bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthetic Developments of Nontoxic Quantum Dots
Authors: Das Adita , Snee Preston T. 
Published: November 2015

AbstractSemiconductor nanocrystals, or quantum dots (QDs), are candidates for biological sensing, photovoltaics, and catalysis due to their unique photophysical properties. The most studied QDs are composed of heavy metals like cadmium and lead. However, this engenders concerns over heavy metal toxicity. To address this issue, numerous studies have explored the development of nontoxic (or more accurately less toxic) quantum dots. In this Review, we select three major classes of nontoxic quantum dots composed of carbon, silicon and Group I–III–VI elements and discuss the myriad of synthetic strategies and surface modification methods to synthesize quantum dots composed of these material systems.
Effect of Molecular Coupling on Ultrafast Electron‐Transfer and Charge‐Recombination Dynamics in a Wide‐Gap ZnS Nanoaggregate Sensitized by Triphenyl Methane Dyes
Authors: Debnath Tushar , Maity Partha , Dana Jayanta , Ghosh Hirendra N. 
Published: November 2015

AbstractWide‐band‐gap ZnS nanocrystals (NCs) were synthesized, and after sensitizing the NCs with series of triphenyl methane (TPM) dyes, ultrafast charge‐transfer dynamics was demonstrated. HRTEM images of ZnS NCs show the formation of aggregate crystals with a flower‐like structure. Exciton absorption and lumimescence, due to quantum confinement of the ZnS NCs, appear at approximately 310 and 340 nm, respectively. Interestingly, all the TPM dyes (pyrogallol red, bromopyrogallol red, and aurin tricarboxylic acid) form charge‐transfer complexes with the ZnS NCs, with the appearance of a red‐shifted band. Electron injection from the photoexcited TPM dyes into the conduction band of the ZnS NCs is shown to be a thermodynamically viable process, as confirmed by steady‐state and time‐resolved emission studies. To unravel charge‐transfer (both electron injection and charge recombination) dynamics and the effect of molecular coupling, femtosecond transient absorption studies were carried out in TPM‐sensitized ZnS NCs. The electron‐injection dynamics is pulse‐width‐limited in all the ZnS/TPM dye systems, however, the back electron transfer differs, depending on the molecular coupling of the sensitizers (TPM dyes). The detailed mechanisms for the above‐mentioned processes are discussed.
Cu‐Based Nanocomposites as Multifunctional Catalysts
Authors: Kumar Bharat , Rao Gyandshwar Kumar , Saha Soumen , Ganguli Ashok K. 
Published: November 2015

AbstractHerein, we report the synthesis of Cu/Cu2O nanocomposites by a one‐step hydrothermal process at 180 °C, for which the resulting morphology is dependent on the hydrothermal reaction time (24, 72, and 120 h). With a longer reaction time of 120 h, a rod‐shape morphology is obtained, whereas at 72 and 24 h assemblies of nanoparticles are obtained. The rod‐shaped (120 h) particles of the Cu/Cu2O nanocomposites show a much higher efficiency (6.3 times) than the agglomerates and 2.5 times more than the assemblies of nanoparticles for the hydrogen‐evolution reaction. During the oxygen‐evolution reaction, the nanorods produce a current that is 5.2 and 3.7 times higher than that produced by the agglomerated and assembled nanoparticles, respectively. The electrocatalysts are shown to be highly stable for over 50 cycles. As catalysts for organic synthesis, a 100 % yield is achieved in the Sonogashira cross‐coupling reaction with the nanorods, which is higher than with the other nanocomposite particles. This result demonstrates the significant enhancement of yield obtained with the nanorods for cross‐coupling reactions.
Scalable Preparation of Ternary Hierarchical Silicon Oxide–Nickel–Graphite Composites for Lithium‐Ion Batteries
Authors: Wang Jing , Bao Wurigumula , Ma Lu , Tan Guoqiang , Su Yuefeng , Chen Shi , Wu Feng , Lu Jun , Amine Khalil 
Published: November 2015

