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In this work, the ferroelectric characteristic of a 5 nm Hf0.5Zr0.5O2 (HZO) metal-ferroelectric-insulator-semiconductor (MFIS) device is enhanced through strained complementary metal oxide semiconductor (CMOS)-compatible TiN electrode engineering. Strained TiN top-layer electrodes with different nitrogen (N) concentrations are deposited by adjusting the sputtering process conditions. The TiN electrode with 18% N exhibits a compressive characteristic, which induces tensile stress in a 5 nm HZO film. A device with 18% N in TiN shows a higher remanent polarization (2Pr) and larger capacitance value than the compared sample, indicating that the strained TiN is promising for enhancing the ferroelectricity of sub-5 nm HZO devices.

A method for fabricating high-efficiency Cu2ZnSn(S,Se)4 (CZTSSe) solar cells is presented, and it is based on a non-explosive, low-cost, and simple solution process followed by a two-step heat treatment. 2-Methoxyethanol was used as a solvent, and Cu, Zn, Sn, chloride salts, and thiourea were used as solutes. A CZTSSe absorber was prepared by sulfurising and then selenising an as-coated Cu2ZnSnS4 (CZTS) film. Sulfurisation in a sulfur vapour filled furnace for a long time (2 h) enhanced the crystallisation of the as-coated CZTS film and improved the stability of the CZTS precursor, and selenisation promoted further grain growth to yield a void-free CZTSSe film. Segregation of Cu and S at the grain boundaries, the absence of a fine-grain bottom layer, and the large grain size of the CZTSSe absorber were the main factors that enhanced the grain-to-grain transport of carriers and consequently the short-circuit current ( Jsc) and efficiency. The efficiency of the CZTS solar cell was 5.0%, which increased to 10.1% after selenisation. For the 10.1% CZTSSe solar cell, the external quantum efficiency was approximately 80%, the open-circuit voltage was 450 mV, the short-circuit current was 36.5 mA/cm2, and the fill factor was 61.9%. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Non-vacuum processing combining with roll-to-roll manufacturing technology is available to fabricate large-area and low-cost flexible thin film solar cell. In this work, Cu(In, Ga)Se2 (CIGS) solar cells were fabricated on flexible stainless steel substrates with the CIGS absorber layer prepared using ink-printing technique and selenization process. A Cr diffusion barrier layer was sputtered onto the substrate before the deposition of Mo back contact to prevent the diffusion of detrimental elements like Fe from the substrate. The Cd-free buffer layer of In2S3, instead of the traditional CdS, was deposited on the surface of CIGS absorber layer for non-toxic and environmentally friendly consideration. The CIGS absorber layer exhibits a bilayer structure with the upper layer with large CuInSe2 grains and the bottom layer with small Cu(In, Ga)Se2 grains. The best performance of flexible CIGS solar cell achieves to an efficiency of 11.1%, a Voc of 0.45V, a Jsc of 37.7mA/cm2 and a fill factor of 0.66 with an active area of 0.14cm2. [Copyright &y& Elsevier]

Non-crystalline Cu2ZnSnS4(CZTS) nano-particles were fabricated by hydrothermal method. CZTS nano-particles that have different Cu/(Zn+Sn) ratio (0.77, 0.89, 1.02) were separately prepared. The morphology, composition and crystal structure of the as-prepared nano-particles and the vulcanized films were investigated by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffractometry, and Raman spectroscopy. When the temperature and time of vulcanization exceeded 400°C and 60min, respectively, the Cu-rich phase (Cu3SnS4) emerged. Sn lost during vulcanization. CZTS sample with 0.77 Cu content (Cu/(Zn+Sn) =0.77) showed pure kesterite CZTS without secondary phases when they were vulcanized at 400°C for 60min. [ABSTRACT FROM AUTHOR]

We report electrochemical measurements using in situ Raman spectroscopy at graphene/D 2 O interfaces under extremely low applied potentials. Here, the hydrophobic and catalytically inert nature of graphene and the insulating nature of the deionized (DI) water enables potentials as low as V applied = -7 V vs Ag/AgCl to be applied without exceeding 200 μA/cm 2 of current density. At higher currents, bubble formation (i.e., hydrogen evolution reaction) prohibits reliable spectra from being obtained from the electrode surface. Using CaF 2 as the supporting substrate enables significantly lower reducing potentials to be reached compared to glass substrates, likely due to trapped charge and impurities in the glass substrate. G band Raman spectra taken under various applied electrochemical potentials exhibit a linear relationship between the G band shift (Δω G ) and the applied potential, with blueshifts as high as Δω G = 18 cm -1 . These large Raman shifts indicate a large change in the Fermi level of Δ E F = -0.43 eV for graphene electrodes in contact with water, favoring reduction half-reactions. Based on the solution resistance measurement, there is a V IR = 3.1 V voltage drop across the solution for D 2 O (when the applied potential was V applied = -7 V vs Ag/AgCl) and the effective reducing potential on the working electrode is V effective = -3.9 V vs Ag/AgCl. We have also tested these graphene electrodes in ionic liquids [DEME][TFSI], which are limited to applied potentials above V applied = -2.7 V vs Ag/AgCl and a corresponding shift in the Fermi level Δ E F = -0.32 eV, indicating that pure water can provide a more robust electrolyte for reaching low reducing potentials than ionic liquids.

