bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nickel Silicide Nanowire Arrays for Anti‐Reflective Electrodes in Photovoltaics
Authors: Dasgupta Neil P. , Xu Shicheng , Jung Hee Joon , Iancu Andrei , Fasching Rainer , Sinclair Robert , Prinz Fritz B. 
Published: May 2012

AbstractConductive nanowires (NWs) provide several advantages as a template and electrode material for solar cells due to their favorable light scattering properties. While the majority of NW solar cell architectures studied are based on semiconductor materials, metallic NWs could provide equivalent anti‐reflection properties, while acting as a low‐resistance back contact for charge transport, and facilitate light scattering in thin layers of semiconductors coated on the surface. However, fabrication of single‐crystalline highly anti‐reflective NWs on low‐cost, flexible substrates remains a challenge to drive down the cost of NW solar cells. In this study, metallic NixSi NW arrays are fabricated by a simple, bottom‐up, and low‐cost method based on the thermal decomposition of silane on the surface of flexible Ni foil substrates without the need for lithography, etching or catalysts. The optical properties of these NW arrays demonstrate broadband suppression of reflection to levels below 1% from 350 nm to 1100 nm, which is among the highest values reported for NWs. A simple route to control the diameter and density of the NWs is introduced based on variations in a carrier gas flow rate. A high‐resolution TEM, XRD and TEM‐EDS study of the NWs reveals that they are single crystalline, with the phase and composition varying between Ni2Si and NiSi. The nanowire resistivity is measured to be 10−4 Ω‐cm, suggesting their use as an efficient back electrode material for nanostructured solar cells with favorable light scattering properties.
Graphene Oxide Gel‐Derived, Free‐Standing, Hierarchically Porous Carbon for High‐Capacity and High‐Rate Rechargeable Li‐O2 Batteries
Authors: Wang Zhong‐Li , Xu Dan , Xu Ji‐Jing , Zhang Lei‐Lei , Zhang Xin‐Bo 
Published: May 2012

AbstractLithium‐oxygen (Li‐O2) batteries are one of the most promising candidates for high‐energy‐density storage systems. However, the low utilization of porous carbon and the inefficient transport of reactants in the cathode limit terribly the practical capacity and, in particular, the rate capability of state‐of‐the‐art Li‐O2 batteries. Here, free‐standing, hierarchically porous carbon (FHPC) derived from graphene oxide (GO) gel in nickel foam without any additional binder is synthesized by a facile and effective in situ sol‐gel method, wherein the GO not only acts as a special carbon source, but also provides the framework of a 3D gel; more importantly, the proper acidity via its intrinsic COOH groups guarantees the formation of the whole structure. Interestingly, when employed as a cathode for Li‐O2 batteries, the capacity reaches 11 060 mA h g−1 at a current density of 0.2 mA cm−2 (280 mA g−1); and, unexpectedly, a high capacity of 2020 mA h g−1 can be obtained even the current density increases ten times, up to 2 mA cm−2 (2.8 A g−1), which is the best rate performance for Li‐O2 batteries reported to date. This excellent performance is attributed to the synergistic effect of the loose packing of the carbon, the hierarchical porous structure, and the high electronic conductivity of the Ni foam.
Re‐ordering Chaotic Carbon: Origins and Application of Textured Carbon
Authors: Shakerzadeh M. , Loh G. C. , Xu N. , Chow W. L. , Tan C. W. , Lu C. , Yap R. C. C. , Tan D. , Tsang S. H. , Teo E. H. T. , Tay B. K. 
Published: May 2012

AbstractFormation of nanocrystals with preferred orientation within the amorphous carbon matrix has attracted lots of theoretical and experimental attentions recently. Interesting properties of this films, easy fabrication methods and practical problems associated with the growth of other carbon nanomaterials such as carbon nanotubes (CNTs) and graphene gives this new class of carbon nanostructure a potential to be considered as a replacement for some applications such as thermal management at nanoscale and interconnects. In this short review paper, the fabrication techniques and associated formation mechanisms of these nanostructured films have been discussed. Besides, electrical and thermal properties of these nanostructured films have been compared with CNTs and graphene.
The Current Move of Lithium Ion Batteries Towards the Next Phase
Authors: Kim Tae‐Hee , Park Jeong‐Seok , Chang Sung Kyun , Choi Seungdon , Ryu Ji Heon , Song Hyun‐Kon 
Published: May 2012