AbstractSilicon monoxide is a promising anode candidate because of its high theoretical capacity and good cycle performance. To solve the problems associated with this material, including large volume changes during charge‐discharge processes, we report a ternary hierarchical silicon oxide–nickel–graphite composite prepared by a facile two‐step ball‐milling method. The composite consists of nano‐Si dispersed silicon oxides embedded in nano‐Ni/graphite matrices (Si@SiOx/Ni/graphite). In the composite, crystalline nano‐Si particles are generated by the mechanochemical reduction of SiO by ball milling with Ni. These nano‐Si dispersed oxides have abundant electrochemical activity and can provide high Li‐ion storage capacity. Furthermore, the milled nano‐Ni/graphite matrices stick well to active materials and interconnect to form a crosslinked framework, which functions as an electrical highway and a mechanical backbone so that all silicon oxide particles become electrochemically active. Owing to these advanced structural and electrochemical characteristics, the composite enhances the utilization efficiency of SiO, accommodates its large volume expansion upon cycling, and has good ionic and electronic conductivity. The composite electrodes thus exhibit substantial improvements in electrochemical performance. This ternary hierarchical Si@SiOx/Ni/graphite composite is a promising candidate anode material for high‐energy lithium‐ion batteries. Additionally, the mechanochemical ball‐milling method is low cost and easy to reproduce, indicating potential for the commercial production of the composite materials.
Catalytic Upgrading of 5‐Hydroxymethylfurfural to Drop‐in Biofuels by Solid Base and Bifunctional Metal–Acid Catalysts
Authors: Bohre Ashish , Saha Basudeb , Abu‐Omar Mahdi M. 
Published: November 2015

AbstractDesign and synthesis of effective heterogeneous catalysts for the conversion of biomass intermediates into long chain hydrocarbon precursors and their subsequent deoxygenation to hydrocarbons is a viable strategy for upgrading lignocellulose into distillate range drop‐in biofuels. Herein, we report a two‐step process for upgrading 5‐hydroxymethylfurfural (HMF) to C9 and C11 fuels with high yield and selectivity. The first step involves aldol condensation of HMF and acetone with a water tolerant solid base catalyst, zirconium carbonate (Zr(CO3)x), which gave 92 % C9–aldol product with high selectivity at nearly 100 % HMF conversion. The as‐synthesised Zr(CO3)x was analysed by several analytical methods for elucidating its structural properties. Recyclability studies of Zr(CO3)x revealed a negligible loss of its activity after five consecutive cycles over 120 h of operation. Isolated aldol product from the first step was hydrodeoxygenated with a bifunctional Pd/Zeolite‐β catalyst in ethanol, which showed quantitative conversion of the aldol product to n‐nonane and 1‐ethoxynonane with 40 and 56 % selectivity, respectively. 1‐Ethoxynonane, a low oxygenate diesel range fuel, which we report for the first time in this paper, is believed to form through etherification of the hydroxymethyl group of the aldol product with ethanol followed by opening of the furan ring and hydrodeoxygenation of the ether intermediate.
High‐performance Polymer Membranes with Multi‐functional Amphiphilic Micelles for CO2 Capture
Authors: Kim Sang Jin , Jeon Harim , Kim Dong Jun , Kim Jong Hak 
Published: November 2015

AbstractInvited for this month′s cover is the group of Jong Hak Kim at Yonsei University in South Korea. The image shows how CO2 selectively permeates through the polymer membrane containing multi‐functional amphiphilic poly(dimethylsiloxane)‐g‐poly(oxyethylene methacrylate) (PDMS‐g‐POEM) comb copolymer micelles. The microphase‐separated structure consists of PDMS cores and CO2‐philic POEM corona. The Full Paper itself is available at 10.1002/cssc.201501063.
Towards Cardiolite‐Inspired Carbon Monoxide Releasing Molecules – Reactivity of d4, d5 Rhenium and d6 Manganese Carb­onyl Complexes with Isocyanide Ligands
Authors: Kottelat Emmanuel , Chabert Valentin , Crochet Aurélien , Fromm Katharina M. , Zobi Fabio 
Published: November 2015

AbstractCarbon monoxide releasing molecules (CORMs) are investigated widely in synthetic and medicinal chemistry owing to the potential therapeutic applications of the CO gas. Organometallic carbonyl complexes are best suited to play the role of CO carriers as they allow the exogenous release of CO under controlled conditions, and the toxicity of the gas can be overcome. With the long‐term goal of developing CORMs with similar properties to those of the sesta‐methoxyisobutylisonitrile (sesta‐mibi) 99mTc complex (Cardiolite), we have studied the reactivity of isocyanide ligands towards 16‐ and 17‐electron cis‐[Re(CO)2Br4]–/2– species and the [Mn(CO)5Br] complex. Six different isocyanide ancillary ligands (CNR), including mibi, were selected for this study. Their reactions with cis‐dicarbonyl ReIII and ReII complexes were accompanied by two‐ and one‐electron reduction of the metal center and resulted in the formation of stable cis‐mer‐[Re(CO)2(CNR)3Br] species, whereas the same reactions with [Mn(CO)5Br] gave fac‐[Mn(CO)3(CNR)2Br] compounds. All of the complexes were fully characterized, and single‐crystal X‐ray diffraction structure determinations were performed for selected species. In addition, unique monocarbonyl complexes were obtained from the reactions of cis‐[Re(CO)2Br4]– (1) with tert‐butyl isocyanide and cis‐[Re(CO)2Br4]2– (2) with mibi. The species, a heptacoordinate ReIII and a hexacoordinate ReII complex, respectively, were also characterized structurally. The CO‐releasing profiles, the cytotoxic effects against 3T3 fibroblast cells, and the antibacterial properties of the compounds were also investigated.
Synthesis and Photoluminescence Properties of CuI Complexes with Chelating Phosphinito Phosphinine Ligands
Authors: Chen Xiaodan , Li Zhongshu , Yanan Fan , Grützmacher Hansjörg 
Published: November 2015

