bluuebunny/crossref_metadata_2025 huggingface dataset:
Gas‐phase mass transfer characteristics in a counter airflow shear rotating packed bed
Authors: Liu Youzhi , Zhang Fangfang , Gu Deyin , Qi Guisheng , Jiao Weizhou , Chen Xiaoyan
Published: January 2016

The gas‐phase mass transfer characteristics in a counter airflow shear rotating packed bed (CAS‐RPB) were studied. The gas volumetric mass transfer coefficient (kyae) was characterized with the physical absorption system NH3‐H2O and the effective interfacial area (ae) was determined by the chemical absorption system CO2‐NaOH, and then the gas‐phase mass transfer coefficient (ky) was obtained. The gas‐phase mass transfer characteristics in the CAS‐RPB were compared with those in the rotating packed bed with split packing (SP‐RPB) under the same operating conditions. The experimental results indicated that the kyae, ae, and ky for counter‐rotation of adjacent packing rings in the CAS‐RPB and SP‐RPB were larger than those for co‐rotation, and the kyae, ae, and ky for counter/co‐rotation in the CAS‐RPB were respectively greater compared with those for counter/co‐rotation in the SP‐RPB. This confirmed that the CAS‐RPB can further intensify the gas‐phase mass transfer process compared to the SP‐RPB. Moreover, the correlative expressions for the kyae, ae, and ky in the CAS‐RPB and SP‐RPB were obtained and were in close agreement with the experimental results.
Determination of adsorption and kinetic parameters for methyl oleate (biodiesel) esterification reaction catalyzed by Amberlyst 15 resin
Authors: Ray Nillohit Mitra , Ray Ajay K.
Published: January 2016

In this work, adsorption equilibrium constants, dispersion coefficients, and kinetic parameters were determined for the reversible esterification reaction of oleic acid with methanol, producing methyl oleate (biodiesel) and water. The reaction was carried out at room temperature in the presence of Amberlyst 15 resin, which acts both as an adsorbent and catalyst in an HPLC column, which served as a packed bed reactor. A quasi‐homogenous kinetic model coupled with a linear adsorption isotherm was explored. The elution profiles of the reactant and products were experimentally monitored and then compared with a mathematical model. The adsorption and kinetic parameters were determined by minimizing the error between the experimentally obtained elution curves and the model‐predicted values using the genetic algorithm optimization technique. Further experiments were conducted under varying conditions to establish the validity of the obtained model parameters. It was also found that the system is not affected by internal and external mass transfer resistances. The mathematical model predicted the experimental outcome quite accurately.
Techno‐economic assessment of CO2 capture from aluminum smelter emissions using PZ activated AMP solutions
Authors: Lassagne Olivier , Iliuta Maria C. , Gosselin Louis , Désilets Martin
Published: January 2016

In order to reduce its greenhouse gas emissions without drastically changing currently‐used processes, the primary aluminum industry will need to consider capturing CO2 released in the electrolytic cells. In order to make the capture more economically attractive to the aluminum industry, the possibility of using a blended amine absorption solution which combines the advantages of two different amines (a fast reactivity from a cyclic polyamine, piperazine (PZ), and a high absorption capacity and low regeneration cost from a sterically‐hindered alkanolamine) is considered in this work. Specific to an aluminum plant, not only the costs and benefits of a CO2 capture facility are evaluated, but also the possibility and cost of coupling the capture process with a waste heat recovery strategy. A mixture of 0.08 g/g PZ and 0.32 g/g AMP appears to be the most appropriate, reducing the capital costs by 25 % and operating costs by 29 % compared to the use of MEA (monoethanolamine) solutions. The capture cost is evaluated to be 65.10 $/ton of CO2 avoided (without carbon tax). A thermal integration of the capture plant within the primary aluminum smelter could further reduce the cost to 57.57 $/ton of CO2 avoided, or equivalently, 69.56 $/ton of Al produced (without carbon tax).
H2S poisoning of NiAl2O4/Al2O3‐YSZ catalyst during methane dry reforming
Authors: Blanchard Jasmin , Achouri Ines , Abatzoglou Nicolas
Published: January 2016

The objective of this work was to test resistance to hydrogen sulphide (H2S) of a recently‐patented nickel‐aluminum (Ni‐Al) spinel on Al2O3/YSZ ceramic support in catalytic reforming of methane (CH4). Previous studies showed that the catalyst is efficient for both steam reforming of complex hydrocarbons (diesel) and dry reforming of CH4. In the latter case, carbon formation was avoided for 275 h with a carbon dioxide (CO2)/CH4 ratio of 1.2. Catalytic activity was monitored at various temperatures and H2S concentrations (780–850 °C and 1.28–237 μL/L (ppmv) H2S). All tests were conducted at atmospheric pressure in a differential reactor setup. The other experimental conditions were: molar ratio 1 CO2/1 CH4/0.1 H2O, catalyst mass of 0.3 g, and gas hourly space velocity of 7000–8000 mLSTP/(gcata · h). Helium was used as the carrier gas for H2S. The NiAl2O4/Al2O3‐YSZ catalyst was loaded with nickel (Ni) 0.05 g/g (5 mass%), the Al2O3/YSZ mass ratio was 1/1, and YSZ was Y2O3‐stabilized ZrO2 (Y2O3 0.07 g/g (7 mass%)). The results showed the fastest deactivation at low temperatures and the highest H2S concentration. Catalyst activity could be partially recovered by stopping the H2S feed, and entirely recovered by calcining it at 900 °C in air. Essentially, YSZ had no effect on catalyst resistance to the presence of H2S. The catalyst gave results comparable to a commercial catalyst tested and reported in the literature.
Rhizosphere Effect of Salix viminalis L. on Soil Enzyme Activity in a Wastewater Treatment Wetland
Authors: Swiontek Brzezinska Maria , Kalwasińska Agnieszka , Lalke‐Porczyk Elżbieta , Burkowska‐But Aleksandra , Jankiewicz Urszula
Published: January 2016

