loess region terrain is very complex, the capacity of Q3 loess-like silt in Yuncheng of Shanxi is collected and analyzed, based on statistics of a large number of bearing capacity from site loading tect. A linear regression relationship is established between loess foundation bearing capacities and water content, liquid limit, void ratio. Another linear regression relationship is established between saturation and liquid limit void ratio . Meanwhile, it compares these two sets of linear regression relationship with the measured bearing capacity and the carrying capacity by specification. Applied result show that the relative errors of the bearing capacities computed by the formulas are less than 10%, compared with other standard methods to determine the loess bearing capacity. It is significantly improvement for meeting the requirements of the highway construction.

Through the model test in soil slot,the process of deformation and destruction of soft pipeline caused by subsoil settlement is simulated and observed in lab. Based on the experimental data, the curve as the internal force of pipeline is first drawn out and discussed, in turn the characteristic of stress distribution and destruction rule of pipeline are analyzed and summarized, which may be referred for designer to take appropriate measures. The experimental results show that the internal force and deflection of the pipeline increase with the depth and width of the hole below the pipeline. When the hole depth (h)/ pipeline diameter (D) =2.5, internal force and deflection changes only associate with the width of the hole (b). And when b/D =6, the pipeline can not work normally and even be destroyed. The experimental conclusion can provide the basis for the security of underground pipeline.

The subject of Foundation Excavation near the buried pipeline line. Compared with each other using a scale model of the buried pipeline foundation excavation factor of the vertical displacement, and connected with the buried pipeline displacement of both ends of the fixed elastic beam theory; analysis of the factors affecting the displacement of buried pipelines, the good agreement of the theoretical results with the scale model test value.

A series of compression tests were conducted on the samples taken from compacted soil site in Lulling, in order to investigate the compressibility of compacted loess in different water content and different compaction energy. Through statistics analysis of the testing data, the stress-strain curve of compacted loess could be expressed with Hyperbolic form. And the relation between initial tangent modulus and water content change coefficient was founded by introducing the water content change coefficient. The result shows that at the same compaction energy, the initial tangent modulus decreases and the ultimate strain increases as water content increases; while at the same water content change coefficient, the initial tangent modulus increases and the ultimate strain decreases as compaction effort increases.

An advantageous method based on hollow fiber liposome microscreening (HFLMS) combined with high-performance liquid chromatography (HPLC) has been developed and used in preliminary screening and analysis of biomembrane permeable compounds from herbal medicines (HMs). In the method, a liposome hollow fiber was prepared as a screening tool; permeable compounds that could specifically bind to liposomes were screened from herbal extract to liposome in the pores and lumen of hollow fiber, then permeable compounds were dissociated from liposomes and analyzed by HPLC. The chromatographic separation was applied with a Zorbax Eclipse XDB-C18 column by a gradient elution using acetonitrile, methanol, and phosphoric acid aqueous solution as the mobile phases. In the study, influencing factors of the screened target compounds were investigated and optimized. Under optimum conditions, the surface properties of liposome hollow fibers were characterized, the nonspecific binding between the active center of hollow fiber and the bioactive components were investigated, the repeatability of this method was tested. And eight permeable compounds of flavonoids and anthraquinones from HMs were preliminarily screened and analyzed by HFLMS-HPLC. The results demonstrated that new method is a simple, fast, effective, and reliable method for preliminary screening and analyzing biomembrane permeable ingredients in HMs, and it can be used in screening other permeable compounds in HMs.

This paper studies the microstructure of 16 group samples from three different sites of North-west region in P. R. China. Pictures of microstructure were processed with imaging processing program to acquire the geometer parameter and fractal dimension of pores. The range of pores’ fractal dimension is between 1.816~1.936. The pore distribution function of unsaturated soil is established based on fractal geometry theory. The pore water distribution of loess under natural moisture is analyzed. The relationships of collapsibility coefficient with fractal dimension and porosity of unsaturated pores are analyzed with the method of regression analysis. A larger fractal dimension represents a more complex pore-structure. The collapsibility coefficient of loess increases with the increase of fractal dimension and porosity of unsaturated pores.

