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Background: Typhonium blumei Nicolson & Sivadasan (Araceae) is a traditional Chinese medicinal herb possessing detumescent, detoxifying, and anti-inflammatory activities. It is used in Taiwan as a folk medicine to treat cancer and inflammatory diseases. Typhonium blumei is usually not distinguished from Typhonium roxburghii Schott and they are commonly used interchangeably.Purpose: To evaluate and compare the anti-allergic and anti-inflammatory properties of T. blumei and T. roxburghii, their composition profiles and molecular basis of the anti-allergic effect.Methods: The methanolic plant extracts were partitioned with different solvents to obtain the nonpolar fractions. The anti-allergic activity of the nonpolar fractions was assessed by A23187- and antigen-induced degranulation assays using RBL-2H3 mast cells. Several molecular targets were investigated: FcεRI receptor expression by flow cytometry, calcium influx by live cells imaging fluorescent microscopy, cytokines mRNA expression by RT-PCR, and protein expression by Western blotting. The anti-inflammatory activity was evaluated using superoxide anion and elastase release assays in human neutrophils. TLC, NMR and GC-MS analyses were conducted to evaluate the chemical composition of the fractions.Results: The nonpolar fractions of both Typhonium species showed potent inhibitory activity in A23187-induced degranulation assay in RBL-2H3 cells. They also inhibited superoxide production and elastase release in human neutrophils. T. blumei nonpolar fractions inhibited antigen-induced β-hexosaminidase and histamine release. The nonpolar fractions of T. blumei significantly inhibited calcium influx upon activation with either A23187 or an antigen. The fractions did not affect FcεRI receptor expression, mRNA level of IL-4 and MCP-1 cytokine production or MAPK proteins expression, but did suppress the calcium signaling pathway via PI3K/PLCγ2. The active fractions were rich in fatty acids with palmitic, linoleic and α-linolenic acids identified as the major fatty acids in both plants. The content of omega-3 unsaturated fatty acids was higher in T. roxburghii nonpolar fractions compared to T. blumei.Conclusion: Both species possess potent anti-allergic and anti-inflammatory activities. The inhibition of degranulation in mast cells was attributed to calcium influx modulation. The obtained results support the traditional use of T. blumei in the treatment of inflammatory diseases as well as its substitution with T. roxburghii. [ABSTRACT FROM AUTHOR]

In this work microwave and reflux-assisted transesterification of triolein in methanol was carried out with alkali-loaded low-Al Zeolite Beta as catalyst. The results show that the alkali-treated Zeolite Beta can effectively catalyze transesterification reaction of triglycerides to produce fatty acid ethyl esters (biodiesel), if Zeolite Beta has been properly modified with the alkali ion-exchange process. As a result, the final conversion yield over 90% could be obtained within an hour of reflux reaction. However, the durability of this Na-modified Zeolite Beta still has much room to be improved. In this work, this inferior catalytic durability is overcome by using the low-Al Zeolite Beta with a smaller particle size near 0.5 μm. Consequently, for at least eight cycles, cyclic tests of these zeolite catalysts do not result in any significant decrease in catalysis in transesterification reaction. It is inferred that alkali cations existing in defect-sites of low-Al Zeolite Beta can be supplied to the surface of the catalysts during transesterification and enhance the catalysis. [ABSTRACT FROM AUTHOR]

Hydrogen, one of environmentally benign energies, has attracting more and more attention. Out of many hydrogen storage systems, chemical hydrides not only have a high hydrogen storage capacity, but also produce ultrapure hydrogen in presence of adequate catalysts at room temperature. Among many chemical hydrides, ammonia borane (NH 3 BH 3 ) is one of the promising candidates because its intrinsic hydrogen content is as high as 19.6 wt%. Moreover, the spent products of ammonia borane are non-flammable and rarely toxic. The chemical hydride fuel system was prepared by pulverizing ammonia borane and Ni-Co/r-GO catalysts in a high-energy ball mill. The hydrogen was produced from catalyzed hydrolysis reaction of ammonia borane composite initiated with limited amount of water. Variable parameters such as the amount of water dosage and loading of catalysts will be discussed in this study. [ABSTRACT FROM AUTHOR]