AbstractApplication targets of lithium ion batteries (LIBs) are moving from small‐sized mobile devices of information technology to large‐scale electric vehicles (xEVs) and energy storage systems (ESSs). Environmental issues and abruptly increasing power demands are pushing high performance energy storage devices or systems onto markets. LIBs are one of the most potential candidates as the energy storage devices mainly due to their high energy densities with fairly good rate capabilities and a fairly long cycle life. As battery systems become larger in terms of stored energy as well as physical size, the safety concerns should be more seriously cared. Each application target has its own specification so that electrode materials should be chosen to meet requirements of the corresponding application. This report diagnoses the current market trends of LIBs as a primary topic, followed by giving an overview of anode and cathode material candidates of LIBs for xEVs and ESSs based on their electrochemical properties.
A Highly Reversible Nano‐Si Anode Enabled by Mechanical Confinement in an Electrochemically Activated LixTi4Ni4Si7 Matrix
Authors: Son Seoung‐Bum , Kim Seul Cham , Kang Chan Soon , Yersak Thomas A. , Kim Yoon‐Chang , Lee Chun‐Gyoo , Moon Sung‐Hwan , Cho Jong Soo , Moon Jeong‐Tak , Oh Kyu Hwan , Lee Se‐Hee 
Published: May 2012

AbstractThis paper reports a Si‐Ti‐Ni ternary alloy developed for commercial application as an anode material for lithium ion batteries. Our alloy exhibits a stable capacity above 900 mAh g−1 after 50 cycles and a high coulombic efficiency of up to 99.7% during cycling. To enable a highly reversible nano‐Si anode, melt spinning is employed to embed nano‐Si particles in a Ti4Ni4Si7 matrix. The Ti4Ni4Si7 matrix fulfills two important purposes. First, it reduces the maximum stress evolved in the nano‐Si particles by applying a compressive stress to mechanically confine Si expansion during lithiation. And second, the Ti4Ni4Si7 matrix is a good mixed conductor that isolates nano‐Si from the liquid electrolyte, thus preventing parasitic reactions responsible for the formation of a solid electrolyte interphase. Given that a coulombic efficiency above 99.5% is rarely reported for Si based anode materials, this alloy's performance suggests a promising new approach to engineering Si anode materials.
Effect of partial delignification of kenaf bast fibers for radiation graft copolymerization
Authors: Mohamed Nor Hasimah , Tamada Masao , Ueki Yuji , Seko Noriaki 
Published: May 2012

AbstractMalaysian kenaf bast fiber was treated by acidic chlorite to be applied for a trunk polymer radiation‐induced graft copolymerization. The delignification conditions such as temperature, reaction time, and sodium chlorite (NaClO2) loading were optimized from the viewpoints of density, tensile strength, and reactivity of grafting. It was found that delignification condition at 80°C for 6 h with 0.5% NaClO2 gave 91% of lignin removal from the kenaf bast fibers. In this case, the density, fineness, and tensile strength of the kenaf fiber decreased about 46, 44, and 87%, respectively. Reactivity of grafting was evaluated using 4‐chloromethyl styrene to obtain widely available precursor materials. The partial delignified kenaf with residual lignin less than 2% resulted in degree of grafting of 134%, which is enough for precursor materials. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
SAXS study on deformation behavior of isotactic polypropylene under pressurized CO2
Authors: Osaka Noboru , Kono Fumiya , Saito Hiromu 
Published: May 2012

AbstractTensile‐deformation behavior and structure change of isotactic polypropylene (iPP) under pressurized CO2 were investigated by using in situ tensile‐deformation instruments and small‐angle X‐ray scattering (SAXS) measurements. Tensile strength including yield stress, plateau stress, and tensile modulus decreased with increase of CO2 pressure, suggesting that expansion of amorphous regions by absorbing CO2 allows crystalline lamellae to deform easily with less entanglement. Under CO2, the specimens became opaque beyond yield point and strong equatorial streaks appeared in two‐dimensional SAXS patterns. By using Ruland's streak method, they are attributed to formation of nanometer‐sized voids larger than the periodic distance of crystalline lamellae. An azimuthal profile of the lamellar peak was sharper under pressurized CO2 than that under ambient pressure. This meant that the easy rotation of the crystalline lamellae by CO2 results in the preferred orientation of the crystalline lamellae, which caused formation of the nanometer‐sized voids at the interspace in the polymer matrix between lamellar stacks. Owing to the formation of the nanometer‐sized voids, the elongation was enhanced in the second stage stretching of the stretched iPP at ambient pressure after depressurization. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
State diagram of phase transition temperatures and solvent‐induced recovery behavior of shape‐memory polymer
Authors: Lu Haibao 
Published: May 2012

