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Thermal expansion coefficients measurements of AgGa 0.7 In 0.3 Se 2 with the direction of c- and a- axis are made in the temperature range between 300 and 900 K. It is obviously that AgGa 0.7 In 0.3 Se 2 is with a reverse thermal expansion behavior along the c -axis, and variation of directional coefficient at different temperatures as a function of cos2φ has been discussed in this work. It’s found that the crystal would expand with increasing temperature if the angle between the direction [ hkl ] and the c-axis is greater than 42.71°. In addition, Gruneisen parameters at different temperatures have been calculated and also exhibit anisotropic behavior ( γ a > γ c ). At last, by a modified formula, variation of lattice thermal conductivity with temperature have been deduced. And the calculation value at room temperature is a little larger than the measurement value of thermal conductivity with [100] direction at room temperature which is found to be 0.751 W/m K.

AgGaGeS

AgGaGe

Exendin-4 has been clinically adopted as an effective drug for treating type 2 diabetes (T2D), but its short circulation half-life in the blood requires two injections per day to maintain effective glycemic control. This significantly limits its clinical application. In this study, we developed a tannic acid/exendin-4/Fe3+ ternary nanoparticle system to provide sustained release of exendin-4 in vivo. The formation of these nanoparticles relies on TA/exendin-4 complexation and stabilization through TA-Fe3+ coordination, where the rapid reaction kinetics can benefit from efficient mixing of all three components. Adapting our recently developed flash nanocomplexation (FNC) method, we formulated nanoparticles with high encapsulation efficiency (~ 100%) of exendin-4, high payload capacity, and high degrees of uniformity and stability because the rapid turbulent mixing facilitated a homogeneous distribution of all three components in the complexation process. Intraperitoneal injection in mice showed that exendin-4 released from the nanoparticles had an AUC 7.2-fold higher than the free exendin-4 injection. Efficacy study in a T2D mouse model showed that the optimized formulation achieved a rapid reduction of the blood glucose level to the normal range within

The contamination of heavy metals (e.g., Hg, Pb, Cd and As) poses great risks to the environment and human health. Rapid and simple detection of heavy metals of considerable toxicity in low concentration levels is an important task in biological and environmental analysis. Among the many convenient detection methods for heavy metals, DNA-inspired gold nanoparticles (DNA-AuNPs) have become a well-established approach, in which assembly/disassembly of AuNPs is used for colorimetric signaling of the recognition event between DNA and target heavy metals at the AuNP interface. This review focuses on the recent efforts of employing DNA to manipulate the interfacial properties of AuNPs, as well as the major advances in the colorimetric detection of heavy metals. Beginning with the introduction of the fundamental aspects of DNA and AuNPs, three main strategies of constructing DNA-AuNPs with DNA binding-responsive interface are discussed, namely, crosslinking, electrostatic interaction and base pair stacking. Then, recent achievements in colorimetric biosensing of heavy metals based on manipulation of the interface of DNA-AuNPs are surveyed and compared. Finally, perspectives on challenges and opportunities for future research in this field are provided.

The optical-phonon spectra of CdGeAs2 were investigated by low temperature polarized Raman scattering. According to vibrational modes of ZnS-type materials and selection rules of Raman scattering, all Raman active vibrational modes in the Brillouin-zone (BZ) center of CdGeAs2 predicted from group-theory arguments were identified and artificially grouped in three energy bands, including 45–94, 158–215 and around 260 cm−1. Based on the Lyddane-Sachs-Teller (LST) relation and measured refractive indices, the low-frequency dielectric constant e(0) is estimated to be 15.04 and shows good agreement with the previous tests and predictions.

Chalcopyrite of CdGeAs 2 single crystal was grown by a modified vertical Bridgman method with sufficient size and quality, and its optical, electrical and thermodynamic properties are characterized. The transmission is recorded in the 2.3–18 μm range, and the band-gap at room temperature is at 0.56 eV. Non-ideal transparency near 5.5 μm which limited its application severely exists in the front of the crystal. The crystal is p type at room temperature with hole concentrations varying from 10 14 to 10 16 cm −3 . From the results of X-ray diffraction measurements carried out over the range 25–450 °C and thermal dilatometer tests, the thermal expansion coefficients are evaluated. And on this basis the Gruneisen parameters at different temperatures are evaluated and also exhibit anisotropic behavior ( γ a > γ c ). It is found that γ a , γ c , and γ V have some difference between these two kinds of test methods. Using these Gruneisen parameters, lattice thermal conductivities have been deduced by two correction formulas. Meanwhile, specific heat capacity and thermal conductivity of [204] have been obtained as a function of temperature by experiment.

A high-quality ZnGeP2 (ZGP) single crystal with large size of Φ30 mm × 80 mm was grown by a modified vertical Bridgman method. ZGP wafers were annealed with ZGP polycrystalline powder for 300 h at 550, 600 and 650 °C, respectively. The as-grown and annealed crystals were characterized by X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FTIR), IR microscope and energy-dispersive spectroscopy (EDS). Results show that the quality of all wafers is improved evidently after annealing and the optimum annealing temperature obtained is 600 °C. The IR transmittance of the wafer measured by FTIR is up to 56.78 % at wavelength of 2.0 μm nearby and exceeds 59.00 % in the wavelength range of 3.0–8.0 μm. The deviations from stoichiometry decrease, and the homogeneity of the crystal is also improved after annealing. In this paper, scanning infrared map was proposed as a new nondestructive method to evaluate optical quality and homogeneity of crystal through comparing the IR transmittance with the three-dimensional IR spectral contour map.