In this work, biodiesel production from catalyzed transesterification of triglycerides with excess methanol was studied by using ion-exchanged Zeolite Beta and MCM-22 as heterogeneous catalysts. Zeolite Beta and MCM-22 were synthesized with hydrothermal processes and, subsequently, modified by ion-exchanged with alkali ions. These as -obtained zeolite catalysts could yield a high conversion of triglycerides to biodiesel. The conversion efficiency was largely affected by crystallinity and frameworks of zeolite support, pH value of alkali ion-exchange solutions and alkali loadings onto the zeolite support. Furthermore, the effects of the duration of the sodium ion-exchange process on the final conversion efficiency of triolein to biodiesel, both the as-prepared Zeolite MCM-22 and Zeolite Beta catalysts were used. The effect of the duration of the sodium ion-exchange process is insignificant in transesterification using Na-ion-exchanged Zeolite MCM-22 catalysts from 0.5 to 4 h. In contrast, the conversion efficiency of triolein to biodiesel reached ca. 95% in 0.5 hours of transesterification using Zeolite Beta ion-exchanged with 3 mmol-eq. Na + /g cat for 0.5 hours. [ABSTRACT FROM AUTHOR]

Biodiesel production from transesterification of vegetable oils in excess methanol was performed by using as-prepared catalyst from low-cost kaolin clay. This effective heterogeneous catalyst was successfully prepared from natural kaolin firstly by dehydroxylation at 800°C for 10h and, subsequently, by NaOH-activation hydrothermally at 90°C for 24h and calcined again at 500°C for 6h. The as-obtained catalytic material was characterized with instruments, including FT-IR, XRD, SEM, and porosimeter (BET/BJH analysis). The as-prepared catalyst was advantageous not only for its easy preparation, but also for its cost-efficiency and superior catalysis in transesterification of vegetable oils in excess methanol to produce fatty acid methyl esters (FAMEs). Conversion efficiencies of soybean and palm oils to biodiesel over the as-prepared catalysts reached 97.0±3.0% and 95.4±3.7%, respectively, under optimal conditions. Activation energies of transesterification reactions of soybean and palm oils in excess methanol using these catalysts are 14.09kJ/mol and 48.87kJ/mol, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Grapeseed extract (GSE) is a rich source of natural phenolic compounds and possesses various pharmacological activities, including antioxidant, anticarcinogenic and anti-inflammatory properties. However, effects of GSE on immunoglobulin (Ig) E-mediated allergic responses still remain elusive. In the present study, the effects of GSE on activation and degranulation of RBL-2H3 mast cells were investigated. GSE pretreatments (20–100μg/ml) reduced IgE-antigen mediated release of β-hexosaminidase and histamine in RBL-2H3 cells. Additionally, GSE reversibly inhibited expression of FcεRI on RBL-2H3 cells. GSE treatments caused a significant elevation of intracellular cAMP levels, whereas the Ca2+ influx upon antigen stimulation was inhibited. Suppression on FcεRI expression together with decreased calcium uptake and increased cAMP level might be involved in attenuated degranulation of mast cells by GSE treatment. Our results suggest a possible pharmaceutical application of GSE in treating type I allergic diseases. [Copyright &y& Elsevier]

Abstract: Solid-state NaBH4/Ru-based catalyst composites have been fabricated for hydrogen generation through a high-energy ball-milling process, providing uniform dispersion of resin-supported Ru3+ catalysts among pulverized NaBH4 (SBH) particles, so as to increase the contacts of SBH with active catalytic sites. Consequently, the gravimetric hydrogen storage capacity as high as 7.3wt% could be achieved by utilizing water as a limiting reagent to overcome the issue of deactivated catalysts whose active sites are often blocked by precipitates caused by limited NaBO2 solubility occurring in conventional aqueous SBH systems for hydrogen productions. Products of hydrolyzed SBH that greatly influence the gravimetric H2 storage capacity are found to be most likely NaBO2·2H2O and NaBO2·4H2O from SBH/H2O reacting systems with initial weight ratios, SBH/H2O=1/2 and 1/10, respectively, according to the TGA and XRD analyses. [Copyright &y& Elsevier]