This paper presents the results how the root system of the common osier (Salix viminalis L.) affects the activity of selected extracellular enzymes (esterase, phosphatase, α‐glucosidase, β‐glucosidase, and leucine‐aminopeptidase) involved in the decomposition of organic matter in the constructed wetland, part of a wastewater treatment system. Soil samples from a zone affected by rhizosphere and a control sample were collected from three sampling sites located within the filter area: near the sewage inflow, in the middle of the plot, and at the end of the plot. The activities of the five extracellular enzymes were assayed by fluorescently labeled model substrates (4‐methylumbelliferyl and 7‐amido‐4‐methylcoumarin). Esterase activity was highest in the rhizosphere and control soil. The highest values of enzymatic activity were recorded in the rhizosphere soil at the wastewater inflow and decreased with increasing distance from that point.
Distribution of Legionella pneumophila in Thermal Pools
Authors: Walczak Maciej , Burkowska‐But Aleksandra , Swiontek Brzezinska Maria , Krawiec Arkadiusz
Published: January 2016

The study was aimed at assessing whether there is a risk of Legionella pneumophila in thermal pools used in balneotherapy and recreation. Water samples were collected from five thermal baths, supplied by thermal waters. The total number of bacteria was determined in the direct microscopic count under a fluorescence microscope. The numbers of bacteria from investigated phylogenetic groups (Legionella sp. and L. pneumophila) were estimated with the use of a fluorescence in situ hybridization method. The highest average total number of bacteria in the entire research cycle was recorded in old pools labeled OB1 and OB2. Bacteria belonging to the Legionella genus along with L. pneumophila were identified in all water samples collected from each bath. Moreover, a biofilm containing cells of L. pneumophila was identified in the collected water samples. The number of bacteria in water was dependent on the bath's age, the operation and the maintenance of the facilities. In old pools, with water exchanged periodically, the risk of L. pneumophila was higher; in new pools with a continual flow of water, lower. The results of this research showed no correlation between the number of Legionella and water temperature. Legionella pneumophila can successfully develop not only in fresh water bodies but in thermal baths as well. Still, it is uncertain whether the commonly applied culture method, developed for freshwater bodies, is also suitable for thermal baths.
Spatial Distribution and Toxic Potency of Trace Metals in Surface Sediments of the Seine Estuary (France)
Authors: Hamzeh Mariam , Ouddane Baghdad , Clérandeau Christelle , Cachot Jérôme
Published: January 2016

Due to very high anthropogenic pressures and urban waste discharge, the Seine estuary is still among the world's most polluted estuaries. The purpose of this work is to investigate the distribution of trace metals in surface sediments in order to assess to the contamination level, metal bioavailability, and ecotoxicological status. Five sites covering the salinity gradient of the estuary were chosen to evaluate the distribution and contamination level of trace metals in surface sediments. The results showed that trace metal concentration varied seasonally and spatially. Subsequently to assess the actual environmental toxicity of sediments, the Microtox® Bioassay using Vibrio fischeri was applied on aqueous extract of sediment. Calculated enrichment factors revealed that these sediments were highly polluted by mercury, cadmium, zinc, and lead. Most of pollution sources are localized upstream especially in Poses and Oissel, and the contamination levels decreased from Poses to north mudflat site. Positive values of toxicity index were detected in the upstream sediments indicating potential bioavailability of trace metals in the sediments. Sediment toxicity measured with the Microtox® test was positively correlated with toxicity index demonstrating the usefulness of the toxicity index for sediment quality assessment and possible implication of metals in sediment toxicity.
Treatment of muscle‐invasive bladder cancer: A systematic review
Authors: Chou Roger , Selph Shelley S. , Buckley David I. , Gustafson Katie S. , Griffin Jessica C. , Grusing Sara E. , Gore John L.
Published: January 2016

There is uncertainty regarding the use of bladder‐sparing alternatives to standard radical cystectomy, optimal lymph node dissection techniques, and optimal chemotherapeutic regimens. This study was conducted to systematically review the benefits and harms of bladder‐sparing therapies, lymph node dissection, and systemic chemotherapy for patients with clinically localized muscle‐invasive bladder cancer. Systematic literature searches of MEDLINE (from 1990 through October 2014), the Cochrane databases, reference lists, and the ClinicalTrials.gov Web site were performed. A total of 41 articles were selected for review. Bladder‐sparing therapies were found to be associated with worse survival compared with radical cystectomy, although the studies had serious methodological shortcomings, findings were inconsistent, and only a few studies evaluated currently recommended techniques. More extensive lymph node dissection might be more effective than less extensive dissection at improving survival and decreasing local disease recurrence, but there were methodological shortcomings and some inconsistency. Six randomized trials found cisplatin‐based combination neoadjuvant chemotherapy to be associated with a decreased mortality risk versus cystectomy alone. Four randomized trials found adjuvant chemotherapy to be associated with decreased mortality versus cystectomy alone, but none of these trials reported a statistically significant effect. There was insufficient evidence to determine optimal chemotherapeutic regimens. Cancer 2016;122:842–51. © 2016 American Cancer Society.
Anxiety, pain, and nausea during the treatment of standard‐risk childhood acute lymphoblastic leukemia: A prospective, longitudinal study from the Children's Oncology Group
Authors: Dupuis L. Lee , Lu Xiaomin , Mitchell Hannah‐Rose , Sung Lillian , Devidas Meenakshi , Mattano Leonard A. , Carroll William L. , Winick Naomi , Hunger Stephen P. , Maloney Kelly W. , Kadan‐Lottick Nina S.
Published: January 2016

BACKGROUND

This prospective study describes the procedure‐related anxiety, treatment‐related anxiety, pain, and nausea experienced by children with standard‐risk acute lymphoblastic leukemia (ALL) during the first year of treatment.