As a promising material for second harmonic generation (SHG) and optical parametric oscillator (OPO), CdGeAs 2 single crystals are difficult to reproducibly grow with low loss optical, particularly in the region of 5.5 μm. In addition, a correlation between processing conditions and absorption has attracted various researchers to focus on this problem. This paper describes a series of etching experiments and Hall measurements which were undertaken to see if there might be a relationship between dislocation density, carrier concentration and optical absorption. In this study, a single crystal was grown by the modified Vertical Bridgman method. The spontaneous nucleation growth direction has been determined as [102]. Etch pit densities (EPD) about 10 5 cm −2 were observed at the edges of the boules, whereas etch pits were almost not found in the center. The distribution of dislocation along the radial direction affected optical homogeneity, and the high EPD caused the low transmittance. Meanwhile, the samples are p type at room temperature with hole concentrations varying from 10 14 to 10 16 cm −3 . A linear correlation between absorption at 5.5 μm and hole concentration is established. The results of these experiments are very useful for improving radial and axial optical uniformity of the crystal grown by modified Vertical Bridgman method.

Large and heavily Ho 3+ -doped BaY 2 F 8 single crystals were grown by the Czochralski method. X-ray powder diffraction was applied to analyze the phase of the crystal samples. Simultaneously , metallographic microscope, scanning electron microscopy and energy dispersive spectrometer were employed to observe and investigate defects in the as grown crystals. Two significant kinds of defects, namely cracking and impurities were discovered in the samples of Ho 3+ :BaY 2 F 8 single crystals. Theoretical analyses suggested that mechanisms concerning the formation of the impurities such as bubbles and inclusions were considered to be closely related to the growth temperature and atmosphere while the former defect was primarily brought by the lattice distortion relating to the thermal stress and the impurities. Based on the results of experiments and theoretical analyses, the parameters of growth process were optimized and a crack free 20 mol% Ho 3+ :BaY 2 F 8 single crystal has been successfully obtained. Furthermore, the UV–Vis-IR (0.2–10 μm) absorption spectra of BaY 2 F 8 single crystal and the crystal heavily doped with Ho 3+ ions (20 mol%) have been investigated at room temperature.

The characteristic of temperature field plays a significant role in the compaction quality of asphalt pavement, and various factors could affect the thermal parameters of the pavement and thus affect the distribution of the temperature field during compaction. In this research, the temperature transfer theoretical model and finite element model of asphalt pavement were established and calibrated through field measured data, and the sensitivity analysis was conducted to evaluate the factors affecting the temperature field, also a quantitative model of effective compaction time was established. The results found that the initial rolling temperature and layer thickness affected the overall temperature field during compaction, and the wind speed and air temperature mainly affected the temperature field of the upper layer of hot mix asphalt (HMA). The change of the underlying layer temperature mainly affected the temperature field of the bottom of the layer. The established quantitative model provided a mathematic tool for the guidance of the field compaction process.

Ischemia-reperfusion (I/R) is a major cause of acute kidney injury (AKI), which is associated with unacceptably high mortality rates in ICU. This research was designed to explore the therapeutic effect of BAPTA-AM (1,2-Bis(2-aminophenoxy) ethane-N,N,N,N-tetraacetic acid tetrakis(acetoxymethyl ester)) nanoparticle (BA-N) on AKI. BA-N was developed by liposome strategy and characterized by standard methods. The rat model was selected and the rats were randomly allocated into four groups: (1) Normal group; (2) Sham-operated group; (3) Model group (I/R + NS); (4) BA-N treatment group (I/R + BA-N). AKI model was established via clipping the bilateral renal artery with a microvascular clamp for 45 min. After reperfusion, serum cystatin C (Cys C), creatinine (Cr), blood urea nitrogen (BUN), lactate dehydrogenase (LDH) and caspase 3 levels were determined for the assessment of renal function. Kidney samples were then collected for the measurement of renal malondialdehyde (MDA) level and superoxide dismutase (SOD) activity. The assays of histological examination, ELISA, immunohistochemistry, western blot, TUNEL and RT-PCR were utilized for the detection of apoptosis. The results demonstrated that AKI model caused a significant decreasing in SOD activity, accompanied by a remarkable increase in Cys C, Cr, BUN, LDH, MDA, caspase 3 and cytochrome c (Cyt C) level, compared to the control group. BA-N (100 μg/kg i.v.) significantly improved renal function and histopathological appearance, restored MDA level and SOD activity, decreased Bax/Bcl-2 ratio, caspase 3 activity, Cyt C release and TUNEL positive apoptotic cells. Our studies indicated that BA-N plays a renal-protective role, probably through antiapoptotic and antioxidant mechanisms. BA-N may regulate mitochondria pathway via decreasing Bax/Bcl-2 ratio, inhibiting caspase 3 expression and Cyt C release. Overall, BA-N may have potentials as an anti-AKI drug.