The degree of compaction is usually used as the compaction quality and control indicator of backfill in practical project. However, as the degree of compaction is affected by various internal and external factors, its accuracy is difficult to guarantee. In this paper, compacted loess samples were prepared under different compaction energies by normal compaction method. The curves of compression coefficient and dry density, the compression coefficient and porosity of compaction loess samples under different compaction energy are analyzed while the water content is constant. The air porosities of compaction loess samples under different compaction energy and water content are calculated and summed up. The air porosity of compaction loess samples under different compaction energy is more stable than the degree of compaction when the water content is exactly equal to the optimum water content. The rationality of using air porosity as the loess compaction quality control indicator is discussed. It is proposed using air porosity as additional indicator of compaction quality control on the condition of the loess compacted dry density meeting the requirements. The air porosity less than 6.5% is suggested as the additional quality control indictor for region backfill compaction.

To explore the possible mechanism of berberine improve insulin resistance in skeletal muscle of obese rats.Forty Wistar rats were divided into normal control group (NC group, n =10) and high fat food group (HF group, n=30). After the obese model rats established successfully, the rats of NC group (n=10) and HF group (n=10) were sacrificed. The level of fasting plasma endotoxin (ET) was detected. The expression of Toll-like receptor 4 (TLR4) mRNA in skeletal muscle were detected by real time quantitative PCR. The expression of TLR4, IkappaB kinase beta (IKKbeta), phospho-IKKbeta(Ser181) (p-IKKbeta(Ser181)), nuclear factor-kappaB (NF-kappaB), tumor necrosis factor-alpha (TNF-alpha), insulin receptor (IR), insulin receptor substrate-1 (IRS-1), phospho-IRS-1(Ser307) (p-IRS-1(ser307)) and the tyrosine phosphorylation of IR and IRS-1 (p-IR(Tyr) and p-IRS-1(Tyr)) protein in skeletal muscle were detected by Western blot. The twenty HF group rats were randomly divided into two group: the fat model control group (FC group, n=10) were fed with high fat diet and distilled water. The fat berberine group (FB group, n=10) were fed with high fat diet and berberine. All rats were sacrificed after effective interventions of eight weeks. The same indexes as the first part of experiment were detected. Results The results showed that the level of ET was increased. The TLR4/IKKneta/NF-kappaB signaling pathway is activated and the expression of TNF-alpha was increased of the skeletal muscle in obese rats. However, the insulin signaling pathways of the skeletal muscle in obese rats was inhibited. Berberine could reduce the level of ET of obese rats, down-regulate the TLR4/IKKbeta/NF- kappaB inflammation signaling pathway and improve insulin resistance of skeletal muscle in obese rats.Our study revealed that berberine could reduce the level of ET of obese rats, down-regulate the TLR4/IKKbeta/NF-kappaB inflammation signaling pathway in skeletal muscle and berberine can improve insulin resistance of skeletal muscle through inhibiting the active of the TLR4/IKKbeta/NF-kappaB signaling pathway.

To investigate the role of phosphatidylinositol 3 kinase/protein kinase B (PI3K/Akt) signaling pathway for umbilical cord-derived mesenchymal stem cells (UC-MSCs) treating in neonatal rats with hypoxia-ischemia brain damage (HIBD).P10 SD rats were divided into sham group, MSCs group, inhibitor (LY 294002) group (LY group) and HIBD group randomly. To establish a neonatal rat model of HIBD, UC-MSCs labeled with Brd U were transplanted into the lateral ventricle of rats. At 24 and 48 h after transplantation, the number of apoptotic cells was detected by TUNEL, while the expression of caspase3 protein and phosphorylation of Akt (P-Akt) were quantified by Western blot.At 24 and 48 h after transplantation, both the apoptotic cells and caspase3 protein expression in MSCs group were less than those in LY group and HIBD group (P0. 05), while the expression of P-Akt was higher than those in LY group and HIBD group (P0.05), and with the passage of time after transplantation, the expression of each index showed a downward trend.The apoptotic cells of brain and the expression of caspase3 protein decrease, while the expression of P-Akt increase. PI3K/Akt signaling pathway may be an important mechanism for UC-MSCs transplantation in HIBD rats.