AbstractThe reaction between the sodium salt of 2‐oxyphosphinine and diphenylchlorophosphine leads to 2‐diphenylphosphinite phosphinine as a new chelating ligand. Copper(I) complexes are easily and quantitatively obtained when this compound is reacted with CuIX (X = Cl, Br, I). The optical properties of these complexes were investigated; all of them show phosphorescence in the solid state at room temperature and emit orange‐red light in the range 658 to 702 nm with average lifetimes from 19.98 to 25.01 μs. The emission wavelength is tuned by the nature of the halide ligand: Cl–, which leads to a larger ligand‐field splitting, gives the longest emission wavelength, whereas I–, which generates a smaller ligand‐field splitting, leads to the shortest emission wavelength.
Synthesis, Structures and Properties of Half‐Sandwich Nickel(II) Complexes with Backbone‐Modified NHC Ligands
Authors: Banach Łukasz , Guńka Piotr A. , Górska Dominika , Podlewska Maja , Zachara Janusz , Buchowicz Włodzimierz 
Published: November 2015

AbstractA series of seven nickel complexes [Ni(η5‐C5H5)(X)(NHC)] (X = Cl or Br; NHC = N‐heterocyclic carbene) containing backbone‐modified NHC ligands was prepared by treatment of nickelocene with the corresponding NHC·HX salts or, in the case of complex 1h [Ni(η5‐C5H5)(Cl)(IMesO)] (IMesO = 4‐oxo‐1,3‐bis(2,4,6‐trimethylphenyl)imidazolin‐2‐ylidene), by deprotection of the corresponding NHC ligand in complex 1g [Ni(η5‐C5H5)(Cl)(IMesOPiv)] [IMesOPiv = 4‐(pivaloyloxy)‐1,3‐bis(2,4,6‐trimethylphenyl)imidazol‐2‐ylidene]. Single‐crystal X‐ray structures were determined for complexes 1d [Ni(η5‐C5H5)(Cl)(Bn2‐bimy)] (Bn2‐bimy = 1,3‐dibenzylbenzimidazolin‐2‐ylidene), 1g and 1h. The coordination spheres around the nickel atoms resemble those of d8 NiL4 square‐planar complexes, with Ni–C(Cp) bond length differentiation and C–C bond alternation in Cp ligands being taken into account. Desymmetrization of the five‐membered heterocyclic ring and a tautomeric equilibrium were observed for complex 1h. All new complexes are efficient precatalysts in three C–C bond‐forming reactions (polymerization of styrene, polymerization of methyl methacrylate, Suzuki–Miyaura cross‐coupling).
Diastereoselective Synthesis of the A‐B‐C Tricyclic Ring Structure of Stemocurtisine
Authors: Dau Xuan Duc , Willis Anthony C. , Pyne Stephen G. 
Published: November 2015

AbstractThe diastereoselective synthesis of the A‐B‐C tricyclic ring structure of the Stemona alkaloid stemocurtisine is described. This tricyclic precursor to the natural product was obtained in 19 steps from a known vinyl iodide. Attempts to prepare the C‐3a–C‐11 ether moiety of this alkaloid through a photochemically induced oxidative cyclization method were unsuccessful because of the cleavage of the A‐ring.
Recent Advances in First‐Row‐Transition‐Metal‐Catalyzed Dehydrogenative Cou­pling of C(sp3)–H Bonds
Authors: Miao Jinmin , Ge Haibo 
Published: November 2015