This paper studies the optimal operation strategy to minimize the energy consumption of high-speed train running between adjacent stations. The characteristics of high-speed trains, including traction characteristic and regenerative braking, and the railway geographical conditions are fully considered in the dynamic model. Based on discretization analysis of the route, a novel optimal operating strategy consisting of a global optimization process and a further optimization process is developed to reduce the energy consumption. In the global optimization process, genetic algorithm is applied to search the optimal speed at each end of subsection in fixed time. Then, the optimization strategy is further studied to search the speed serial to improve the train operation process. To verify the effectiveness of the proposed operating strategy, the optimization strategy is simulated, and the operation performance of CRH-3 is tested. In comparison to regular train operation strategies, the proposed operation strategy is proved to obtain the favorable results for high-speed trains. And the simulating operation results meet the requirements of time, comfort and energy consumption.

This paper proposes a compact multiple-input-multiple-output (MIMO) antenna with a small size of $31\times 26\times 0.8mm^{3}$ . The antenna consists of two radiation patch fed by microstrip and placed symmetrically. The T-shaped stub stretched from ground is applied to improve the isolation and to broaden the bandwidth. In order to reduce the interference from nearby band, band-notched function of the antenna is required. For achieving triple band-notched characteristics, C-shaped cutting slot and S-shaped slot on the patch are applied to provide the stop-band of WiMAX, WLAN and X-band for satellite communication. Simulation measurement is taken into optimization of the antenna performance, such as reflection coefficients, coupling between two feeding ports and radiation patterns. The results illustrate that the proposed UWB MIMO antenna has an impedance bandwidth of 3GHz-10.5GHz and low mutual coupling less than -20dB, which make it a pleasant candidate for modern UWB MIMO communication system.

Non-small-cell lung cancer (NSCLC) accounts for over 85% of clinical lung cancer cases, which is the leading cause of cancer-related death. To develop new therapeutic strategy for NSCLC, a library of L-phenylalanine-based poly(ester amide) (Phe-PEA) polymers was synthesized and assembled with docetaxel (Dtxl) to form Dtxl-loaded Phe-PEA nanoparticles (NPs). The hydrophobic Phe-PEA polymers were able to form NPs by nanoprecipitation method and the characterization results showed that the screened Dtxl-8P4 NPs have small particle size (∼100 nm) and high Dtxl loading (∼20 wt%). In vitro experiments showed that Dtxl-8P4 NPs were rapidly trafficked into cancer cells, then effectively escaped from lysosomal degradation and achieved significant tumor cell inhibition. In vivo results demonstrated that Dtxl-8P4 NPs with prolonged blood circulation could efficiently deliver Dtxl to A549 tumor sites, leading to reduced cell proliferation, block metastasis, and increase apoptosis, then persistent inhibition of tumor growth. Therefore, Phe-PEA NPs are able to load high amount of hydrophobic drugs and could be a promising therapeutic approach for NSCLC and other cancer treatments.

Background Midazolam has some potential in pain control of patients undergoing knee arthroscopy. However, the results remain controversial. We conduct a systematic review and meta-analysis to explore the effect of midazolam on pain control after knee arthroscopy. Methods PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases are systematically searched. Randomized controlled trials (RCTs) assessing the effect of midazolam on pain management after knee arthroscopy are included. Two investigators have independently searched articles, extracted the data, and assessed the quality of the included studies. This meta-analysis is performed using the random-effect model. Results Six RCTs are included in this meta-analysis. Compared with control intervention after knee arthroscopy, midazolam intervention can significantly reduce the pain scores (standard mean difference (Std. MD) = − 3.70; 95% confidence interval (CI) = − 6.81 to − 0.60; P = 0.02), the number of patients requiring analgesics (risk ratio (RR) = 0.66; 95% CI = 0.49 to 0.88; P = 0.005), and analgesic consumption (Std. MD = −1.62; 95% CI = − 3.04 to − 0.19; P = 0.03), as well as increase the time to first analgesic requirement (Std. MD = 1.58; 95% CI = 0.17 to 2.99; P = 0.03). In addition, midazolam intervention results in no increase in adverse events following knee arthroscopy (RR = 0.74; 95% CI = 0.18 to 2.98; P = 0.67). Conclusions Midazolam intervention is revealed to substantially reduce the pain scores, the number of patients requiring analgesics, and analgesic consumption, as well as improve the time to first analgesic requirement after knee arthroscopy.

PbI2 is a type of syntectic compound, and its single crystal is one of the room temperature semiconductor nuclear radiation detector materials. A new method for the growth of the PbI2 single crystal is proposed in this article, which was named the top seed vertical zone melting method (TSVZMM), directly from the synthesis of polycrystal with analytically pure lead and iodine, by controlling the decomposition and stratification of the melt and the stoichiometry of the PbI2 crystal. Impurities in the crystal and the coagulating droplets of lead were eliminated during the PbI2 crystal growth process from the top to bottom by TSVZMM. The PbI2 single crystal was successfully grown with the size of Φ15 mm×15 mm, an infrared transmittance of more than 40%, a resistivity of 2×1012 Ω cm magnitude and stoichiometry close to its theoretical value.