In this paper, two methods, organic solvent dispersive liquid–liquid microextraction (OS-DLLME) and ionic liquid dispersive liquid–liquid microextraction (IL-DLLME), coupled with high-performance liquid chromatography have been critically compared and introduced for the analysis of the eight coumarin compounds (psoralen, isopsoralen, bergapten, isobergapten, oxypeucedanin, imperatorin, osthole, and isoimperatorin) in Radix Angelicae Dahuricae samples. Experimental conditions have been investigated for both OS-DLLME and IL-DLLME. Under optimal conditions, the detection limits of the eight coumarin compounds obtained by OS-DLLME and IL-DLLME ranged between 0.002–0.026 ng mL−1 and 0.013–0.66 ng mL−1, respectively. The relative standard deviations (RSDs, n = 9) were lower than 8.7 and 8.4% with enrichment factors in the range of 145–380 and 130–230 folds for OS-DLLME and IL-DLLME, respectively. The results showed that there were no significant deviations between the two DLLME methods for the determination of the eight coumarin compounds. Both methods were simple, fast, efficient, and inexpensive. However, compared with IL-DLLME, the OS-DLLME technique exhibited a higher extraction capacity for the eight target analytes.

Contamination can change the physical properties of soil, reduce the strength of cemented soil foundation, and then induce the instability or disruption of buildings. This study explored the relationships among the age, electrical resistivity, unconfined compression strength, contamination of municipal sewage concentration. Firstly, we mixed the silty clay with municipal sewage of five different concentrations to form the contaminated soil. Then, mixed the contaminated soil with ordinary portland cement to form the cemented soil blocks. Finally, measured the unconfined compression strength and electrical resistivity of these blocks. The results show that the unconfined compression strength and electrical resistivity increase linearly with the increase of the logarithm of age, and decrease exponentially with the increase of municipal sewage concentration. The unconfined compression strength of cemented soil has a linear relationship with its resistivity. The municipal sewage concentration and age can be use to predict the unconfined compression strength of cemented soil.The predicted values correlate well with the experimental values.

With the Drucker-Prager yield criterion, the ANSYS software is used to analyze the long-short-pile composite foundation by using three-dimensional nonlinear finite element method. The influences of load on axial stress and maximal axial stress of head of pile with cushion or not have been investigated by simulating composite foundation through nine long piles and sixteen short piles. The result indicates the cushion can reduce the stress concentration in head of pile effectively with increase of load. This conclusion has a certain value for engineering.

Hollow fiber liquid–liquid phase microextraction followed by high-performance liquid chromatography was employed to research the binding of four furocoumarin compounds (psoralen, oxypeucedanin, imperatorin and isoimperatorin) to bovine serum albumin. The results reveal that the percent of drug–protein binding did not rely on the furocoumarins and protein concentrations, and four furocoumarins scarcely competed for protein binding sites. The protein-binding percents of psoralen, oxypeucedanin, imperatorin and isoimperatorin were 55.1 ± 4.5, 14.4 ± 2.4, 44.1 ± 6.7, and 41.3 ± 3.8%, respectively, the numbers of binding sites were 1.2, 1.6, 0.6 and 0.3, and the binding constants were 1,801, 212, 937 and 4,025 L mol−1, respectively. The proposed new approach is simple, rapid, and effective for the study of the interaction between protein and furocoumarin compounds which is either individual or coexistent with the similar ones.

As an important and mature technology of researching material properties, ac impedance spectroscopy has successfully applied in many discipline except for soil research. Based on the experiments using TH2828A wide frequency LCR meter (from 50 to 106 Hz), the ac impedance characteristics with different water content of soil had been discussed. The results fully illustrate that the ac impedance is one of the basic property of soil,and the value of ac impedance parameter can be reflected the water content quantitatively. when using the fixed frequency to measure ac impedance of soil, it is most suitable as the frequency equals 104 Hz.The measure method of ac impedance have no effect to physical properties and internal structure of soil.