Abstract: A fast and simple fabrication process, viz. a wet-chemical reduction process, was utilized for preparation of a cobalt-based catalyst to be used for hydrogen generation from alkaline NaBH4 solution. Characteristics of this cobalt-based catalyst were carried out by using various instruments, such as SEM/EDS, XPS, ICP, VSM, BET and TGA. The surface chemistry of the obtained catalyst is mainly cobalt oxides, not cobalt borides. Ferromagnetic property of the cobalt-based catalyst makes it convenient for being recycled from spent NaBH4 solution. The rate of hydrogen generation from catalyzed hydrolysis of alkaline NaBH4 solution was determined as a function of temperature, NaBH4 concentration, and NaOH concentration in the presence of prepared catalysts. In general, stable generation rate of highly pure hydrogen near 200mLmin−1 g−1 was achieved in 100mL of 5wt% NaBH4 solution containing 5wt% NaOH solution and 200mg of Co/IR-120 catalyst, in which no temperature runoff was observed during the course of hydrogen production. The activation energy of NaBH4 hydrolysis reaction was found at 66.67kJmol−1, which was comparable with others reported in the open literatures. [Copyright &y& Elsevier]

Abstract: Magnetic nickel–ruthenium based catalysts on resin beads for hydrogen generation from alkaline NaBH4 solutions were synthesized with combined methods of chemical reduction and electroless deposition. Factors, such as solution temperature, NaBH4 loadings, and NaOH concentration, on performance of these catalysts on hydrogen production from alkaline NaBH4 solutions were investigated. Furthermore, characteristics of these nickel–ruthenium based catalysts were carried out by using various instruments, such as SEM/EDS, XPS, SQUID VSM and BET. These catalysts can be easily recycled from spent NaBH4 solution with permanent magnets owing to their intrinsic soft ferromagnetism and, therefore, reducing the operation cost of the hydrogen generation process. A rate of hydrogen evolution as high as ca. 400mL min−1 g−1 could be reached at 35°C in 10wt% NaBH4 solution containing 5wt% NaOH using Ni–Ru/50WX8 catalysts. Activation energy of hydrogen generation using such catalysts is estimated at 52.73kJ mol−1. [Copyright &y& Elsevier]

Abstract: Biodegradation of three nonionic surfactants, Tergitol 15-S-X (X =7, 9 and 12), and their effects on the biodegradation of phenanthrene by marine bacteria, Neptunomonas naphthovorans, were studied. The experimental outcomes could be fit well with the first-order biodegradation kinetics model. It was observed that the biodegradability of these surfactants decreased with an increase in the chain length of the hydrophilic moiety of the surfactant. When surfactant concentrations initially present were less than 250mgcarbon/L, biodegradability of Tergitol 15-S-X surfactants is around 0.3. Reduced biodegradability of Tergitol 15-S-7 and Tergitol 15-S-9 was observed when their concentrations initially present were increased to 322 and 371mgcarbon/L, respectively. In general, biodegradation of phenanthrene was enhanced with increasing solubilization of phenanthrene by these surfactants. However, with the same initial concentration of phenanthrene, biodegradability of phenanthrene was found to decrease with an increase in surfactant concentration. For these three surfactants, more than 80% of the phenanthrene was degraded when surfactant concentrations initially present were 200mg/L. However, less than 30% of phenanthrene could be degraded, if initial surfactant concentrations were increased to 1000mg/L. Interestingly, the concurrent biodegradation of the surfactants reduced their effective concentrations for micelle formation and, hence, contribute to the higher bioavailability of phenanthrene by gradually releasing phenanthrene molecules into the aqueous phase. [Copyright &y& Elsevier]