In present work, thermal properties of silver thiogallate (AgGaS 2 ) crystal were investigated by means of differential scanning calorimetry (DSC) measurements performed at different heating and cooling rates. The DSC results confirmed that the melting point was 1249 K with a slight change around 5 K and that the nucleation temperature varied from 1183 K to 1218 K. The supercooling temperature was evaluated in the range 37.69 K to 62.46 K which was considered to be harmful for the single nucleus formation at the beginning of crystal growth. The activation energy E and the pre-exponential factor A were also calculated using different isoconversional methods, namely Kissinger–Akahira–Sunose (KAS) method and Flynn–Wall–Ozawa (FWO) method, and the results showed good agreement with each other. According to the results of DSC, a larger temperature gradient up to 30 K/cm was utilized to suppress the formation and growth of multi nuclei and a rapid cooling rate 25 K/min was applied to minimize the second-phase precipitates during the process of crystal growth. Finally, an integral and transparent AgGaS 2 single crystal with diameter of 22 mm and the length of 55 mm was obtained.

We performed the first-principles calculations on the elastic and thermal properties for chalcopyrite ZnSnX2 (X = P, As, Sb), employing the ultrasoft pseudo-potentials and generalized gradient approximation (GGA) under the frame of density functional theory. The equilibrium structural lattice constants are in good agreement with reported data. The elastic characteristics were evaluated under high-pressure condition (0–20 GPa), such as the elastic constants, bulk modulus, shear modulus, Poisson’s ratio, Zener anisotropy and compressibility index. Combining with quasi-harmonic Debye model, the thermal properties were confirmed at different temperatures (0–1200 K) and pressures (0–20 GPa), including the heat capacity, thermal expansion, Debye temperature, entropy, and Grüneisen parameter. Based on the semi-empirical relation, the hardness of materials was determined at various temperatures and pressures. Finally, the phonon spectrum curves and vibration frequencies of phonon were evaluated to confirm the thermodynamic stability of ZnSnX2. The Raman scattering spectrum and infrared absorption spectrum were simulated for chalcopyrite ZnSnX2.

By the method of descending crucible with rotation, crack-free CdGeAs2 single crystals of Φ15 mm × 50 mm were grown in a furnace with three independent heating zones after optimizing the temperature field, and the descending and rotational speed to meet the need of CdGeAs2 crystal growth. The properties of as-grown crystal were characterized by a variety of techniques. The results of X-ray diffraction (XRD) show that there are two cleavage faces, which are (110) and (101). The peaks are in high intensity and good symmetry, which demonstrates that the crystal is integral in structure and well crystallized. The energy-dispersive spectrometry results indicate that the wafer of the CdGeAs2 crystal is closer to the stoichiometry. The IR transmittance of the wafer is ~48.6 % at 5.5 μm, and the maximum value is up to 51.6 % in the range of 2.3–18.0 μm. Etch pits of (001) face are observed and the density of the etch pits is evaluated to be 1 × 105 cm−2.

The ground state parameters of interest such as the lattice constants, band structure, bulk modulus and elastic constants are calculated for chalcopyrite CdSiP2 using density functional theory (DFT). Detailed comparisons are made with published experimental and theoretical data and show generally good agreement. Based on the results above, we also presented the thermodynamic properties of CdSiP2 using the quasi-harmonic Debye model, in which the lattice vibrations are taken into account. Finally, we have successfully obtained the variations of the relative volume V/V0, thermal expansion coefficient α, heat capacities C, Debye temperature Θ and Gruneisen parameter γ as a function of the pressure and temperature.

The structural, elastic and thermodynamic properties of chalcopyrite CdGeAs2 were investigated using the pseudopotential plane wave within the local density approximation. The calculated lattice parameters agree well with experimental and previous theoretical works. Based on the elastic constants and their related parameters, the crystal mechanical stability has been discussed. Moreover the pressure and temperature dependences of the lattice parameters, bulk modulus, Debye temperature, Gruneisen parameter, entropy, volume thermal expansion coefficient and specific heat capacities were predicted using the quasi-harmonic Debye model.

A CdSiP 2 single crystal measuring 15 mm in diameter and 35 mm in length was grown by the modified vertical Bridgman method adopting a specially designed double-walled quartz ampoule. The as-grown crystal was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray fluorescence (XRF), infrared (IR) and visible–near infrared (VIS–NIR) spectrophotometers and X-ray photoelectron spectroscopy (XPS). It is found that multiple diffraction peaks of a (101) cleavage face are evident and parallel growth steps on the face are observed. The XRF result indicates that the chemical composition of the as-grown crystal is close to the ideal stoichiometry. The IR transmittance of a sample with 2 mm thickness is about 48% in the range from 10,000 to 1500 cm −1 . The VIS–NIR spectrum shows that the short wave absorption edge is at about 576 nm and the calculated band gap is about 2.15 eV. The binding energies of the Cd 3d 3/2 , Cd 3d 5/2 , Si 3d and P 2p core levels are determined to be 411.8 eV, 405.1 eV, 101.1 eV and 129.5 eV, respectively. These results show that the quality of the as-grown crystal is good and the double-walled quartz ampoule technique is promising for the growth of high-quality CdSiP 2 single crystals.