As a simplify and effective method , electrical resistivity has been used in geotechnical engineering. In lab the experiment simulated that cemented soil had been polluted by industrial sulphuric acid after mixing. On different age time, the variation trend among electrical resistivity of cemented soil and solution, formation factor and solution concentration were studied. The results indicated that both of electrical resistivity and formation factor have close correlations with sulphuric acid solution concentrations and pollution level of cemented soil. This shows that the electrical resistivity method are very sensitive for groundwater and cemented soil after pollution in the engineering site.

The pH value and SO42- concentration in corrosive environment may affect mechanical property of cemented soil inturn to cause some serious damage to structure. The results of tests show that the unconfined compression strength is decreasing with the increase of H2SO4 solution concentration, increasing with the increase of pH value. The pH value is increasing and the SO42- concentration is decreasing with the increase of corrosive time. So it is concluded that compressive strength is closely rated with the pH value, SO42- concentration of corrosive environment and corrosive time. Finally a equation is set up based on the relationship of compressive strength and factors affected, which contain the reduced coefficient of compressive strength, pH value, SO42- concentration and corrosive time. The calculated and measured values are close so that the equation could be used in practical design for reference.

Based on the R.C. frame-bent structure in a large-scale thermal power plant’s main building, a 1/7 scale model has been tested by man-excitaiton to determine its’ dynamic properties. The former three frequencies and vibration modes of the model are obtained, and the dynamic property of the original structure is studied based on model similarity theory. At last, modal analysis of plane model and spatial model of prototype are discussed by using ANSYS FEA software, and the spatial dynamic preperty of the irregular structure is analyzed.

Geogrids, made of polymeric materials, have been used as a construction material for many applications, such as walls, slopes, roads, building foundations, etc. In the past, geogrids were manufactured with apertures in a rectangular or square shape. Recently, geogrids with a triangular aperture shape have been introduced into the market. The new geogrids are manufactured with ribs oriented in three equilateral directions and expected to have a more stable grid structure, which can provide more uniform resistance in all directions. In this study, the numerical software – FLAC was adopted to investigate the responses of geogrids with rectangular and triangular apertures when subjected to a uniaxial tensile load at different directions relative to the orientations of ribs in air. The geogrid ribs were modeled using beam elements jointed rigidly at nodes (i.e., the angle between two adjacent ribs did not change) and subjected to tension in one direction. The numerical results showed that the stress–strain responses of the geogrids were different at different loading directions relative to the orientations of ribs. The effects of aperture shape of geogrid, and elastic modulus and cross-section area of geogrid ribs on the tensile stiffness of the geogrid were also evaluated. The geogrid with triangular apertures had more uniform tensile stiffness and strength distributions than the geogrid with rectangular apertures. An increase of the elastic modulus and cross-section area of the geogrid ribs could increase the stiffness of the geogrid with triangular apertures. The numerical results were verified by experimental data for geogrids with rectangular and triangular apertures.

Cemented soil resistivity is one of its inherent properties which can be used to detect its unconfined compressive strength and polluted state. But the cemented soil resistivity is macroscopic showing of its microstructure conductivity. Its resistivity closely relates with resistivity of various material components, such as soil porosity, cement mixing ratio,etc. So further researching the electrical model of cemented soil is great significance. This paper introduces the existing cemented soil electrical model(Komine model). Then based on the microstructural observation of the SEM images of cemented soil, the problems of Komine model are pointed out. Furthermore a more reasonable microstructure is proposed. The new electrical model of cemented soil is set up on three hypotheses. This new model is composed of parallel structure and series structure. Some soil particles surrounded by the hydration products such as CSH or CASH connect with pore water parallel to form the series structure. The hydration products that continue to harden to form the cemented soil skeleton connect with soil particles and pore water to form the parallel structure. The new electrical model of cemented soil can explain better electrical conductive mechanism of cemented soil materials.