METHODS

This study was undertaken at 31 Children's Oncology Group (COG) sites. Eligible children who were 2 to 9.99 years old were enrolled in a COG trial for patients with newly diagnosed standard‐risk ALL from 2005 to 2009. Parents completed a demographic survey at the baseline and the Pediatric Quality of Life Inventory 3.0 Cancer Module (proxy version) and the General Functioning Scale of the Family Assessment Device 1, 6, and 12 months after the diagnosis. The association between patient‐related (age, sex, ethnicity, and treatment), parent‐related (marital status and education), and family‐related factors (functioning, income, and size) and symptom scores was evaluated.

RESULTS

The mean scores for procedure‐related anxiety, treatment‐related anxiety, and pain improved during the first year of treatment (P < .0389). The mean nausea score was poorer 6 months after the diagnosis in comparison with the other assessments (P = .0085). A younger age at diagnosis was associated with significantly worse procedure‐related anxiety (P = .004). An older age (P = .0002) and assignment to the intensified consolidation study arm (P = .02) were associated with significantly worse nausea.

CONCLUSIONS

Children with ALL experienced decreasing treatment‐related anxiety, procedure‐related anxiety, and pain during the first year of treatment. In comparison with scores at 1 and 12 months, nausea was worse 6 months after the diagnosis. Minimization of procedure‐related anxiety in younger children and improved nausea control in older children and those receiving more intensified treatment should be prioritized. Cancer 2016;122:1116–1125. © 2016 American Cancer Society
Cancer care cost trends in the United States: 1998 to 2012
Authors: Lee James A. , Roehrig Charles S. , Butto Erin Duggan
Published: January 2016

BACKGROUND

The authors examine trends in spending on cancer from 1998 through 2012, including cancer care costs, prevalence, and cases by payer, and discuss the results within the context of a prior analysis and recent health policy and programmatic changes.

METHODS

Condition‐specific distribution of expenditures from the Medical Expenditure Panel Survey, supplemented with results from the National Nursing Home Survey and other data sources, was used as the basis for allocating the Personal Health Care components of the National Health Expenditure Accounts among conditions.

RESULTS

Cancer care expenditures grew at an annualized rate of 2.9% from 1998 to 2012. The share of expenditures for hospital‐based care declined to a low of 48% during 2007 through 2009. Professional and clinical services' shares declined substantially between 2007 to 2009 and 2010 to 2012 when the hospital share increased. Treated prevalence decreased for all payers between the first and last study periods with the exception of private payers (11.2% increase). Out‐of‐pocket expenditures declined to 4.7%, whereas Medicare's share increased slightly. Medication expenditures increased, notably within retail and mail order settings.

CONCLUSIONS

The previous rapid growth of cancer prevalence and expenditures has now slowed, most remarkably since the 2007 recession. Out‐of‐pocket expenses for cancer treatment continue to decline, most recently reaching the lowest point in 25 years. In addition, the early effects of Affordable Care Act expansion can be observed in the decline of treated prevalence in the Medicaid population as the demographics of Medicaid enrollees change. Cancer 2016;122:1078–1084. © 2016 American Cancer Society
Electrochemistry of Layered Graphitic Carbon Nitride Synthesised from Various Precursors: Searching for Catalytic Effects
Authors: Yew Ying Teng , Lim Chee Shan , Eng Alex Yong Sheng , Oh Junghoon , Park Sungjin , Pumera Martin
Published: January 2016

Graphitic carbon nitride (g‐C3N4), synthesised by pyrolysis of different precursors (dicyandiamide, melamine and urea) under varying reaction conditions (air and nitrogen gas) is subjected to electrochemical studies for the elucidation of the inherent catalytic efficiency of the pristine material. Contrary to popular belief, pristine g‐C3N4 shows negligible, if any, enhancement in its electrochemical behaviour in this comprehensive study. Voltammetric analysis reveals g‐C3N4 to display similar catalytic efficiency to the unmodified glassy carbon electrode surface on which the bulk material was deposited. This highlights the non‐catalytic nature of the pristine material and challenges the feasibility of using g‐C3N4 as a heterogeneous catalyst to deliver numerous promised applications.
Hole‐Transporting Materials Based on Twisted Bimesitylenes for Stable Perovskite Solar Cells with High Efficiency
Authors: Lin Yan‐Duo , Ke Bo‐Yu , Lee Kun‐Mu , Chang Sheng Hsiung , Wang Kai‐Hung , Huang Shih‐Han , Wu Chun‐Guey , Chou Po‐Ting , Jhulki Samik , Moorthy Jarugu Narasimha , Chang Yuan Jay , Liau Kang‐Ling , Chung Hsin‐Cheng , Liu Ching‐Yang , Sun Shih‐Sheng , Chow Tahsin J.
Published: January 2016

A new class of hole‐transport materials (HTMs) based on the bimesitylene core designed for mesoporous perovskite solar cells is introduced. Devices fabricated using two of these derivatives yield higher open‐circuit voltage values than the commonly used spiro‐OMeTAD. Power conversion efficiency (PCE) values of up to 12.11 % are obtained in perovskite‐based devices using these new HTMs. The stability of the device made using the highest performing HTM (P1) is improved compared with spiro‐OMeTAD as evidenced through long‐term stability tests over 1000 h.
Multipotency of melanoblasts isolated from murine skin depends on the notch signal
Authors: Watanabe Natsuki , Motohashi Tsutomu , Nishioka Masahiro , Kawamura Norito , Hirobe Tomohisa , Kunisada Takahiro
Published: January 2016