AbstractIn this study we analyzed the phase and state transitions of shape‐memory polymers (SMPs)/solvent mixtures using the Flory–Huggins (FH) theory by extension of Vrentas and the Couchman–Karasz theory for glass transition, as well as Clausius–Clapeyron relation for melting transition. Using scaling relations of model parameters, we have obtained a theoretical prediction of state diagrams of the phase transition temperature and solvent‐induced recovery in SMPs. The inductive decrease in transition temperature is identified as the driving force for the solvent‐induced shape‐memory effect in SMPs Consequently, the thermodynamics of the polymer solution and the relaxation theory were employed to characterize the dependencies of shape recovery time on the FH parameter and the ratio of the molar volume of solute to solvent. With the estimated model parameters, we constructed the state diagram for SMP, which provides a powerful tool for design and analysis of phase transition temperatures and solvent‐induced recovery. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Synthesis and characterization of novel ultraviolet‐curing polyurethane acrylate/epoxy acrylate/SiO2 hybrid materials via sol–gel reaction
Authors: Yang Zehui , Ni Aiqing , Wang Jihui 
Published: May 2012

AbstractA series of ultraviolet‐curable hybrid materials was first synthesized here by sol–gel process based on tetraethoxysilane (TEOS) and polyurethane acrylate/epoxy acrylate resin. The functional groups in the hybrid materials were investigated by infrared spectroscopy (IR) analysis. The crystallinity of the hybrid materials and polymer resin was examined by X‐ray diffraction. Then, nearly uniform dispersion of SiO2 particles with the diameters ˜100 nm were revealed by field emission scanning electron micrographs. The surface morphology was scanned by atomic force microscope. And, thermal stability was measured by thermogravimetric analysis for hybrid materials produced from different mass ratio of TEOS to polymer. The results show that the hybrid material from the mass ratio of TEOS to polymer of 0.4 : 1 performed desirable optimal thermal stability and uniform microstructure which is suitable for optical fiber coating in high temperature application. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Pharmacokinetic profiling of efavirenz–emtricitabine–tenofovir fixed dose combination in pregnant and non‐pregnant rats
Authors: Nirogi Ramakrishna , Bhyrapuneni Gopinadh , Kandikere Vishwottam , Muddana Nageswararao , Saralaya Ramanatha , Komarneni Prashanth , Mudigonda Koteshwara , Mukkanti K. 
Published: May 2012

ABSTRACTDuring pregnancy, the disposition of various drugs is altered due to changes in physiological condition, maternal gastrointestinal absorption, gastric secretion and motility. A fixed dose combination of antiretrovirals is commonly prescribed for the treatment of HIV infection. There is a need to understand the pharmacokinetics and placental transfer of efavirenz–emtricitabine–tenofovir in fixed dose combination during pregnancy. The pharmacokinetics and placental transfer of efavirenz–emtricitabine–tenofovir fixed dose combination was evaluated in timed pregnant and non‐pregnant Sprague–Dawley rats at 30, 10, 15 mg/kg p.o., respectively. The plasma, placental tissue, amniotic fluid and fetal tissue concentrations were measured using high performance liquid chromatography combined with tandem mass spectrometric detector (LC‐MS/MS). To summarize, the pharmacokinetic profile of efavirenz remained similar in the pregnant and non‐pregnant rats. However, a considerable difference in the pharmacokinetics of emtricitabine and tenofovir was observed in pregnant and non‐pregnant rats. Efavirenz and emtricitabine showed appreciable placental, amniotic fluid and fetal exposure compared with tenofovir. The present study suggests that a profound impact on antiretroviral pharmacokinetics was observed during pregnancy and there is a need to monitor the exposure levels of each drug when administered as a fixed dose combination during pregnancy. Further studies to explore the pharmacokinetic parameters of fixed dose antiretrovirals during the preclinical stage in a timed‐pregnancy rat model are required. Such studies can help in the development of safe and effective medications with a reduced risk of perinatal transmission of HIV‐1 infection. Copyright © 2012 John Wiley & Sons, Ltd.
Interaction of cyproheptadine hydrochloride with human serum albumin using spectroscopy and molecular modeling methods
Authors: Jiang Hua , Chen Rongrong , Wang Hongcui , Pu Hanlin 
Published: May 2012