To study the brain protection and the possible mechanism of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) in neonatal rat model of hypoxic-ischemic brain damage (HIBD).Successfully establishing a neonatal rat model of HIBD, hUC-MSCs labeled with BrdU were transplanted into the lateral ventricle 24 hours after HIBD. The number of apoptotic cells and the expression of Caspase-3 were detected by TUNEL and Western blot respectively at 24 and 48 hours after transplantation. The neurological functions of HIBD rats were evaluated by Longa score, and the survival, differentiation and pro-differentiation effects of hUC-MSCs were identified by immunofluorescence at 1 to 3 weeks after transplantation.At 24 and 48 hours after transplantation, apoptotic cells and Caspase-3 expression in the MSCs group were less than in the HIBD group (P0.05). At 2 and 3 weeks after transplantation, the Longa score in the MSCs group was lower than in the HIBD group (P0.05). After transplantation, positive cells labeled with BrdU were seen in the brain tissue. The expression levels of glial fibrillary acidic protein (GFAP) and neuron specific esterase (NSE) in the MSCs group were higher than in the HIBD and sham-operated control groups (P0.05), and increased gradually with the transplantation time (P0.05).hUC-MSCs transplantation in HIBD rats can inhibit Caspase-3 expression and reduce apoptotic cells in the early stage, and in the later period, the survival hUC-MSCs can differentiate into neural-like cells and promote the differentiation of endogenous neural-like cells, providing protective effects to brain.

A novel hollow fiber cell fishing with high performance liquid chromatography (HFCF-HPLC) was extended and used to screen flavonoid and anthraquinone active compound groups simultaneously from traditional Chinese medicines (TCMs). In this study, three cells (MCF-7, SGC7901, and MADB-106) were seeded on the inner wall of the hollow fiber employed to screen bioactive components from TCM water decoction. The variables influencing HFCFHPLC, such as cell seeding time, screening stirring rate and time, and active compound concentration, were investigated and optimized. The surface property of the hollow fiber seeded with cells, the cell survival rate under different conditions, the nonspecific binding between active centers in the fiber and the target compounds, and the repeatability and recovery of HFCF-HPLC were analyzed and validated. Certain structures of the compounds fished by HFCF-HPLC were identified after comparing the retention times of the reference substances. To verify preliminarily the binding site between the bioactive components and cells, we separated the cell membrane and cell organelle from live MCF-7 cells. We then employed the cell membrane, cell organelle, and the whole cells to screen simultaneously the active compounds. The cell fishing factor of the active compound was calculated and discussed as the index of cell-drug binding ability in HFCFHPLC. Tamoxifen as a positive control and indomethacin as a negative control were screened by HFCF-HPLC to verify the method. The results indicate that HFCF-HPLC is an effective and reliable method for the screening and analysis of bioactive components. Moreover, this method can be applied to predict bioactive candidates in TCMs.

The carcinogenic or tumourigenic testing of seven animal kidney cell lines (F-81, CRFK, MDCK, Vero, Vero-2 cell line, MA-104 and BHK-21) established in China, were carried out in more than 700 nude mice for colony formation in soft agar and for agglutination under different density of plant lectins. Tests showed that there were correlation between cell line chromosome number variations and anchorage independence in soft agar, agglutinability under lectins and tumour-forming ability in nude mice. Since testing in vitro was more economical, simpler and faster and thus thought to be more reliable, we recommend measuring agglutinability, followed by anchorage independence or analysis of karyotype as the initial means for monitoring tumourigenicity of animal cell lines in nude mice.