Background: Melanoblasts (MBs), derived from neural crest cells, only differentiate into melanocytes (Ms) in vivo. We previously showed that MBs isolated from mouse skin were multipotent, generating neurons (Ns) and glial cells (Gs) together with Ms. Using Sox10‐IRES‐Venus mice and mouse embryonic stem cells, we investigated how MBs expressed their multipotency. Results: MBs generated colonies containing Ns, Gs, and Ms in the presence of ST2 stromal cells, but they generated only M colonies when incubated with keratinocytes or ST2 culture supernatant, thus showing that MBs required contact with ST2 stromal cells for expression of their multipotency. Notch signaling was shown to be one of the important cues for the maintenance and differentiation of MBs through cell–cell contact. When Notch signaling was inhibited, MBs mainly generated colonies that contained just one type of cells, Ns, Gs, or Ms; the number of colonies containing two or three types of cells markedly decreased even on ST2 stromal cells, showing restriction of their differentiation potency. Whereas when Notch signaling was activated, the number of colonies containing two or three types of cells increased, indicating that their multipotency had been maintained. Conclusions: Our results demonstrate that Notch signaling played novel roles in MB multipotency. Developmental Dynamics 245:460–471, 2016. © 2015 Wiley Periodicals, Inc.
Proper notch activity is necessary for the establishment of proximal cells and differentiation of intermediate, distal, and connecting tubule in Xenopus pronephros development
Authors: Katada Tomohisa , Sakurai Hiroyuki
Published: January 2016

Background: Notch signaling in pronephros development has been shown to regulate establishment of glomus and proximal tubule, but how Notch signal works on competency of pronephric anlagen during the generation of pronephric components remains to be understood. Results: We investigated how components of pronephros (glomus, proximal tubule, intermediate tubule, distal tubule, and connecting tubule) were generated in Xenopus embryos by timed overactivation and suppression of Notch signaling. Notch activation resulted in expansion of the glomus and disruption of the proximal tubule formation. Inhibition of Notch signaling reduced expression of wt1 and XSMP‐30. In addition, when Notch signaling was overactivated at stage 20 on, intermediate, distal, and connecting tubule markers, gremlin and clcnkb, were decreased while Notch down‐regulation increased gremlin and clcnkb. Similar changes were observed with segmental markers, cldn19, cldn14, and rhcg on activation or inhibition of Notch. Although Notch did not affect the expression of pan‐pronephric progenitor marker, pax2, its activation inhibited lumen formation in the pronephros. Conclusions: Notch signal is essential for glomus and proximal tubule development and inhibition of Notch is critical for the differentiation of the intermediate, distal, and connecting tubule. Developmental Dynamics 245:472–482, 2016. © 2015 Wiley Periodicals, Inc.
High‐Precision Sensorless Force Control by Mode Switching Controller for Positioning Devices with Contact Operation
Authors: MAEBASHI WATARU , ITO KAZUAKI , MATSUO KOHEI , IWASAKI MAKOTO
Published: January 2016

This paper presents an approach to high‐precision sensorless force control for positioning devices that engage in a contact operation. The sensorless force control is designed with a sliding mode controller and contact model that provide the required control specifications to compensate for the nonlinear spring characteristics of the contact mechanism. The effectiveness of the proposed control approach was verified through numerical simulations and experiments using a prototype.
Iron Loss Characteristics of Electrical Steel Sheet under Inverter Excitation by Power Semiconductor with Extremely Low On‐Voltage Property
Authors: ODAWARA SHUNYA , KAYAMORI DAISUKE , FUJISAKI KEISUKE
Published: January 2016

In this study, it is demonstrated that the iron loss from the SiC‐MOSFET, which represents a new power semiconductor with an extremely low on‐voltage for electric machine drives, is almost the same as that from an Si‐IGBT, which is a conventional power semiconductor. In order to evaluate the iron loss characteristics when an SiC device is used, two single‐phase pulse width modulation inverters were built and used for the excitation of a ring made up of electrical steel sheet. One of the inverter employed an SiC‐MOSFET, and the other inverter employed an Si‐IGBT. The iron losses for the two inverters are compared.
Estimation Prediction Interval of Solar Irradiance Based on Just‐in‐Time Modeling for Photovoltaic Output Prediction
Authors: YAMAZAKI TOMOHIDE , HOMMA HAYATO , WAKAO SHINJI , FUJIMOTO YU , HAYASHI YASUHIRO
Published: January 2016

Photovoltaic (PV) systems have recently attracted considerable attention in the context of environmental problems, antinuclear power movements, and energy problems. Therefore, the large‐scale introduction of PV systems is expected in the near future. But the connection of many PV systems to the power system leads to problems. For example, the system voltage often drifts from the norm when reverse power flows increase. Accordingly, optimal system operation is required in order to make maximum use of solar energy to the maximum by installing energy buffers such as storage batteries. In particular, in forecast information, knowledge of the reliability as well as the predicted solar irradiance is essential for effective operation. In this paper, we propose a way of estimating the prediction interval of solar irradiance as an index of reliability by using just‐in‐time modeling. We consider the accuracy of the prediction interval under many conditions and derive a high‐precision estimation method. In addition, we also discuss about the future subjects of study.
Three‐Phase to Single‐Phase Matrix Converter for Improvement of Three‐Phase Voltage Unbalance in Distribution System
Authors: MIZUTANI RYOTA , KOIZUMI HIROTAKA , HIROSE KENTARO , ISHIBASHI KAZUNARI
Published: January 2016