Abstract: Effect of nonionic surfactants on the performance of the cloud-point extraction (CPE) processes in preconcentrating trace amount of polycyclic aromatic hydrocarbons (PAHs), consisting of two to five fused rings, from aqueous solution at 25°C was studied. Three biodegradable nonionic surfactants with molecular similarity were employed. Cloud-point temperatures (CPTs) of these micellar solutions were regulated and reduced enough with addition of sodium sulfate and sodium phosphate, so that the CPE process could be facilitated at 25°C. Furthermore, quadratic equations in additive concentration are found to fit the CPTs of these micellar solutions well. It is observed that the preconcentration factor could be enhanced either by increasing the salt concentration or by decreasing the initial surfactant concentration present in the micellar solution. With CPTs regulated at around 15 and 18°C with addition of Na2SO4 and Na3PO4, preconcentration factors in between 30 and 45 obtained from 1wt% micellar solutions of these three surfactants appear in the order of Tergitol 15-S-9>Neodol 25-7>Tergitol 15-S-7, coincidently with the hydrophilicity order of surfactants. The average preconcentration factor was empirically fitted well as a simple power-law function of surfactant concentration used in the CPE process. The obtained empirical power-law indices are close to negative unity. [Copyright &y& Elsevier]

Abstract: The rheological characteristics of the wastewater sludge were investigated by using a Haake Rheostress RS 75 rheometer. The stress–sweep experiments and the small-amplitude-oscillatory-shearing (SAOS) tests were conducted. The stress–sweep measurements demonstrate that addition of polymer coagulants to sludge samples could significantly influence the corresponding complex shear modulus G*. Furthermore, the SAOS tests indicate that the sludge samples treated with polymer coagulants will form more rigid structures. The original sludge samples mostly show typical viscoelastic liquid-like behavior. However, the solid-like behaviors were always observed in the samples treated with polymers. [Copyright &y& Elsevier]

Abstract: Separation of CO2 from a gas stream, using a hollow fiber membrane contactor, is a promising alternative to conventional techniques such as column absorption. The major advantages of the membrane absorption are the larger interfacial area, a better device-modularity and more operational flexibility. The factors that impact the efficiency and performance of the absorption process using a hollow fiber membrane contactor, as well as the evaluation of model parameters are reviewed in this paper. Strategies on further development of this process are also proposed. [Copyright &y& Elsevier]

Resist trimming process using CF4/O2 has been developed for sub-0.1 μm polysilicon gate patterning using conventional 248-nm lithography. This process allows the successful fabrication of 80-nm MOS devices. The trimming step is performed in situ as part of the polysilicon gate etching process. The effects of process parameters on trim-rate, trim-rate-nonuniformity and microloading effect are investigated using design-of-experiment. The trim-rate is affected very significantly by the over-etch percentage and O2 gas flow. Bias voltage is of much importance in the linewidth control and the microloading effect, but less significant on trim-rate. The trim-rate increases with increasing RF source power and reactor pressure but decreases with higher bias voltage, indicating that the trimming process is dominated by the neutral reactant species. An optimized recipe has been developed and is proven to be reproducible. The optimum shrinking rate of resist critical dimension is 1.4 nm/s and the trim-rate-nonuniformity σ is about 1.7% of the average trim-rate. Good sidewall profiles of the resist and polysilicon gate are maintained. Transistors having near 80 nm gate length are fabricated successfully by trimming the photoresist having the developed inspection critical dimension (DICD) at 122.6 nm with σ=2.7 nm. The final inspection critical dimension (FICD) and the effective channel length (Leff) of the aforementioned transistors are 78.5 nm with σ=2.1 nm and 79.7 nm with σ=3.2 nm. Both p-channel and n-channel devices show tight saturation current (Idsat) control with σ less than 5% of the mean value. [Copyright &y& Elsevier]