To study the effects of oxytocin antagonists-atosiban on pregnancy outcome after thaw embryo transfer (TET).Between Jul. and Dec. 2012, a total of 120 women undergoing TET in Reproductive Medical Center, General Hospital of Tianjin Medical University were randomly allocated into atosiban and control group. They were all transferred 2 or 3 top quality embryos at phase of 7-8 cells . Patients in atosiban group were administered by intravenous administration of atosiban before 30 minutes of embryo transfer with a total administered dose of 37.5 mg. In the control group, no special treatment was given before embryo transfer. All patients in 2 groups underwent progesterone luteal support regularly after embryo transfer, then the clinical rate of pregnancy, implantation and early abortion was compared.The clinical pregnancy rate per cycle and implantation rate per transfer were 60% (36/60) and 30.0% (48/160) in the atosiban group, which were higher than 42% (25/60) and 20.3% (31/153) in the control group (all P0.05). Early abortion rate was 6% (2/36) in the atosiban group, which was no statistical difference comapring with control group [16% (4/25), P0.05].It was suggested that atosiban treatment before embryo transfer can improve the outcome of pregnancy, and increase clinical pregnancy rate and implantation rate after TET.

Hollow fibre cell fishing with high performance liquid chromatography (HFCF-HPLC) is a newly developed method used to screen and fish bioactive compounds in traditional Chinese medicines (TCMs). In the study, colorectal cancer cell HCT116 was first seeded in a hollow fibre and used for screening and fishing active compounds from TCMs. The surface properties of the hollow fibre seeded with HCT116 cells, the non-specific binding between active centres in the fibre and the target compounds, the cell survival rate under different conditions before and after screening, the repeatability and recovery of HFCF-HPLC were investigated in detail. The cell fishing factor of active compound was defined in HFCF-HPLC. We employed HFCF-HPLC to screen and fish anthraquinones active compounds group from extracts of Polygonum cuspidatum, Cecropia obtusifolia L. and Polygoni multiflori radix praeparata. Some of the anthraquinones structures screened from TCMs were identified by comparing to the retention time of the reference substances confirmed by mass spectrometry. The ability of permeable membrane of anthraquinones screened by HFCF-HPLC was further described. Indomethacin was used as the positive control substance. Results demonstrated that HFCF-HPLC is an effective, stable and reliable method to screen and analyse bioactive compounds. Other bioactive compounds from TCMs could also be screened.

Based on the characteristic of high speed line scanning for CCD in transient spectrum detection, a method of transient spectrum detection with array CCD is presented. The high speed line scanning with array CCD was realized by changing the mode of charge transfer. In order to explore the feasibility of this method, a fast detection system of single point based on linear CCD was designed and fabricated. Seven different LED pulses were measured when the system worked at fast detection mode of single point and normal mode respectively. The results demonstrate that the method of fast detection of single point based on linear CCD is feasible, and the rate of single point detection reaches up to 20 MHz. Thus, in theory, it was proved that transient spectrum detection with array CCD by changing the mode of charge transfer is also feasible.

To study the influence of EmbryoGlue on the implantation of embryo and pregnancy outcome in vitro fertilization (IVF)-embryo transfer (ET).From August 2010 to January 2011, 243 infertile patients in Reproductive Medical Center of Tianjin Medical University General Hospital who underwent IVF or intracytoplasmic sperm injection (ICSI) were divided into two groups, including 129 cases used EmbryoGlue as the embryo transfer medium in experimental group and 114 cases used G-2 as embryo transfer medium in control group. Pregnancy outcome were compared between two groups.(1) The female age, IVF/ICSI constituent ratio, previous failure cycles and infertile factors of patients did not show statistical difference between experimental group and control group (P0.05). (2) The implantation rate of women in experimental group increased significantly compared with the control group [30.4% (85/280) vs. 18.8% (48/255), P0.05]; Clinical pregnancy rate increased significantly compared with the control group [48.8% (63/129) vs.34.2%(39/114), P0.05]; Multiple pregnancy rate increased significantly compared with the control group [34.9% (22/63) vs. 20.5% (8/39), P0.05]; Ectopic pregnancy rate decreased significantly compared with the control group [4.8% (3/63) vs. 17.9% (7/39), P0.05].EmbryoGlue can facilitate embryo implantation in IVF-ET and reduce the occurrence of ectopic pregnancy.