From the global environmental viewpoint, distributed power systems using renewable energy source, such as solar power, wind power, and water power, are attracting much attention. Photovoltaic (PV) systems using solar power have few resource constraints and can be installed easily on the roofs of houses. Therefore, PV systems have been and will be introduced widely. However, when many PV systems are installed in consumers, differences in installed PV capacity may cause load unbalances. In such a case, the difference in the line currents flowing along medium‐ and high‐voltage lines can be increased and three‐phase voltage unbalances may appear due to the line impedance. In this paper, a distribution transformer using a three‐phase to single‐phase matrix converter with an ac inductor is proposed to suppress three‐phase voltage unbalances. The ac inductor is used for compensation of single‐phase power pulsations under any load conditions and in either direction of power flow. The proposed method was verified by a simulation with MATLAB/Simulink. In this simulation, resistive loads and reactive loads were assumed as the loads in the low‐voltage line. Reverse power flow from PV systems is represented by a current source with a power factor of 1.0. The control strategy and simulation results are presented in this paper.
Pressure Rise due to SF6 Arcing and Energy Balance in a Closed Container
Authors: KOTARI MASASHI , TADOKORO TOMO , TANAKA SHIN‐ICHI , IWATA MIKIMASA , AMAKAWA TADASHI
Published: January 2016

From an environmental viewpoint, when carrying out internal arc tests on SF6‐insulated power equipment, it is necessary to prevent SF6 from being released into the atmosphere or to replace SF6 with air in accordance with IEC standards. However, the pressure rise and the thermal effect of the hot gas exhausted during arcing when testing in air are still considerably different from those for testing in SF6. Thus, it is necessary to propose a specific procedure to replace SF6 with air and to select appropriate parameters for the tests. Therefore, it is desirable to clarify the equivalent conditions causing these phenomena both experimentally and analytically. In this paper, we describe the effect of the charged gas pressure in a closed container on the pressure rise due to air and SF6 arcing and the ratio of the arc energy to the energy contributing to the internal pressure rise () from an experimental viewpoint. Additionally, to research the energy balance resulting from SF6 arcing in the container, the energy balance is discussed on the basis of chemical reactions, radiation, and the melting and vaporization of the electrodes. It is found that the maximum pressure rise increases for both gases upon increasing the gas pressure from 0.1 MPa to 0.4 MPa. Subsequently, good agreement with the energy balance was obtained under reasonable assumptions by taking account of the energy components related to the chemical reactions, radiation, and the melting and vaporization of the electrodes. The ratio of the radiation energy loss to the total consumption energy increased upon increasing the charged gas pressure.
Isolated Operation of Power System in Complex Housing Supplied by Battery Energy Storage System and Fuel Cells
Authors: SATO TAIHEI , ARAI JUNICHI , NAGAHIRA TOMOKI , SHINJI TAKAO , OGATA TAKAO , TSUKADA TATSUYA , YAMASHITA AKIRA
Published: January 2016

Fuel cells, as components of cogeneration systems and battery energy storage systems, can be used as power sources in an isolated power system in complex housing at times of blackout. This paper reports study results on such isolated power systems. Simulation models are developed and the results are compared with measured values of active power, reactive power, and voltage. Good agreement is obtained. In this analysis, it is found that there is a stability limit in such inverter power source operation. The stability limit is expressed by a short circuit power ratio that is similar to the one in conventional ac systems. Nonlinear load switching is also studied to demonstrate stable operation.
Defect‐Related Luminescence in ­Nitridoborate Nitride, Mg3Ga(BN2)N2
Authors: Dutczak Danuta , Wurst Kai Matthias , Ströbele Markus , Enseling David , Jüstel Thomas , Meyer H.‐Jürgen
Published: January 2016

The new nitridoborate nitride Mg3Ga(BN2)N2 was prepared by multilateral solid‐state metathesis reaction from MgCl2, GaN, Li3N, and Li3BN2 at high temperature. The crystal structure of Mg3Ga(BN2)N2 was refined from X‐ray powder diffraction patterns isotypically to Mg3Al(BN2)N2 with the space group R$\bar {3}$m no.166 [Z = 3, a = b = 3.4560(0) Å, c = 31.7924(2) Å]. The undoped and Eu2+‐doped Mg3Ga(BN2)N2 show orange‐red luminescence under UV excitation.
Mono‐, Di‐, and Polymeric Pyridino­ylhydrazone ZnII Complexes: Structure and Photoluminescent Properties
Authors: Borbone Fabio , Caruso Ugo , Concilio Simona , Nabha Shiran , Panunzi Barbara , Piotto Stefano , Shikler Rafi , Tuzi Angela
Published: January 2016

A series of zinc complexes with tridentate pyridinoylhydrazone ligands bearing two different end groups and coordinated pyridine molecules were synthesized and characterized. Crystal structures with mono‐, di‐, and polymeric arrangements were obtained, depending on the position of the pyridinoyl nitrogen atom. Direct involvement of the pyridinoyl moiety in the coordination to the metal was observed when the nitrogen was in the ortho or meta position. The meta derivatives led to 1D polymers with the same coordination environment, regardless of the bulkiness of the end group. In this case, unprecedented solid‐state photoluminescence quantum yields were recorded. In the ortho ligands, the further bidentate N,N site involving the pyridinoyl nitrogen atom was able to coordinate a further zinc acetate unit. Molecular and periodic calculations were performed within density functional theory (DFT) to rationalize the photophysical behavior. Excellent agreement between the theoretical and experimental absorptions was observed. The HOMOs and LUMOs of the complexes were investigated both in the solid state and in solution.
Solvent Influence on the Magnetic Properties of Iron(II) Spin‐Crossover Coordination Compounds with 4,4′‐Dipyridylethyne as Linker
Authors: Dankhoff Katja , Lochenie Charles , Puchtler Florian , Weber Birgit
Published: January 2016