Kinetics of hydrotreating reaction of palmitic acid in H 2 at 35 bar and 300 °C [Display omitted] • Ni/ZSM-5 and Ni-Mo/ZSM-5 successfully prepared by incipient wetness impregnation. • Hydrodeoxygenation (HDO) of palmitic acid performed at T = 300 °C and P H2 = 35 bar. • Conversion of palmitic acid could reach ca. 99% after 4 h of HDO reaction at 300 °C. • Normal and branched paraffins (C > 12) are main HDO products of palmitic acid. • Molybdenum can effectively promote the catalytic activity of Ni in HDO reaction. In this study, Ni and Ni/Mo catalysts supported on zeolite ZSM-5, aka Ni/ZSM-5 and Ni-Mo(R)/ZSM-5, were successfully prepared by the incipient wetness impregnation method to hydrotreat heterogeneously the palmitic acid with an aim for the production of green diesel. Various instruments, such as XRD, SEM, BET, XPS, NH 3 -TPD and H 2 -TPR, were employed to characterize these catalysts. The hydrodeoxygenation (HDO) reaction of palmitic acid was carried out in an autoclave at 300 °C with an initial pressure of hydrogen at 35 bar. With Ni-Mo(R)/ZSM-5 catalysts priorly reduced in H 2 at 500 °C, the conversion of palmitic acid could reach near 99% after 4 h of HDO reaction at 300 °C. Furthermore, a significant portion of isomerized paraffins appeared in the product, as revealed by GC–MS. That is, both hydrodeoxygenation and hydroisomerization reactions took place conjointly on palmitic acid with Ni-Mo(R)/ZSM-5 catalysts. [ABSTRACT FROM AUTHOR]

Abstract In this study, natural diatomaceous earth was utilized for the preparation of efficient lithium metasilicate (Li 2 SiO 3) catalyst for biodiesel production via the transesterification of soybean oil and waste cooking oil. Lithium metasilicate was successfully synthesized from the hydrothermal reaction of natural diatomite in LiOH solutions at 150 °C for 24 h and, subsequently, by calcination at 500 °C for 6 h. Both fresh and spent Li 2 SiO 3 catalysts were characterized by using XRD, 29Si NMR, BET, ICP-OES and acid-base titration. The acidity of the soybean oil and waste cooking oil used in this study was 0.54 mg KOH/g oil and 1.67 mg KOH/g oil, respectively. The yields of biodiesel from soybean oil reached ca. 80.3% in 1 h, respectively, in presence of catalyst at 3 wt% of oil used. Generally, more catalyst present would lead to a higher yield of biodiesel. With the mass loading of catalyst-to-oil at 0.05, the activation energy of the catalyzed transesterification using Li 2 SiO 3 catalyst was 61.65 kJ/mol. The durability test of the Li 2 SiO 3 catalysts was conducted in the same system. A high catalytic activity after being reused for 19 times was observed with a yield of biodiesel near ca. 85% after 4 h of the transesterification reaction at 60 °C. The deactivation mechanism of the Li 2 SiO 3 catalyst was mainly attributed to the loss of surface base sites coincident with more Q4 and less Q2 Si atoms in catalyst after reaction, as found by 29Si NMR. Graphical abstract Durability of Li 2 SiO 3 catalysts in the transesterification of soybean oil with an acid value as 0.54 mg KOH/g oil. Image 1 Highlights • Lithium metasilicate (Li 2 SiO 3) hydrothermally synthesized from diatomite and LiOH. • Biodiesel produced from Li 2 SiO 3 -catalyzed transesterification of acid oil. • A yield of biodiesel >97% was achieved with Li 2 SiO 3 in 2 h-reflux reaction. • A yield of biodiesel ∼86.4% from waste cooking oil was realized with Li 2 SiO 3. • Good durability of Li 2 SiO 3 in biodiesel production was attained. [ABSTRACT FROM AUTHOR]

Preparation and characterization of bimetallic Ni–Co nanoparticle catalysts loaded on the reduced graphene oxide, denoted as Ni–Co/r-GO, for hydrogen generation from catalytic hydrolysis of sodium borohydride were studied. The reduced graphene oxide nanosheets were prepared from natural graphite. The Ni and Co metals were electrolessly deposited on the light-weighted reduced graphene oxide (r-GO) nanosheets. Process parameters affecting the hydrolysis reaction of NaBH 4 in the presence of Ni–Co/r-GO catalysts, such as NaOH and NaBH 4 concentrations, as well as catalyst loadings and reaction temperature, were investigated. A hydrogen production rate as high as ca. 1280 mL min −1 (g cat.) −1 could be obtained using the prepared Ni–Co/r-GO catalysts. The activation energy of the catalytic hydrolysis reaction of sodium borohydride was found at 55.12 kJ mol −1 from the system consisting of 10 wt% NaBH 4 and 5 wt% NaOH as well as a catalyst loading at 0.1 g catalyst per g NaBH 4 . [ABSTRACT FROM AUTHOR]