Background The effects of omega-3 fatty acids (PUFA) on the prevention of atrial fibrillation (AF) appear to contrast between several randomized controlled trials (RCTs). Therefore, we performed a meta-analysis to assess the efficacy and safety of PUFA for the primary and secondary prevention of AF. Methods PubMed, EMBASE, Web of Science, Cochrane Library and the Chinese Biomedical Literature Database were searched for randomized controlled trials (published up to January 2012) that compared PUFA with control. All statistical analyses were performed with RevMan (version 5.1; The Cochrane Collaboration, Oxford, United Kingdom). Results For primary prevention after open heart surgery: 6 studies with 928 patients were designed to evaluate the effects of PUFA on the incidence of postoperative AF. The use of PUFA significantly reduced the incidence of postoperative AF (odds ratio [OR] 0.66; 95% confidence interval [CI], 0.49 to 0.88; P = 0.004); there was no difference in complications or adverse events (OR, 1.24; 95% CI, 0.58-2.62; P = 0.58). For secondary prevention, we analyzed 5 studies involving 1256 patients designed to evaluate the effects of PUFA therapy on AF. The use of PUFA did not significantly reduce the recurrence of AF (OR, 0.74; 95% CI, 0.39-1.42; P = 0.37); no difference was observed in complications or adverse events (OR, 1.10; 95% CI, 0.78-1.57; P = 0.58). Conclusions The meta-analysis shows that PUFA therapy is significantly associated with a decreased odds of incidence of AF after open heart surgery, but there is no significant difference in recurrence of AF between PUFA and control groups. PUFA is well-tolerated, with no difference in complications or adverse events between PUFA and control groups.

A crack-free CdGeAs2 single crystal 15 mm in diameter and 50 mm in length was grown in a three-zone tubular furnace by the modified vertical Bridgman method. During the annealing processes, the effects of treatments with different atmosphere, different temperatures and time were investigated. The as-grown and annealed wafers were characterized using X-ray diffractometer (XRD), energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR) and IR microscope. Conclusively, the results confirm annealing could improve the optical qualities of as-grown CdGeAs2 crystal. The best result was obtained under cover-up with CdGeAs2 polycrystalline powder at 450 °C for 150 h and the IR transmittance of the wafer measured by FTIR was up to 48.65% nearby 5.5 μm and exceeded 50% in the range of 8–12 μm. Additionally, the monolithic homogeneity of the crystal has also been greatly improved after annealing under cover-up with polycrystalline powder.

The causes of non-stoichiometry in both synthesis and growth process of ZnGeP 2 (ZGP) have been studied. The effects of mechanical oscillation (MO) and gradient cooling (GC) techniques employed in the synthesis of ZnGeP 2 polycrystals have been investigated. X-Ray Diffraction analysis (XRD) has identified that phosphorus was the main loss component. The growth of ZnGeP 2 crystal was carried out in a three-section vertical Bridgman (VB) furnace. A certain amount of phosphorus was added to ZnGeP 2 polycrystals before growth. The temperature gradients were controlled at 10–15 °C/cm within crystallization zone. A ZnGeP 2 crystal with the size of Φ 25 mm×55 mm was obtained. The proportions of P, Ge and Zn in the grown crystal were measured with Energy Dispersive Spectrometer (EDS). The results showed that the grown crystal has good stoichiometry and homogeneity. Infrared transmittance and absorption spectra show that the crystal has low absorption in 2.0–10.0 μm range. Absorption contour maps by automatic infrared microscope demonstrate that optical homogeneity of grown crystal is good.

We present an ab initio theoretical study of the electronic, linear and nonlinear optical properties of CdGeAs{sub 2} using a pseudopotential plane-wave method. Specifically, we evaluate the band structure, density of states, charge density, the dielectric function {epsilon}({omega}) and the second harmonic generation response susceptibility {chi}{sub 312}{sup (2)}(-2{omega};{omega},{omega}) over a large frequency range. As LDA underestimates the band gap, we have applied the GW approximation method to calculate the quasiparticle band structure and obtain an energy band gap in agreement with experiment. In this case the opening of the gap due to the GW correction can be used as scissor shift to calculate the linear and nonlinear optical properties. The intra- and inter-band contributions to the imaginary part of {chi}{sub 312}{sup (2)}(-2{omega};{omega},{omega}) are presented over a broad energy range. It is found that the small energy gap semiconductor CdGeAs{sub 2} has larger values of {epsilon}{sub 1}(0) and {chi}{sub 312}{sup (2)}(0) than other chalcopyrite structures. - Graphical abstract: Calculated total imaginary part of {chi}{sub 312}{sup (2)}(-2{omega};{omega},{omega}) spectra along with the intra-(2{omega})/(1{omega}) and inter-(2{omega})/(1{omega}) band contributions. Highlights: Black-Right-Pointing-Pointer We find that the charge density around the cation Cd of CdGeAs{sub 2} is spherical. Black-Right-Pointing-Pointer We do not have to rely on experimentalmore » gap to determine the self-energy. Black-Right-Pointing-Pointer It is the first time we have calculated the SHG susceptibility using pseudopotential plane-wave. Black-Right-Pointing-Pointer The SHG susceptibility beyond zero frequency was calculated.« less

High-purity, single-phase CdSiP2 polycrystalline materials were synthesized directly from the constituent elements by a new method without graphite boat sealed in silica ampoule. The problem of explosions was solved by careful control of the heating and cooling cycle and adopting the two-zone rocking furnace with specially designed temperature profile. Mechanical and temperature oscillations as well as gradient cooling were introduced in the synthesis process. The mechanism and advantages of this new method are discussed. X-ray diffraction (XRD) analysis and Energy dispersive X-ray (EDX) microanalysis both indicated that the synthesized compound is high-quality CdSiP2 polycrystalline material.