ABSTRACTThe interaction between cyproheptadine hydrochloride (CYP) and human serum albumin (HSA) was investigated by fluorescence spectroscopy, UV–vis absorption spectroscopy, Fourier transform infrared spectroscopy (FT‐IR) and molecular modeling at a physiological pH (7.40). Fluorescence of HSA was quenched remarkably by CYP and the quenching mechanism was considered as static quenching since it formed a complex. The association constants Ka and number of binding sites n were calculated at different temperatures. According to Förster's theory of non‐radiation energy transfer, the distance r between donor (human serum albumin) and acceptor (cyproheptadine hydrochloride) was obtained. The effect of common ions on the binding constant was also investigated. The effect of CYP on the conformation of HSA was analyzed using FT‐IR, synchronous fluorescence spectroscopy and 3D fluorescence spectra. The thermodynamic parameters ΔH and ΔS were calculated to be −14.37 kJ mol−1 and 38.03 J mol−1 K−1, respectively, which suggested that hydrophobic forces played a major role in stabilizing the HSA‐CYP complex. In addition, examination of molecular modeling indicated that CYP could bind to site I of HSA and that hydrophobic interaction was the major acting force, which was in agreement with binding mode studies. Copyright © 2012 John Wiley & Sons, Ltd.
Heavy Metal Contamination in Arable Soils and Vegetables around a Sulfuric Acid Factory, China
Authors: Liu Juan , Wang Jin , Qi Jianying , Li Xiangping , Chen Yongheng , Wang Chunlin , Wu Yingjuan 
Published: May 2012

AbstractThis study was designed to investigate heavy metal (Tl, Pb, Cu, Zn, and Ni) contamination levels of arable soils and vegetables grown in the vicinity of a sulfuric acid factory in the Western Guangdong Province, China. Health risks associated with these metals by consumption of vegetables were assessed based on the hazard quotient (HQ). The soils show a most significant contamination of Tl, followed by Pb, Cu, Zn, and Ni. The heavy metal contents (µg/g, dry weight basis) in the edible parts of vegetables range from 5.60 to 105 for Tl, below detection limit to 227 for Pb, 5.0–30.0 for Cu, 10.0–82.9 for Zn, and 0.50–26.0 for Ni, mostly exceeding the proposed maximum permissible level in Germany or China. For the studied vegetables, the subterranean part generally bears higher contents of Tl and Zn than the aerial part, while the former has lower contents of Cu and Ni than the latter. In addition, the results reveal that Tl is the major risk contributor for the local people since its HQ values are mostly much higher than 1.0. The potential health risk of Tl pollution in the food chain and the issue of food safety should be highly concerned and kept under continued surveillance and control.
Stability of P Saturated Water Treatment Residuals under Different Levels of Dissolved Oxygen
Authors: Wang Changhui , Fei Chengbo , Pei Yuansheng 
Published: May 2012

AbstractWater treatment residuals (WTRs) are effective phosphorus (P) immobilizers that have been used in constructed wetlands (CWs). In CWs, dissolved oxygen (DO) levels vary from location to location and fluctuate over time. Therefore, this work accessed the stability of P saturated ferric and alum water treatment residuals (FARs) under low (<1 mg/L), medium (2–4 mg/L), and high (5–8 mg/L) DO levels. In the experiments, which had a 40‐day duration, three stages of P release from the P saturated FARs were observed: an initial rapid P desorption stage, followed by a P re‐adsorption stage, and a P desorption balance stage. The strongest bonding between P and FARs occurred at the low DO level. A limited amount of Fe and Al was released from the P saturated FARs. Interestingly, the P in the FARs tended to transform from the Al bound P to the Fe bound P, and this transformation was stronger at lower DO levels. However, no more than 1.12% of the total P in the P saturated FARs was desorbed under any of these DO levels. Therefore, FARs can be considered as a safe P adsorption medium for CWs.
Removal of Selenium Species from Waters Using Various Surface‐Modified Natural Particles and Waste Materials
Authors: Yigit Nevzat O. , Tozum Seda 
Published: May 2012