Abstract: Effects of the reduction temperature and the pH value of Pt precursor solutions of the polyol reduction process on the resulted Pt electrocatalysts supported on the reduced graphene oxide (Pt/r-GO) nanosheets for the ORR (oxygen reduction reaction) are investigated. The Pt/r-GO catalyst possesses Pt nanoparticles having an average size from 2 to 4 nm and a Pt loading from 13 to 20 wt%. The electrochemical performance of the Pt/r-GO catalysts is examined with the glassy carbon RDE (rotating disk electrode) technique in the O2-saturated HClO4 (0.5 M) solution. The Pt/r-GO catalysts have less ORR limiting currents near 3.5 mA cm−2, but, in general, the more positive onset potentials than the commercial Pt/carbon black catalysts. The number of electron transfer in ORR over the Pt/r-GO catalysts is 3.85 in average, close to that of a 4-electron transfer process. [Copyright &y& Elsevier]

Abstract: Optimization of sodium loading on zeolite HY for catalyzed transesterification of triolein in excess methanol to biodiesel was studied. Zeolite HY catalyst was activated by loading sodium ions to their surface via an ion-exchange method. The effects of ion-exchange process parameters, including the temperature, the process time, the pH value, as well as concentrations and sources of Na+ cations (NaOH, NaCl and Na2SO4), on the conversion yield of triolein to biodiesel were investigated. Most of these Na+-activated zeolite HY catalysts could really facilitate the catalyzed transesterification reaction of triolein to biodiesel at a lower temperature near 65°C. Consequently, a high conversion yield of triglycerides to biodiesel at 97.3% was obtained at 65°C. Moreover, the durability of zeolite catalysts was examined as well. Catalytic performance tests of these zeolite catalysts in transesterification did not show a significant decrease in catalysis at least for three batch cycles. [Copyright &y& Elsevier]

Abstract: Effect of limited water supply to hydrolysis of ammonia borane for hydrogen evolution is studied over the cases in which the initial molar ratio of water to ammonia borane (H2O/AB) is set at 1.28, 2.57 and 4.50. The conversion efficiency of ammonia borane to hydrogen is estimated from the accumulated volume of produced hydrogen gas and the quantitative analysis of hydrolysate by solid-state 11B NMR. Characteristics of hydrogen evolution are significantly influenced by both water dosage and injection rate of water. In the case that water is a limiting agent, namely, H2O/AB = 1.28, less hydrogen is produced than that predicted stoichiometrically. In contrast, conversion efficiency of ammonia borane reaches nearly 100% for the case with H2O/AB = 4.50. Injection rate of water to ammonia borane also affect profoundly the produced volume and production rate of hydrogen, if water is used as a limiting agent in the hydrolysis of ammonia borane. Nonetheless, boric acid and metaboric acid are found to be the dominant products in the hydrolysate from XRD, FT-IR and solid-state 11B NMR analysis. The hydrogen storage capacity using limited water supply in this work could reach as high as about 5.33 wt%, based on combined mass of reactants and catalyst. [Copyright &y& Elsevier]

Abstract: Dye-sensitized solar cells (DSSCs) were fabricated using TiO2 nanoparticles incorporating different amounts of plasma functionalized carbon nanocapsules (CNCs) as the photoanode. The functionalization was obtained by grafting maleic anhydride (MA) onto the walls of CNCs immediately after the in situ argon plasma treatment. Nanocrystalline semiconductor film electrodes were prepared by sintering TiO2 with added MA-CNCs on a conducting glass substrate. Capacitance measurements obtained from electrochemical impedance spectroscopy (EIS) analysis in an aqueous electrolyte are fitted using the Mott–Schottky relationship and demonstrate the variation of flatband potential (Vfb ) for the composite with MA-CNC content. The potential chronoamperometric and cyclic voltammetric data supports the argument that the increased Vfb minimizes the defect state for trapping/detrapping of electrons within the MA-CNC/TiO2. As a result of higher film capacitance and electron accumulation, the MA-CNC/TiO2 shows increased conversion efficiency and photocurrent density when used as the photoanode in DSSCs. EIS measurement further demonstrates that charge recombination at the interface of MA-CNC/TiO2 and electrolyte is suppressed with increasing electron lifetime and is in good agreement with the photovoltaic performance. The amount of MA-CNCs added, however needs to be optimized due to the unavoidable issue of aggregation. [Copyright &y& Elsevier]