A high quality ZnGeP 2 (ZGP) single crystal 22 mm in diameter and 70 mm in length was grown by a modified vertical Bridgman method. The as-grown and annealed crystals were characterized using XRD, IR spectrophotometers, positron annihilation lifetime (PAL), Hall Effect and resistivity measurements. It is found that there was a cleavage face {2 0 4} along the appearance face on the as-grown crystal. After annealing the crystal, the width of XRD rocking curve of the annealed crystal was decreased, the intensity was high and the symmetry was better than that of the as-grown crystal. The IR transmission spectrum indicated that annealing decreases significantly the optical absorption in the region of 1.3–2.6 μm and transmittance exceeds 57% in the range of 3–8 μm. PAL results showed that single zinc vacancies were unstable since they aggregated with each other after annealing under zinc vapor at 500 °C, and both the number of single zinc vacancy and the size of large vacancy decreased under cover-up with ZGP polycrystalline powder at 600 °C. The Hall effect and resistivity measurement results showed that the ZGP crystal has p-type conductivity; after annealing with ZGP polycrystalline powder the carrier concentration was decreased to 10 10 cm −3 and resistivity was increased to 10 8 Ω cm. The above mentioned results demonstrated that annealing treatment improved significantly the optical quality of as-grown ZGP crystal; the proposed annealing process is effective and a promising new method to decrease of the point defects in the ZGP crystal.

Large, integral AgGa 1− x In x Se 2 ( x =0.6, 0.8) single crystals were grown from a melt. The polycrystalline charges were successfully synthesized from high purity elemental starting materials by the vapor transport method with the melt and temperature oscillation. The crystallization processes were carried out in two-layer quartz ampoules with ampoule rotation and the real-time temperature compensation technique. The quality of the as-grown crystals was characterized using a microscope, XRD, IR and vis–NIR spectrophotometers, etc. Cleavage faces of (1 1 2) were found, and high transmittance of the crystals in the mid-near IR region was revealed. The absorption edges of the materials are near 905 and 958 nm, and the calculated band gaps are about 1.37 and 1.29 eV. All the measurements confirmed the good quality of the grown crystals.

A chemical etching orientation method is suggested for the ZnGeP 2 crystals. Several polished faces of ZnGeP 2 crystals were etched in a certain etching solution. Some regular etch pits appeared on all samples. The indices of side facets of the etch pits were measured by X-ray rocking method, which mainly belong to {2 0 4}, {1 1 2} and {1 1 0}. Then the three crystallographic axes of the crystals were determined according to the angle relationship. Finally, optical parametric oscillator (OPO) devices were cut at the direction of θ =0° and φ =53°.

The growth procedures for CdSe crystal have been optimized by thermal analysis techniques and a high-quality single crystal with large size has been grown. CdSe crystal was determined to exhibit smooth interface growth based on Jackson’s model; the growth rate equation in the vapor phase method was built and the thermodynamic parameters (activation energy and rate constant pre-factor) in the growth equation were obtained by thermogravimetic analysis of the sublimation process of the crystal. The growth rate distribution curves under various temperature differences between the source and growth region of growth ampoule were obtained, and then the growth procedures such as temperature difference, growth temperature and pulling rate were optimized. Using the optimizing vapor phase growth technique, a single crystal with 26 mm diameter and 45 mm length has been grown, and it was characterized by X-ray diffraction, scanning electron microscopy, energy dispersive analyzer of X-ray and IR spectrophotometers. The results show that the as-grown CdSe ingot has prefect crystallinity, good homogeneity and high transmittance, which showed that the vapor phase growth technique optimized by thermal analysis was a promising growth method for high-quality CdSe single crystal.

A large, crack-free CdGeAs2 single crystal measuring 15 mm in diameter and 45 mm in length was grown in a vertical three-zone tubular furnace by a modified vertical Bridgman method, i.e. quasi-seed technique with small temperature gradient and descending quartz ampoule. High-purity, single phase CdGeAs2 polycrystallite for crystal growth was synthesized using a rocking furnace with temperature oscillation techniques. Various measuring means, including X-ray diffractometer(XRD), Fourier transform infrared spectroscopy(FTIR), and Field emission scanning electron microscope(FE-SEM) were adopted to characterize the as-grown crystal. It is found that the cleavage plane of the as-grown crystal is {1 0 1} face; the crystal is integrated in structure and crystallized well; etch pits in the shape of pentagon on (1 1 2) face have been observed for the first time using the new preferential etchant we prepared. All these results encouragingly indicate that the modified vertical Bridgman method is a convenient and effective way for high quality CdGeAs2 crystal growth.