New iron(II) coordination polymers with solvent‐dependent spin‐crossover behaviour have been synthesised by using an N2O2 Schiff base like ligand and 4,4′‐dipyridylethyne as the bridging axial ligand in different solvents. The effects of different solvents and preparation methods (temperature, concentration) on the magnetic properties have been investigated. Annealing the coordination polymers prepared by the same method but in different solvents led to the same compound exhibiting the same three‐step spin crossover independent of the magnetic properties of the solvated species. The X‐ray structures of the axial ligand, an iron(II) dimer and one of the iron(II) coordination polymers are discussed. Powder X‐ray diffraction analysis was additionally used for further comparison of the compounds.
Facile Synthesis of Cooperative Acid–Base Catalysts by Clicking Cysteine and Cysteamine on an Ethylene‐Bridged Periodic Mesoporous Organosilica
Authors: Ouwehand Judith , Lauwaert Jeroen , Esquivel Dolores , Hendrickx Kevin , Van Speybroeck Veronique , Thybaut Joris W. , Van Der Voort Pascal
Published: January 2016

A periodic mesoporous organosilica (PMO) that contains ethylene bridges was functionalized to obtain a series of cooperative acid–base catalysts. A straightforward, single‐step procedure was devised to immobilize cysteine and cysteamine on the support material by means of a photoinitiated thiol‐ene click reaction. Likewise, PMO materials capped with hexamethyldisilazane (HMDS) were used to support both compounds. This resulted in different materials in which the amine site was promoted by carboxylic acid groups, surface silanol groups, or both. The catalysts were tested in the aldol reaction of 4‐nitrobenzaldehyde and acetone. It was found that silanol groups have a stronger promoting effect on the amine than the carboxylic acid group. The highest turnover frequency (TOF) was obtained for an amine‐functionalized material that contained only silanol promoting sites. The loading of the active sites also had a significant effect on the activity of the catalysts, which was rationalized on the basis of a computational study.
Optimized Design of Pt‐Doped Bi2WO6 Nanoparticle Synthesis for Enhanced Photocatalytic Properties
Authors: Lavergne Marie‐Anne , Chanéac Corinne , Portehault David , Cassaignon Sophie , Durupthy Olivier
Published: January 2016

The preparation of photocatalytic heterostructures of platinum on Bi2WO6 nanoparticles by a wet reduction method is described in this report and compared with other preparation methods. The as‐obtained photocatalysts were characterized by XPS and TEM, the results of which confirmed the presence of solely zero‐valent metal nanoparticles on the surface of Bi2WO6. The photocatalytic activity of these heterostructures was evaluated by the degradation of Rhodamine B under blue light (λmax = 445 nm). The deposited noble metal nanoparticles were shown to significantly improve the photocatalytic performance of the bismuth‐based material under visible light. Both the preparation mode and the metal loading may impact on the efficiency. The observed photocatalytic enhancement has been attributed to an electron transfer from the semiconductor to the metal, which prevents fast electron/hole recombination. The electrons trapped in the metals may then participate in the multi‐electron reduction of O2.
Emissive Ruthenium–Bisdiimine Complexes with Chelated Thioether Donors
Authors: Wallenstein Joachim Hedberg , Sundberg Jonas , McKenzie Christine J. , Abrahamsson Maria
Published: January 2016

The photophysical properties of ruthenium(II) complexes of bidentate 2‐[(alkylthio)methyl]pyridine (N,S) ligands have been systematically investigated. The co‐ligands in the heteroleptic complexes were diimines (N,N ligands, e.g., bpy, phen) or tripodal tetradentate tris(2‐pyridylmethyl)amine (tpa). Their X‐ray structures revealed little variation in the Ru–S (2.31–2.33 Å) and Ru–N (2.06–2.11 Å) bond lengths. Despite this, considerable variation can be observed in the electrochemistry and spectroscopy measurements. The presence of the thioether sulfur donor results in a shift to a more positive potential of the Ru2+/Ru3+ process, and the absorption maxima are consequently blueshifted in [Ru(N,N)2(N,S)]2+ complexes compared with the [Ru(N,N)3]2+ analogues. The [Ru(N,N)2(N,S)]2+ complexes display strong room‐temperature emission from 3MLCT states, governed by the N,N donors. This is corroborated by low‐temperature steady‐state emission studies, which revealed typical 3MLCT emission profiles and excited‐state lifetimes of around 5–10 µs.
Fluorescence Quenching in BODIPYs Having Ir‐ and Rh‐Tethered Complexes
Authors: Chu Gong M. , Fernández Israel , Guerrero‐Martínez Andrés , Ramírez de Arellano Carmen , Sierra Miguel A.
Published: January 2016

The effect of Rh‐ and Ir‐centers on the optical properties of the BODIPY core has been studied. To this end, novel metal complexes tethered to BODIPY have been prepared through an easy and versatile procedure using N‐directed C–H activation reactions. The organometallic moiety has a tremendous influence on the emissive properties of the BODIPY fragment. A photoinduced electron transfer (PET) mechanism is suggested to be the main mechanism responsible for the suppression of the BODIPY fluorescence emission in the newly formed dyads. The efficiency of the PET depends on both the distance between the chromophores in the dyad and the nature of the transition metal (Rh vs. Ir).
Development and characterization of solid lipid microparticles containing vitamin C for topical and cosmetic use
Authors: Gu Chengyu , Hu Caibiao , Ma Chaolong , Fang Qiao , Xing Tingkang , Xia Qiang
Published: January 2016

Solid lipid microparticles (SLMs), combined with the advantages of double emulsions (W/O/W) and water‐in‐oil micro emulsions, are developed for transdermal administration. A modified one‐step emulsification method was introduced, which made the industrial production of SLMs easier. Variables involved in preparation that may affect the solubility, stability, and entrapment efficiency of SLMs were investigated. With vitamin C as a model active, the advantages of SLMs in transdermal administration were studied further. Vitamin C, encapsulated by SLMs, exhibited an enhanced storage stability up to 1 month under 25°C and a sustained releasing profile over 24 h. Furthermore, the SLMs was very helpful in delivering vitamin C molecules into skin through stratum corneum. The result showed 5.52‐fold (p < 0.05) increased absorption of vitamin C, compared to the vitamin C solution. These studies demonstrate that SLMs could be a promising method for facilitating transdermal penetration of active ingredients with high solubility and low permeability.