Abstract: Hydrolysis of sodium borohydride (NaBH4) is a promising method for on-board hydrogen supply to polymer electrolyte membrane fuel cells (PEMFC). This article presents an attempt to design a novel solid-state NaBH4 composite, which is made up of NaBH4 powder, Co2+/IR-120 catalyst and silicone rubber, for hydrogen generator. The silicone rubber can act as a stabilizer in the solid-state NaBH4 composite because of its surface hydrophobicity leading to reduced diffusion rate of water into the composite. The solid-state NaBH4 composite can produce hydrogen stably near 25mLmin−1 for at least 2h without employment of any mechanical control system. Using the hydrogen generated from the solid-state NaBH4 composite, a 2W PEMFC stack is successfully operated to power a cellular phone. [Copyright &y& Elsevier]

Abstract: Solid-state composites of NaBH4 and Co-based catalyst have been fabricated for hydrogen generation via a novel mechanochemical technique, i.e. the high-energy ball milling, in which the gravimetric storage capacity of hydrogen has reached 6.7 wt%, meeting the 2010 target of at least 0.06 kg H2/kg set by the U.S. Department of Energy (DOE). The active catalysts used in the hydrolysis reaction of sodium borohydride for hydrogen generation are mainly cobalt oxides. Controlled addition of water, namely water used as a limiting agent, to the solid composites of NaBH4 and Co-based catalyst greatly improves the H2 storage capacity and resolved the issues of low gravimetric H2 storage in conventional aqueous system of sodium borohydride. Factors influencing the performance of hydrogen production such as amounts of H2O added, catalyst loadings and durations of ball-milling processes are investigated. Moreover the hydrolyzed products of NaBH4 and spent catalysts are analyzed as well. [Copyright &y& Elsevier]

Abstract: High-energy ball milling was employed to regenerate spent-sodium borohydride, i.e., mainly the sodium metaborate (NaBO2), back to sodium borohydride (NaBH4) by a reaction with magnesium hydride (MgH2). The samples were characterized using scanning electron microscopy (SEM), Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectroscopy, X-ray diffraction (XRD) and nuclear magnetic resonance (NMR) spectroscopy. In general, as the ball-milling duration increases, the yield of NaBH4 increases accordingly and leads to an extreme value of 76%, when MgH2 in stoichiometric excess by 40% was initially present in ball mills. [Copyright &y& Elsevier]

A new type of solid catalyst prepared from hydrothermal reaction of natural diatomaceous earth in NaOH solution was studied for biodiesel production through the transesterification of soybean and palm oil in excess methanol. Explicitly, the natural diatomite was transformed into efficacious catalysts, sequentially, by dispersion and activation in NaOH solutions for 30 min at 30 °C, followed by hydrothermal treatments at 180 °C or 220 °C for 12 h, and finally by calcination at 500 °C for 6 h. Coincidently, the physicochemical characteristics of these as -prepared catalysts were shown to bear a good resemblance with those of zeolite CAN. Under suitable conditions, the conversion efficiencies of soybean and palm oils to biodiesel in presence of these zeolite CAN catalysts at 63 °C and 70 °C could be obtained as high as 98.0% and 98.4%, respectively. Furthermore, the activation energies of the transesterification reactions of soybean and palm oils in excess methanol were found as 64.1 kJ/mol and 122.5 kJ/mol, respectively. [ABSTRACT FROM AUTHOR]