Based on the spectral characteristic of the detonation temperature, the present paper presents a measurement system of transient multi-wavelength pyrometry with the theory of multi-wavelength thermometry. The FPGA was applied as the hardware developing platform and the high-speed linear CCD was utilized. Each module was controlled by FPGA to achieve the process of real-time data acquisition, storage and transmission. Using the multiple regression analysis method, the dynamic spectral waveforms were calculated. The two laser spectral lines, 630 and 532 nm, were used to calibrate the corresponding pixel sequence numbers and the No. 175 and No. 270 were confirmed. In this paper, the halide tungsten light was measured. The results show that the system can sample continuous spectrum signal at several different times; the CCD can stably work with 40 MHz clock and the frame scanning frequency can achieve 73 kHz.

Since geogrids with triangular apertures have a more symmetrical and therefore more stable structure than biaxial geogrids, they are expected to provide more uniform resistance in all directions. Laboratory model tests were performed in this study to evaluate the bearing capacities of triangular aperture geogrid-reinforced bases under static loading. Unreinforced bases and biaxial geogrid-reinforced bases were also tested for comparison purposes. In this study, the influence of aperture shape, location, and number of geogrids on the bearing capacity were investigated. The test results showed that all the reinforced sections performed better, when the geogrid was placed within the depth of 2/3 of the plate diameter, than the unreinforced section. Triangular aperture geogrids had higher capacity to weight ratios than biaxial geogrids.

To investigate the influence of transfer distance from the fundus on clinical pregnancy rate and implantation rate in in vitro fertilization and embryo transfer.A total of 98 patients (108 cycles) undergoing ultrasound-guided embryo transfer were divided into two groups according to the distance between the tip of catheter and the uterine fundus: group A:or = 5 -10 mm, group B:or = 10 -or = 15 mm.Clinical pregnancy rate and implantation rate were significantly higher in group B compared with group A [44 % (23/52) vs 25% (14/56), 24% (28/115) vs 14% (17/121), P0.05]. The multiple pregnancy rate, ectopic rate and miscarriage rate were similar in the two groups (P0.05).The depth of the embryo replacement into the uterine cavity may influence pregnancy rate and implantation rate.

In this paper, a novel hollow fiber/graphene oxide/solvent bar microextraction (HF-GO-SBME) coupled with high-performance liquid chromatography was developed and introduced for simultaneous preconcentration and determination of lipid-soluble active ingredients including dihydrotanshinone I, cryptotanshinone, tanshinone I, and tanshinone IIA, as well as water-soluble salvianolic acid B, danshensu, and protocatechuic aldehyde in Radix Salvia miltiorrhiza. To evaluate the technique, seven compounds of varying polarity were used as model analytes, and a polyvinylidene fluoride hollow fiber of 1.0 cm filled with graphene oxide attached n-octanol was used as a microextraction bar. The extraction conditions, including the amount of graphene oxide, the type and amount of organic solvent, sample phase pH, salt concentration, agitation speed, extraction time, and sample phase volume, were investigated and optimized in detail. The solid–liquid synergistic microextraction mechanism of HF-GO-SBME was analyzed and verified. Under the most favorable conditions, the enrichment factors of the target analytes were 2.4–905, the limits of detection were below 0.92 ng mL−1, and the recoveries were between 84.5% and 107.5%. Thus, HF-GO-SBME is a simple, effective, low-cost, high enhancement factor and practical microextraction mode with a wide range of potential applications for extraction and preconcentration of trace analytes.

The thermal and electrical properties of Herrin No. 6 Illinois Basin bituminous coal have been determined. The thermal conductivity and thermal diffusivity of wet and dry solid coal samples, in which the heat flow is orientated parallel and nonparallel to the bedding planes, have been determined as a function of temperature using the transient-hot-wire and transient-hot-plate methods. The data are fit to polynomials for convenient use. The electrical resistivity has been determined as a function of temperature, applied voltage and moisture content using the ASTM standard method D 257-78 and a special guarded-electrode apparatus. The dielectric breakdown strength has been determined as a function of sample moisture, sample thickness, electrode size, voltage rate-of-rise and temperature using the ASTM standard method D 149-81.