Practical applications: SLMs could be used as a drug delivery system for hydrophilic active ingredients with low permeability. Experiments have shown better stability and skin permeability of vitamin C incorporated in SLMs when compared with pure vitamin C. Furthermore, the method of producing SLMs is simple and can be realized in a way of industrial production. Since SLMs can dissolve in water, SLMs can be directly used on wet skin with excellent skin‐touch feel. As a result, SLMs could be a practical delivery system for hydrophilic compounds with low permeability in many applications such as pharmaceuticals and cosmetics.

Solid lipid microparticles (SLMs), combined with the advantages of double emulsions (W/O/W) and water‐in‐oil micro emulsions, are developed for transdermal administration. A modified one‐step emulsification method was introduced, which made the industrial production of SLMs easier. With vitamin C as a model active, the advantages of SLMs in transdermal administration were studied further. Vitamin C, encapsulated by SLMs, showed an enhanced storage stability up to 1 month and a sustained releasing profile over 24 h. Furthermore, the SLMs can facilitate skin's absorption of VC with pig as the model animal. These studies demonstrate that SLMs can be a promising method for facilitating transdermal penetration of active ingredients with high solubility and low permeability.
Acoustic properties of crystallized fat: Relation between polymorphic form, microstructure, fracturing behavior, and sound intensity
Authors: Gregersen Sandra Beyer , Povey Malcolm J. W. , Andersen Morten Daugaard , Hammershøj Marianne , Rappolt Michael , Sadeghpour Amin , Wiking Lars
Published: January 2016

This study demonstrates a link between the fat crystal network, fracturing behavior, and sound emission upon breakage. SOS, PSO, PPO, and POP rich fats were characterized by SAXS/WAXS and confocal laser scanning microscopy. Simultaneous texture and acoustic analysis was conducted by the use of a texture analyzer connected with an acoustic envelope detector and augmented by a broad band microphone combined with a digital sampling oscilloscope. Results shows a high correlation between negative values of the 2nd derivative of force curves, providing a measure of the energy release, and the sound intensity (r = 0.89, p < 0.05). No relation between acoustic properties and polymorphic behavior, crystal size, or crystal morphology was found. All fats crystallized into a β′ form within 1 day of storage. Subsequently, only the PPO and POP rich fats transformed into the β form (2–4 wk). Evaluation of the relative strength of intra‐ and interparticle links within the fat crystal network, indicate an important role of inter‐particle links for the sound intensity, whereas intra‐particle links were of less importance. It is hypothesized that strong interparticle links provide a strong rigid structure resulting in build‐up of energy during compression and a fast energy release upon breakage accompanied by sound emission.

Practical applications: Results from this study provide important knowledge on acoustic properties of fat which can contribute to ensuring a suitable snap, in terms of a high intense sound upon breakage, of chocolate and confectionery products.

Acoustic properties of fats are important for the snap of chocolate and confectionery products. This study demonstrates how the breakage sound intensity is significantly correlated with the negative part of the second derivate of force curves, which can be related to a rigid structure due to strong intraparticle links.
One‐Pot Synthesis of Benzopyran‐4‐ones with Cancer Preventive and Therapeutic Potential
Authors: Talhi Oualid , Brodziak‐Jarosz Lidia , Panning Jana , Orlikova Barbora , Zwergel Clemens , Tzanova Tzvetomira , Philippot Stéphanie , Pinto Diana C. G. A. , Paz Filipe A. Almeida , Gerhäuser Clarissa , Dick Tobias P. , Jacob Claus , Diederich Marc , Bagrel Denyse , Kirsch Gilbert , Silva Artur M. S.
Published: January 2016

A one‐pot synthesis of novel benzopyran‐4‐ones is described. In a tandem reaction, organobase‐catalysed Michael addition of R1COCH2COR2 on chromone‐3‐carboxylic acid led to decarboxylation and pyran‐4‐one ring opening of the latter. This was followed by chromone‐ and/or chromanone ring closure of the resulting Michael adducts when R1 is an ortho‐hydroxyaryl group. Antioxidant testing of 14 derivatives identified strong antiradical properties of chromanones 3o–r (2.1–3.1 µmol Trolox equiv./µmol compound in the DPPH assay). Chromanones 3p and 3r and 2‐styrylchromone 3k were also most potent in inducing the cytoprotective Keap1‐Nrf2 signalling pathway in a reporter gene assay (fivefold induction at concentrations <3 µM). Of the seven compounds evaluated for antiproliferative activities, 3k and 3r were the most active, inhibiting leukaemia K562 cell proliferation by 50 % after 72 h at concentrations of 4.5 and 7.9 µM, whereas normal peripheral blood mononuclear cells were not affected.
Double π‐Bond Isomerization/Friedel–Crafts Reaction Involving γ‐­Amidocronates: Access to γ‐Aryl/Heteroaryl GABA Scaffolds and Dihydropyrido[1,2‐a]indoles
Authors: Srivastava Anvita , Samanta Sampak
Published: January 2016