Oral delivery of protein drugs is an attractive route of administration due to its convenience for repeated dosing and good patient compliance. However, currently oral protein therapeutics show very low bioavailability mainly due to the existence of hostile gastrointestinal (GI) environments, including mucus layers and intestinal epithelial barriers. Herein, using insulin as a model protein therapeutic, the core-shell nanoparticles with thiolated hyaluronic acid (HA-SH) coating (NPHA-SH ) are produced utilizing a two-step flash nanocomplexation process to enhance oral delivery efficiency of insulin. A positively charged nanoparticle core is first generated by electrostatic complexation between insulin and N-(2-hydroxypropyl)-3-trimethyl ammonium chloride modified chitosan (HTCC), followed by surface coating with HA-SH. The optimized NPHA-SH shows an average size of 100 nm with high encapsulation efficiency (91.1%) and loading capacity (38%). In vitro and ex vivo results confirm that NPHA-SH shows high mucus-penetration ability, improved intestinal retention and transepithelial transport property due to its thiolated surface and the ability of HA-SH coating to dissociate from the nanoparticle surface when across the mucosal layer. Oral administration of NPHA-SH to Type 1 diabetic rats yields high efficacy and an average relative bioavailability of 11.3%. These results demonstrate that the HA-SH coated core-shell nanoparticles are a promising oral delivery vehicle for protein therapeutics.

High-pure, single-phase, free of voids and high mass density AgGaS 2 polycrystalline was synthesized by a new method, i.e. two-temperature zone vapor-transporting together with the mechanical and melt temperature oscillation method (TVMMTOM), directly from high-purity (6 N) elements silver, gallium and sulfur with excess sulfur. The mechanism and advantages of the new method for synthesizing high-quality AgGaS 2 were discussed. It is found that the polycrystalline material synthesized by the new method is superior to that synthesized by the conventional method, what is more the new method can avoid the explosion of the synthetic quartz ampoule. Adopting the modified Bridgman method an integral and crack-free AgGaS 2 single crystal with diameter of 14 mm and length of 63 mm has been obtained. It was found that there was a (1 0 1) cleavage face and the four order X-ray spectrum of the {1 0 1} faces was observed. By the method of DSC analysis the melting and freezing points of the AgGaS 2 single crystal were about 995 and 955 °C. The transmission spectra of the AgGaS 2 sample of 10 × 8 × 2 mm 3 were obtained by means of UV and IR spectrophotometer. The limiting wavelength was 470 nm and the band gap was 2.64 eV. It can be found in the infrared spectrum that the infrared transmission was above 55% from 4000 to 800 cm −1 , and the infrared transmittance of the crystal is up to 63% at 10.6 μm, which is higher than that of the crystal grown using polycrystalline materials synthesized by the conventional method. The value of α in 10.6 μm was 0.267 cm −1 . Above mentioned results showed that the crystal was of good quality and TVMMTOM is preferable for synthesizing high-quality AgGaS 2 polycrystalline materials.

Good quality AgGa1−xInxSe2 (x=0.1–0.3) single crystals with 20 mm diameter and 60 mm length have been grown by an improved Bridgman method, i.e. descending ampoule with rotation and the real-time temperature compensation technique. The melt temperature oscillation method (MTOM) was used to synthesize high-purity single-phase AgGa1−xInxSe2 polycrystal that is free of voids. The crystallization process was carried out in the two-layer quartz ampoule with a seed pocket. The temperature gradient at the growth interface in the furnace was normally 20 °C cm−1 in the open bore, while it was 15 °C cm−1 with the ampoule in the furnace. The quality of the as-grown crystal was characterized by using X-ray diffraction, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), infrared (IR) spectrophotometer, etc. It was found that there is a {1 1 2} cleavage face in the as-grown crystal and the homogeneous growth steps on the {1 1 2} face were observed. The four-order diffraction peaks of the {1 0 1} faces were evident. The transmittance of the crystal sample of 2 mm thickness is up to 65% in the region of 700–6500 cm−1. The results demonstrated that the improved new growth method of AgGa1−xInxSe2 single crystals is promising and the quality of the grown crystals is good, and after annealing, the crystals can be used for IR nonlinear optical devices.

A good quality ZnGeP2 (ZGP) single crystal 15 mm in diameter and 40 mm in length was grown in a vertical three-zone tubular furnace by the modified Bridgman method, i.e. real-time temperature compensation technique (RTTCT) with descending ampoule. The starting material is high-pure and single-phase polycrystal of ZnGeP2 synthesized by the single-temperature zone and mechanical oscillation method (STZMOM). The as-grown single crystal was characterized by various methods, including X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive analyzer of X-ray (EDAX), and IR and UV spectrophotometers. It is found that there is a cleavage face of (1 1 2) and second-order XRD peaks of the {1 1 2} faces are observed, the IR transmittance of a sample of 2 mm thickness is above 55% in the range from 6000 to 800 cm−1, the absorption edge is near 612.5 nm and the band gap is about 2.02 eV. The absorption coefficient (α) is within 0.015–0.022 cm−1 at the spectral region 2–8 μm. The crystal has a stoichiometry ratio Zn:Ge:P=1:1.12:1.91 which is close to the ideal stoichiometry ratio of 1:1:2. All results demonstrate that the modified growth method is a new and promising method for the ZGP single crystal and the quality of as-grown crystal is good.