We report spectroscopic measurements of the local pH and p K a at an electrode/electrolyte interface using surface enhanced Raman scattering (SERS) spectroscopy of 4-mercaptobenzoic acid (4-MBA). In acidic and basic solutions, the protonated and deprotonated carboxyl functional groups at the electrode surface exist in the solution as -COOH and -COO - , which have different Raman active vibrational features at around 1697 and 1414 cm -1 , respectively. In pH neutral water, as the applied electrochemical potential is varied from negative to positive, the acidic form of the 4-MBA ( i.e. , -COOH) decreases in Raman intensity and the basic form ( i.e. , -COO - ) increases in Raman intensity. The change in local ion concentration is due to the application of electrochemical potentials and the accumulation of ions near the electrode surface. Under various applied potentials, the ratio of 1697 and 1587 cm -1 (pH-independent) peak areas spans the range between 0.7 and 0, and the ratio of the 1414 and 1587 cm -1 peak areas ranges from 0 to 0.3. By fitting these data to a normalized sigmoid function, we obtain the percentage of surface protonation/deprotonation, which can be related to the p K a and pH of the system. Thus, we can measure the local p K a at the electrode surface using the surface enhanced Raman signal of the 4-MBA.

By combining the composting process with soil culture experiment, we conducted an experiment with four treatments, including conventional chemical fertilizer (CK), chemical fertilizer + compost maturity reaching 50% germination index (GI, the same below) organic fertilizer (CO1), chemical fertilizer + compost maturity reaching 80% GI organic fertilizer (CO2), chemical fertilizer + compost maturity reaching 100% GI organic ferti-lizer (CO3). We measured soil microbial biomass nitrogen (MBN), mineral nitrogen (NH 4 + -N, NO 3 - -N), net nitrification rate, microbial biomass carbon (MBC), dissolved organic carbon (DOC), soil urease and soil protease, aiming to reveal the regulatory effect of soil MBN on mineral nitrogen. The results showed that organic fertilizer application significantly increased MBN and NH 4 + -N concentrations by 50.1%-62.4% and 109.9%-147.1%, reduced NO 3 - -N concentration and net nitrification rate by 23.3%-46.8%, and 26.2%-51.5%, and enhanced MBC, DOC, urease and protease activities by 33.8%-69.6%, 7.4%-20.8%, 11.2%-69.0% and 9.4%-25.1%, respectively. The change ranges of CO2 and CO3 were significantly higher than CO1. Redundancy analysis (RDA) and structural equation model (SEM) results showed that the application of organic fertilizer with higher degree of maturity (GI≥80%) positively regulated soil MBC, MBN, NH 4 + -N, and the activities of urease and protease, but had a negative effect on soil net nitrification rate. The combined application of chemical fertilizers and high decomposed organic fertilizers could significantly increase soil MBN and NH 4 + -N contents, as well as soil urease and protease activities, but reduce soil net nitrification rate. To efficiently utilize organic solid wastes, it is recommended to use chemical fertilizer in combination of organic fertilizers with 80% decomposing degree in practical production to reduce the cost in both economy and time.