AbstractWaste red mud and natural pumice/volcanic slag particles were surface modified and their selenium adsorption from waters was investigated. Acid activation/heat treatment of original red mud (ORM) particles significantly increased their micropore and external surface area and cumulative volume of pores. Iron oxide coating of pumice/slags and acid activation of ORM decreased their pHpzc values and increased surface acidity. Selenite/selenate adsorption on iron oxide surfaces and acid activated red mud (AARM) was very fast with approximately first‐order adsorption kinetics. Iron oxide coating of pumice/slag and acid activation of ORM particles significantly enhanced their selenite and selenate uptakes. Maximum Se adsorption capacities as high as 6.3 (mg Se/g adsorbent) were obtained by AARM. The extent of selenate uptakes by the surface modified particles was generally lower than those of selenite. Due to competition among Se species and other background water matrix for iron oxide adsorption sites, reduced selenite/selenate uptakes were found in natural water compared to single solute tests. Higher Se uptakes by iron oxide surfaces were found at pH 7.5 compared to pH 8.9, due to increased electrostatic repulsion among iron oxides and Se species at higher pH. The most effective adsorbents among the tested 17 different particles for Se uptake were AARM and iron oxide coated pumice. Se concentrations less than drinking water standards (5–10 µg/L) can be achieved by these particles. These low‐cost, natural, or recyclable waste particles appear to be promising adsorbents for Se removal after their surface modification.
Atomic Layer Deposition of Copper Oxide using Copper(II) Acetylacetonate and Ozone
Authors: Alnes Mari Endresen , Monakhov Edouard , Fjellvåg Helmer , Nilsen Ola 
Published: May 2012

AbstractWe report on the deposition of copper oxide by atomic layer deposition (ALD) using copper acetylacetonate (Cu(acac)2) and ozone (O3) as precursors. The aim is to deposit oxides of copper as possible candidates for materials in all‐oxide photovoltaics. The present study results in ALD‐type deposition of the tenorite phase of copper(II) oxide in a temperature window of 150 °C to ca. 230 °C, with a growth rate of ∼0.038 nm per cycle. The resulting ALD characteristics, with a relatively large ALD window in deposition temperature, should be well suited for combination with additional deposition processes for the formation of complex compounds. The film thickness is studied using X‐ray reflectivity (XRR), and phase is determined by X‐ray diffraction (XRD). Surface roughness is studied using atomic force microscopy (AFM), and X‐ray photoelectron spectroscopy (XPS) is used to investigate the chemical state of the deposited films.
A pair of transmembrane receptors essential for the retention and pigmentation of hair
Authors: Han Rong , Beppu Hideyuki , Lee Yun‐Kyoung , Georgopoulos Katia , Larue Lionel , Li En , Weiner Lorin , Brissette Janice L. 
Published: May 2012

AbstractHair follicles are simple, accessible models for many developmental processes. Here, using mutant mice, we show that Bmpr2, a known receptor for bone morphogenetic proteins (Bmps), and Acvr2a, a known receptor for Bmps and activins, are individually redundant but together essential for multiple follicular traits. When Bmpr2/Acvr2a function is reduced in cutaneous epithelium, hair follicles undergo rapid cycles of hair generation and loss. Alopecia results from a failure to terminate hair development properly, as hair clubs never form, and follicular retraction is slowed. Hair regeneration is rapid due to premature activation of new hair‐production programs. Hair shafts differentiate aberrantly due to impaired arrest of medullary‐cell proliferation. When Bmpr2/Acvr2a function is reduced in melanocytes, gray hair develops, as melanosomes differentiate but fail to grow, resulting in organelle miniaturization. We conclude that Bmpr2 and Acvr2a normally play cell‐type‐specific, necessary roles in organelle biogenesis and the shutdown of developmental programs and cell division. genesis 1–18, 2012. © 2012 Wiley Periodicals, Inc.
A conditional allele of Rspo3 reveals redundant function of R‐spondins during mouse limb development
Authors: Neufeld Stanley , Rosin Jessica M. , Ambasta Anshula , Hui Kristen , Shaneman Venessa , Crowder Ray , Vickerman Lori , Cobb John 
Published: May 2012

AbstractSummary: R‐spondins are secreted ligands that bind cell surface receptors and activate Wnt/β‐catenin signaling. Human mutations and gene inactivation studies in mice have revealed a role for these four proteins (RSPO1‐4) in diverse developmental processes ranging from sex determination to limb development. Among the genes coding for R‐spondins, only inactivation of Rspo3 shows early embryonic lethality (E10.5 in mice). Therefore, a conditional allele of this gene is necessary to understand the function of R‐spondins throughout murine development. To address this need, we have produced an allele in which loxP sites flank exons 2–4 of Rspo3, allowing tissue‐specific deletion of these exons in the presence of Cre recombinase. We used these mice to investigate the role of Rspo3 during limb development and found that limbs ultimately developed normally in the absence of Rspo3 function. However, severe hindlimb truncations resulted when Rspo3 and Rspo2 mutations were combined, demonstrating redundant function of these genes. genesis 50:741–749, 2012. © 2012 Wiley Periodicals, Inc.