Paclitaxel (Taxol®) is one of the most effective anticancer drugs found from nature in recent decades, which can treat various cancers including ovarian, breast, brain, colon and lung cancer, and AIDS-related cancer. Due to its low aqueous solubility, adjuvants such as Cremophor EL, which causes serious side effects, have to be used in its administration. Our aim is to develop an alternative delivery system to achieve better therapeutic effects with minimum side effects. Paclitaxel-loaded nanospheres of biodegradable polymers were prepared by an improved solvent extraction/evaporation technique. Phospholipids, cholesterol and vitamins were used to replace traditional chemical emulsifiers to achieve high encapsulation efficiency (EE) and desired release rate of the drug. Nanospheres prepared under various conditions are characterized by the light scattering for size and size distribution, the scanning electron microscopy (SEM) and the atomic force microscopy (AFM) for surface morphology; differential scanning calorimetry (DSC) for the physical status of the drug within the polymeric matrix; the zeta-potential measurement for the surface charge properties; and X-ray photoelectron spectroscopy (XPS) for the surface chemistry. In-vitro release kinetics were measured by high-performance liquid chromatography (HPLC). Best design was pursued to develop a product for cancer chemotherapy. [Copyright &y& Elsevier]

Sol/Gel behavior of a mixture of two Pluronic species with non-identical polypropylene oxide (PPO) and polyethylene oxide (PEO) block lengths in aqueous medium is explored. Emphasis is placed on the nature of micelles (either mixed or separate micelles), nature of gelation, gel strength and microstructure. Two mixtures are considered: F127 + L64 and F127 + P105. Cooperative aggregation leading to mixed micelles is found for both cases via dynamic light scattering, differential scanning calorimetry and cloud point temperature experiments. From rheometry, F127 + L64 is found to exhibit two hard gel states separated by a soft gel as the temperature increases, although each species alone does not show such behavior. The first hard gel formed at lower temperature appears clear and has a cubic packing structure, while the second hard gel at higher temperature is hexagonally structured and appears hazy. Interestingly, the second hard gel is observed only during the temperature ramp up process, whereas the first gel is seen both in the ramp up and down processes. The aforementioned behavior does not occur for F127 + P105. [ABSTRACT FROM AUTHOR]

Abstract: Background: Folate is an essential nutrient for cell survival and embryogenesis. 10-Formyltetrahydrofolate dehydrogenase (FDH) is the most abundant folate enzyme in folate-mediated one-carbon metabolism. 10-Formyltetrahydrofolate dehydrogenase converts 10-formyltetrahydrofolate to tetrahydrofolate and CO2, the only pathway responsible for formate oxidation in methanol intoxication. 10-Formyltetrahydrofolate dehydrogenase has been considered a potential chemotherapeutic target because it was down-regulated in cancer cells. However, the normal physiological significance of 10-Formyltetrahydrofolate dehydrogenase is not completely understood, hampering the development of therapeutic drug/regimen targeting 10-Formyltetrahydrofolate dehydrogenase. Methods: 10-Formyltetrahydrofolate dehydrogenase expression in zebrafish embryos was knocked-down using morpholino oligonucleotides. The morphological and biochemical characteristics of fdh morphants were examined using specific dye staining and whole-mount in-situ hybridization. Embryonic folate contents were determined by HPLC. Results: The expression of 10-formyltetrahydrofolate dehydrogenase was consistent in whole embryos during early embryogenesis and became tissue-specific in later stages. Knocking-down fdh impeded morphogenetic movement and caused incorrect cardiac positioning, defective hematopoiesis, notochordmalformation and ultimate death of morphants. Obstructed F-actin polymerization and delayed epiboly were observed in fdh morphants. These abnormalities were reversed either by adding tetrahydrofolate or antioxidant or by co-injecting the mRNA encoding 10-formyltetrahydrofolate dehydrogenase N-terminal domain, supporting the anti-oxidative activity of 10-formyltetrahydrofolate dehydrogenase and the in vivo function of tetrahydrofolate conservation for 10-formyltetrahydrofolate dehydrogenase N-terminal domain. Conclusions: 10-Formyltetrahydrofolate dehydrogenase functioned in conserving the unstable tetrahydrofolate and contributing to the intracellular anti-oxidative capacity of embryos, which was crucial in promoting proper cell migration during embryogenesis. General significance: These newly reported tetrahydrofolate conserving and anti-oxidative activities of 10-formyltetrahydrofolate dehydrogenase shall be important for unraveling 10-formyltetrahydrofolate dehydrogenase biological significance and the drug development targeting 10-formyltetrahydrofolate dehydrogenase. [Copyright &y& Elsevier]