AgGaS2 has been studied using differential thermal analysis (DTA) technique. The melting point and solidification temperature of AgGaS2 were determined, indicating its large supercooling degree. A phase transformation point has been found. It was concluded by discussions with the DTA results and the phase diagram that the excess Ga2S3 came inevitably out of the AgGaS2 as precipitates of an intermediate phase (named Ag2Ga20S31). The results optimized the growth parameters and heat treatment procedures. Large, high optical quality AgGaS2 crystals have been obtained, and after heat treatment, it can be used for optical devices.

The effect of bromine methanol (BM) etching and NH 4 F/H 2 O 2 passivation on the Schottky barrier height between Au contact and semi-insulated (SI) p-Cd 1− x Zn x Te ( x ≈ 0.09–0.18) was studied through current–voltage ( I – V ) and capacitance–voltage ( C – V ) measurements. Near-infrared (NIR) spectroscopy technique was utilized to determine the Zn concentration . X-ray photoelectron spectroscopy (XPS) for surface composition analysis showed that BM etched sample surface left a Te 0 -rich layer, however, which was oxidized to TeO 2 and the surface [Te]/([Cd] + [Zn]) ratio restored near-stoichiometry after NH 4 F/H 2 O 2 passivation. According to I – V measurement, barrier height was 0.80 ± 0.02–0.85 ± 0.02 eV for Au/p-Cd 1− x Zn x Te with BM etching, however, it increased to 0.89 ± 0.02–0.93 ± 0.02 eV with NH 4 F/H 2 O 2 passivation. Correspondingly, it was about 1.34 ± 0.02–1.43 ± 0.02 eV and 1.41 ± 0.02–1.51 ± 0.02 eV by C – V method.

High-pure and single-phase AgGa1-xInxSe2 (x=0.2) polycrystalline was synthesized by the mechanical and temperature oscillation method. Adopting the modified Bridgman method an integral AgGa1-xInxSe2 single crystal with diameter of 14 mm and length of 35 mm has been obtained at the rate of 6 mm/day. It was found that there is a new cleavage face which was (101), and observed the four order X-ray spectrum of the {101} faces. By the method of DSC analysis the melting and freezing points of the AgGa1-xInxSe2 (x=0.2) single crystal were about 828°C and 790°C. The transmission spectra of the AgGa1-xInxSe2 (x=0.2) sample of 5×6×2 mm3 were obtained by means of UV and IR spectrophotometer. The limiting frequency was 774.316nm and the band gap was 1.6eV. It can be found in the infrared spectrum that the infrared transmission was above 60% from 4000cm-1 to 600cm-1. The value of α in 5.3µm and 10.6µm were 0.022cm-1 and 0.1cm-1 respectively. All results showed that the crystal was of good quality. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The phase equilibrium and the crystallization process of lead iodide (PbI 2 ) melt have been primarily investigated according to the lead–iodine phase diagram. It is found that the iodine evaporation and the segregated lead deposition are the two important factors that affect the PbI 2 crystal quality. The new method of Pulling U-type quartz growth ampoule has been made to impede the decomposition of PbI 2 and the vaporization and condensation of iodine. An orange and translucent PbI 2 single crystal of large size was obtained by the improved growth method, i.e. U-type ampoule pulling. Resistivity of the as-grown crystal is up to 4×10 11 Ω cm, and IR transmission is up to 45% in the region from 7800 to 450 cm −1 . Therefore, the improved growth method is a promising convenient new method for the growth of high quality PbI 2 crystals.

The impairment of intestinal motility and related infectious complications are the predominant clinical phenomenon in patients with severe acute pancreatitis (SAP). We aimed to investigate the effects of Da-Cheng-Qi decoction (DCQD) on the gastrointestinal injury in SAP patients and the potential mechanism involved in rats. DCQD was enema administered to 70 patients for 7 days in West China Hospital. Mortality and organ failure during admission were observed and blood samples for laboratory analysis were collected. We also experimentally examined plasma inflammatory cytokines in rat serum and carried the morphometric studies of the gut. Intestinal propulsion index and serum and tissue vasoactive intestinal peptide (VIP) were also detected. Though DCQD did not affect the overall incidence of organ failure, it shortened the average time of paralytic intestinal obstruction and decreased the morbidity of infectious complications in patients with SAP. Compared with untreated rats, the DCQD lowered the levels of proinflammatory cytokine and decreased the mean pathological intestinal lesion scores. The VIP level in intestinal tissue or serum in DCQD group was obviously lowered and intestinal propulsion index was significantly improved. In conclusion, DCQD has good effect on pancreatitis-associated intestinal dysmotility in patients and in rat models.

A crystal growth furnace with new structure was designed based on a conventional vertical resistance-wound tubular two-temperature-zone furnace in order to meet the requirements of growing high-quality AgGaS 2 single crystals. Large temperature gradients of 25–30 °C/cm at the growth interface and stable thermal profile were obtained. Integral and crack-free AgGaS 2 single crystals with fewer defects were grown successfully and reproducibly in the furnace mentioned above. A new cleavage face (1 0 1) was observed in the as-grown AgGaS 2 crystal. The crystal was characterized by using XRD and IR transmission microscopy. It is found that multiple diffraction peaks of the {1 0 1} faces are evident, and that IR transmittance is above 60%. The results show not only that the modified furnace is a new promising furnace for the growth of AgGaS 2 single crystals, but also that the quality of the grown crystal is good.