AbstractTransition‐metal‐catalyzed cross dehydrogenative coupling is a highly efficient tool for functionalization of C(sp3)–H bonds. In particular, the inexpensive first‐row transition metals have been demonstrated as effective catalysts in this process. This microreview summarizes recent progress in two classes of first‐row‐transition‐metal‐catalyzed dehydrogenative reactions: intramolecular cyclization for C–C bond formation, and directed site‐selective C–H functionalization. These transformations provide concise and practical approaches for preparation of various organic compounds, but so far they are underdeveloped.
Feed‐Splitting as Energy‐Saving Technique in the Heterogeneous Distillation of Ethanol–Water Azeotropes
Authors: Tavan Yadollah , Shahhosseini Shahrokh 
Published: November 2015

AbstractThe separation of azeotropic mixtures is one of the most energy‐intensive separations in petrochemical processes. In this study the effect of feed‐splitting on one arrangement with heat integration is investigated in order to reduce the energy demand of the heterogeneous azeotropic distillation of ethanol–water process, using Hysys process simulation software and relevant optimization analysis. The total energy demands of the new and conventional processes are compared, revealing that a 27.5 % reduction in energy is possible for the intensified process.
Lead exposure reduces carotenoid-based coloration and constitutive immunity in wild mallards
Authors: Vallverdú-Coll Núria , Mougeot François , Ortiz-Santaliestra Manuel E. , Rodriguez-Estival Jaime , López-Antia Ana , Mateo Rafael 
Published: November 2015

Abstract

The ingestion of spent lead (Pb) from ammunition is a known cause of mortality in waterfowl, but little is known about sublethal effects produced by Pb poisoning on birds, especially in wild populations. The authors studied potential sublethal effects associated with Pb exposure in mallards (Anas platyrhynchos) from the Ebro delta (northeastern Spain) after a ban on Pb ammunition. They analyzed the relationships between blood Pb levels and oxidative stress, immune response, and carotenoid-based coloration, which are known to be influenced by oxidative stress. Levels of Pb were reduced by half from 6 yr to 9 yr after the ban. Lipid peroxidation was positively related to Pb levels in females. The δ-aminolevulinic acid dehydratase activity was suppressed by Pb exposure and negatively associated with the activity of antioxidant enzymes. Carotenoid levels were positively associated with blood Pb concentration in both sexes, and males with higher Pb levels presented a less intense coloration in legs and beak. Levels of Pb were positively related to hemolytic activity of circulating immune system components and negatively related to lysozyme levels. In summary, Pb exposure was associated in a gender-specific way with increased oxidative stress, consequences on color expression, and impaired constitutive immunity. In females, antioxidants seemed to be allocated mostly in reproduction rather than in self-maintenance, whereas males seemed to better maintain oxidative balance to the detriment of coloration. Environ Toxicol Chem 2016;35:1516–1525. © 2015 SETAC
A low‐complexity turbo MUD for MU–MIMO SC‐FDMA systems
Authors: Chang Yu‐Kuan , Ueng Fang‐Biau , Yang Ying‐Mu 
Published: November 2015

AbstractIn order to provide high‐quality services, current communication systems require high data‐transmission rate and good error performance. Single carrier‐frequency division multiple access (SC‐FDMA) has been adopted as the uplink transmission standard in fourth generation cellular network to enable the power efficiency transmission in mobile station. Multi‐user multiple‐input multiple‐output (MU–MIMO) technologies are adopted in many standards to enhance the data rate and the link robustness. By combining MU–MIMO techniques with the SC‐FDMA modulation scheme, MU–MIMO SC‐FDMA systems can achieve high data rates over broadband wireless channels. For MU–MIMO SC‐FDMA systems, possible detection techniques include zero‐forcing detection, minimum mean squared error detection and maximum likelihood detection (MLD). Among these schemes, MLD is optimal, but its complexity grows exponentially with the number of symbols detected. As a result, there are demands for near MLD schemes that provide similar performance with less complexity. In this paper, we consider the MU–MIMO SC‐FDMA communication and propose a low‐complexity and high‐performance turbo receiver for the systems. Some simulation examples for uplink scenario are given to demonstrate the effectiveness of the proposed scheme. Copyright © 2015 John Wiley & Sons, Ltd.
Applicability of the pre‐death grief concept to dementia family caregivers in Asia
Authors: Liew Tau Ming 
Published: November 2015