A series of pharmacologically attractive γ‐indolyl/furyl/aryl‐substituted γ‐amino esters/γ‐aminoketones were obtained in good to high combined yields by π‐bond isomerization of N‐protected γ‐aminocrotonates/γ‐aminocrotonophenones in the presence of triethylamine, followed by tandem Friedel–Crafts alkylation involving several indole/furan/arene derivatives and the resultant N‐protected enamines at room temperature by using B(C6F5)3 (5 mol‐%) as an efficient Lewis acid catalyst. Moreover, the easy synthesis of the important class of 8,9‐dihydropyrido[1,2‐a]indole scaffolds was realized by this unique procedure. Thus, a simple, convenient, and metal‐free‐based protocol may provide an alternative powerful synthetic route for heteroarylation/arylation at the γ positions of GABA derivatives in a practical manner.
4‐Heterosubstituted Cyclopentenone Antiviral Compounds: Synthesis, Mechanism, and Antiviral Evaluation
Authors: Mantione Daniele , Aizpuru Olatz Olaizola , Memeo Misal Giuseppe , Bovio Bruna , Quadrelli Paolo
Published: January 2016

Racemic 4‐oxocyclopent‐2‐en‐1‐yl acetate was used in a short synthesis of nucleoside analogues with pyrimidine and purine heterobases. The protocol is based on a typical nucleophilic substitution process. Uracil, thymine, 6‐chloropurine, and some adenines gave the expected 4‐heterosubstituted products along with the isomeric 2‐heterosubstituted compounds as minor components. Samples of selected products were evaluated for their antiviral activity in a primary screening against a variety of viruses belonging to different classes. One of the compounds was found to be highly active against human papilloma virus (HPV).
A Modular Approach to the Asymmetric Synthesis of Cytisine
Authors: Struth Felix R. , Hirschhäuser Christoph
Published: January 2016

The asymmetric synthesis of (+)‐ and (–)‐cytisine starts with Matteson homologations for the construction of a chiral C3‐building block. Conversion of the C3‐building block into a dihydropyridone is achieved by straightforward functional group interconversions and ring closing metathesis. After bromination, this central building block was diastereospecifically converted into cytisine in five steps.
Azide–Enolate 1,3‐Dipolar Cycloaddition as an Efficient Approach for the Synthesis of 1,5‐Disubstituted 1,2,3‐Triazoles from Alkyl/Aryl Azides and β‐Ketophosphonates
Authors: González‐Calderón Davir , Fuentes‐Benítes Aydeé , Díaz‐Torres Eduardo , González‐González Carlos A. , González‐Romero Carlos
Published: January 2016

A simple procedure to prepare 1,5‐disubstituted 1,2,3‐triazoles efficiently from alkyl/aryl azides and β‐ketophosphonates in the presence of KOH by an azide–enolate 1,3‐dipolar cycloaddition in good yields was developed.
Bridging Chiral Calix[4]arenes: Description, Optical Resolution, and Absolute Configuration Determination
Authors: An Feng‐Jing , Xu Wen‐Qiang , Zheng Shuang , Ma Shi‐Kun , Li Shao‐Yong , Wang Run‐Ling , Liu Jun‐Min
Published: January 2016

A new chiral calix[4]arene constructed from asymmetric substitution on bridging methylenes, phenyl rings, and (or) oxygen atoms was tentatively named as “bridging chiral” calix[4]arene that have point chirality on its substituted bridging methylene. A new approach to enantiopure bridging chiral calix[4]arenes through optical resolution is presented for the first time. As a result, a pair of enantiopure bridging chiral calix[4]arene carboxylic acids monobridge‐substituted with an equatorial N,N′‐dimethylformamidyl group (4a and 4b) were easily prepared by the optical resolution of their racemate with chiral auxiliary (S)‐Binol. The absolute configurations of the enantiomers were determined by X‐ray crystallographic analysis.
An Efficient and Tunable Route to Bis(1,2,3‐triazol‐1‐yl)methane‐Based Nitrogen Compounds
Authors: Castro‐Osma José A. , Lara‐Sanchez Agustín , Otero Antonio , Rodríguez Ana M. , de la Torre María C. , Sierra Miguel A.
Published: January 2016

A new and easy route to prepare “a la carte” bis(1,2,3‐triazol‐1‐yl)methane compounds, namely bmtzm (1), bptzm (2), bttzm (3), bmtzpm (4), bptzpm (5), bttzpm (6), bmtzom (7), bptzom (8) and bttzom (9), with different functional groups is reported. The compounds were prepared by reaction between readily accessible alkynes and geminal diazides in a double Cu‐catalyzed azide‐alkyne cycloaddition (CuAAC) reaction. These materials were used as starting materials for the synthesis of more elaborate compounds. Thus, the preparation of new bis(1,2,3‐triazol‐1‐yl)methane‐based heteroscorpionate neutral precursors pbptztamH (10), pbttztamH (11), (S)‐mbptzamH (12) and (S)‐mbttzamH (13) and a dinuclear zinc complex, [Zn{pbptztam}Et]2 (14), was achieved. The structures of the compounds were determined by spectroscopic methods, and the X‐ray crystal structures of compounds 2, 3, 7, 8, 9 and 14 were established.
An Efficient Approach to the Total Synthesis of Ammosamide B
Authors: Yang Sheng‐Wei , Wang Chun‐Meng , Tang Kai‐Xiang , Wang Jin‐Xin , Sun Li‐Ping
Published: January 2016

A new approach for the total synthesis of ammosamide B was realized. The strategy is based on an intermolecular Pd‐catalyzed N‐arylation of 4‐chloro‐1‐methylindoline‐2,3‐dione (2), which enables construction of the key pyrroloquinoline skeleton precursor 6 within three steps in an overall yield of 80 %. The ammosamide B total synthesis is achieved in 12 simple transformations by starting from a commercially available starting material and proceeds with an overall yield of 23 %. Additionally, key precursor 6 represents an important intermediate in the synthesis of other pyrroloquinoline‐containing natural products.