We examined the correlation between changes of root morphology and endogenous hormones in intercropping systems of wheat and faba bean under different phosphorus levels by hydroponics. Compared with monocropping wheat (MW), the intercropping of wheat and faba bean (W∥F) significantly increased root length of wheat, reduced root average diameter of wheat, and increased root surface area under the condition of 1/2P (low P) level. At the conventional phosphorus level, intercropping significantly reduced root average diameter of wheat, and increased root length and root surface area. Compared with monocropping faba bean (MF), W∥F significantly promoted the growth of faba bean root and increased root surface area of faba bean. At the level of 1/2P, intercropping significantly increased the content of auxin (IAA), abscisic acid (ABA), sali-cylic acid (SA) and jasmonic acid (JA). At the conventional phosphorus level, intercropping could significantly increase the content of IAA, ABA and JA in wheat root, while no significant difference in the SA content of wheat root between monocropping and intercropping wheat was found. Intercropping could increase the content of ABA and SA in faba bean roots, but did not affect IAA and JA contents of faba bean roots. There was no significant correlation between the contents of endogenous hormones (IAA, ABA, SA and JA) and root morphology (root length, root average diameter and root surface area) of wheat and faba bean roots in wheat or faba bean monocropping system. In wheat and faba bean intercropping system, there was a positive correlation between IAA contents of wheat and faba bean and their root length and root surface area. W∥F enhanced IAA of wheat and faba bean root, which was an important factor driving the change of root morphology in the intercropping system of wheat and faba bean.

Objective: To explore the feasibility of inducing the differentiation of human adipose tissue-derived stem cells (ADSCs) into Leydig cells in vitro., Methods: We isolated ADSCs by digestion with Collagenase I from the subcutaneous adipose tissue, cultured them in the DMEM/F12 medium with 10% fetal bovine serum, and detected the expression of vimentin by immunohistochemistry. We exposed the ADSCs to different concentrations of human chorionic gonadotropin (HCG) for different times, determined the expression of StAR mRNA by real-time PCR, and measured the HCG-induced proliferation of ADSCs by MTT. After a week of induction by HCG and DMSO, we conducted 3beta-HSD immunohistochemistry, and detected the testosterone level in the supernatant and lysis of the cells by radioimmunoassay., Results: The ADSCs grew well with a positive expression of vimentin. The expression of the StAR gene was positively correlated with the increased concentration of HCG, reaching the peak at HCG 10 U/ml in 1 week culture. The proliferation of ADSCs was significantly increased by HCG induction. A positive expression of 3beta-HSD was observed after 1 week induction with HCG 10 U/ml and DMSO 3.2 x 10(-6)mol/L., Conclusion: HCG enhances the expression of the StAR gene and the proliferation of ADSCs. Induced by HCG 10 U/ml and DMSO 3.2 x 10(-6) mol/L, ADSCs tend to differentiate into Leydig cells.

Objective: To observe the influence of the organophosphate insecticide dichlorvos on the apoptosis of Leydig cells in the male offspring of the SD rats exposed to dichlorvos, and to investigate the role of the changes of Leydig cells in genitourinary malformation., Methods: Twenty-one pregnant SD rats were divided into a corn oil control group and 6 dichlorvos groups, the former given by gavage 1.0 ml corn oil daily, and the latter dichlorvos at the dose of 1, 4, 8, 16, 20 and 24 mg/kg daily from the 12th to 17th day of conception. After birth, 5 male neonates were randomly selected from each of the control and dichlorvos groups, and their testes were harvested to be analyzed by HE staining, immunohistochemistry with anti-caspase-3 antibodies and DAPI fluorescent staining. At 90 days after birth, another 5 of the male offspring were taken from each group and their testes were collected for the same analyses., Results: Statistically significant differences were found in the number of both the caspase-3 positive and DAPI labeled Leydig cells in the testes of the rat offspring between the corn oil and the 4, 8, 16, 20 and 24 mg/kg dichlorvos groups (P < 0.05), but not between the control and the 1 mg/kg dichlorvos groups (P > 0.05). The apoptosis of Leydig cells was increased in the male offspring of the dichlorvos-exposed SD rats in a dose-dependent manner., Conclusion: Exposure of pregnant rats to dichlorvos can increase the apoptosis of Leydig cells in the male offspring, which, in turn, may reduce the number of Leydig cells, interfere with the testis function during the embryonic period, and damage the development of the genitourinary system.

Objective: To observe the changes of peristalsis of small intestine in guinea pigs after administration of traditional Chinese medicines activating blood to resolve stasis (Compound Danshen Decoction, CDSD) or/and medicines dredging intestines (Dachengqi Decoction, DCQD), and to explore the synergetic or intensive effect of CDSD on DCQD., Methods: By means of BL-420 Biological Experimental System, peristalsis of small intestine was recorded and analyzed following administration of DCQD, CDSD or Huoxue Chengqi Decoction (HXCQD, compound of CDSD and DCQD) respectively in different experimental periods., Results: The amplitude and frequency of intestinal peristaltic wave obviously increased following administration of the three decoctions, but HXCQD appeared to be most dominantly., Conclusion: The effect of DCQD can be further enhanced by combining use of CDSD, suggesting that the traditional Chinese medicines activating blood to resolve stasis have an intensive effect on medicines dredging intestines.