ObjectivePre‐death grief is prevalent among dementia family caregivers. When unaddressed, it produces adverse outcomes. With its research primarily conducted in Caucasians, its applicability to non‐Caucasians is uncertain. We explore the existence and the characteristics of pre‐death grief in a multi‐ethnic Asian population using an established pre‐death grief scale—Marwit–Meuser Caregiver Grief Inventory (MM‐CGI).MethodsSeventy‐two dementia family caregivers were recruited from a tertiary hospital. Existence of pre‐death grief was shown by its measurability on MM‐CGI, together with good internal consistency reliability and construct validity. Characteristics of pre‐death grief were explored through multivariate linear regression of MM‐CGI and by comparing MM‐CGI scores with those from the original US study using one‐sample T‐test.ResultsIn the Asian context, pre‐death grief was measurable in a reliable and valid manner. Risk factors of pre‐death grief included caring for patients with severe dementia, spousal relationship and secondary or below education. Influence of culture was palpable—Asians had more worries and felt isolation, and certain ethnicity showed more pre‐death grief.ConclusionsPre‐death grief is applicable even to the non‐Caucasian population. It bears much similarity to that in Caucasians. Yet, its expression is modified by culture. Clinicians working with non‐Caucasian populations need to be sensitive to its presence and to the influence of culture on its expression. © 2015 The Authors. International Journal of Geriatric Psychiatry published by John Wiley & Sons, Ltd.
Raster‐scanned intensity‐controlled carbon ion therapy for mucosal melanoma of the paranasal sinus
Authors: Mohr Angela , Chaudhri Naved , Hassel Jessica C. , Federspil Philippe A. , Vanoni Valentina , Debus Jürgen , Jensen Alexandra D. 
Published: November 2015

AbstractBackgroundThe purpose of this study was to evaluate the use of raster‐scanned intensity‐controlled carbon ion therapy (ICCT) in the treatment of mucosal melanoma of the paranasal sinus.MethodsPatients received combined intensity‐modulated radiotherapy (IMRT) plus carbon ion (C12). Records of 18 consecutive patients treated between 2009 and 2013 were analyzed retrospectively regarding toxicity (Common Terminology Criteria for Adverse Events, version 4), treatment response (Response Evaluation Criteria in Solid Tumors [RECIST]), and control/survival rates.ResultsMost patients had advanced disease (T4, 94%; gross residual disease, 78%). Median dose was 74 GyE (median boost volume = 157 mL). C12 treatments were planned as ICCT, no concurrent chemotherapy was administered. Grade III or higher late toxicity was not observed. Overall survival (OS), progression‐free survival (PFS), and locoregional control at 3 years were 16.2%, 0%, and 58.3%, respectively (median follow‐up, 18 months). Resection status did not impact locoregional control or survival rates.ConclusionICCT results in promising locoregional control at mild toxicity. OS is poor because of the occurrence of distant metastases; therefore, addition of systemic components to primary treatment should be investigated. © 2015 Wiley Periodicals, Head Neck 38: E1445–E1451, 2016
Prospective randomized controlled trial to compare 3‐dimensional conformal radiotherapy to intensity‐modulated radiotherapy in head and neck squamous cell carcinoma: Long‐term results
Authors: Ghosh–Laskar Sarbani , Yathiraj Prahlad H. , Dutta Debnarayana , Rangarajan Venkatesh , Purandare Nilendu , Gupta Tejpal , Budrukkar Ashwini , Murthy Vedang , Kannan Sadhana , Agarwal Jai Prakash 
Published: November 2015

AbstractBackgroundGrade ≥2 acute xerostomia between 3D conformal radiotherapy (RT) and intensity‐modulated radiotherapy (IMRT) was evaluated in patients with head and neck squamous cell carcinomas (HNSCCs) treated radically.MethodsBetween 2005 and 2007, 59 patients with HNSCC (T1–3, N0–2b) were randomized to IMRT or 3D‐RT. On RT, weekly xerostomia, dysphagia, dermatitis, and mucositis were graded by Radiation Therapy Oncology Group (RTOG) acute toxicity criteria. Patients underwent examination under anesthesia, positron emission tomography (PET)‐CT, and toxicity assessments per protocol (NCT00652613) thereafter.ResultsIncidence of grade ≥2 xerostomia at 8 weeks posttreatment was significantly lower with IMRT compared with 3D conformal RT (24% vs 53%; p = .024). At subsequent follow‐up, significantly fewer patients receiving IMRT had grade ≥2 xerostomia. Long‐term weight loss was higher in patients in the 3D conformal RT arm compared to IMRT (50% vs 21%; p = .038). Disease‐related outcomes between arms (median follow‐up, 70 months) were similar.ConclusionIMRT significantly reduces incidence of acute and late grade ≥2 xerostomia in patients with HNSCC. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1481–E1487, 2016