Redefining biofuels:Investigating oil palm biomass as a promising cellulose feedstock for nitrocellulose-based propellant production

This review paper explores the potential of oil palm biomass as a valuable cellulose source for the production of nitrocellulose-based propellants,contributing to the green revolution and sustainable energy solutions.It highlights the availability of the corresponding biomass in Malaysia and in line with global studies,the chemical compositions,as well as a brief description of current technologies for converting biomass of oil palm into value added products specifically cellulose.Steps to achieve maximum utilization of biomass from oil palm industry for cellulose production and prospective source for nitrocellulose-based propellant are also proposed.The methodology section outlines the pretreatment of lignocellulosic fibres,cellulose extraction,and nitrocellulose production processes.Overall,the review underscores the prospective of palm oil biomass as a sustainable cellulose source for propellant manufacturing,while acknowledging the need for further research and advancements in the field.

Annual Time-series Analyses of Total Gaseous Mercury Measurement and its Impact Factors on the Gongga Mountains in the Southeastern Fringe of the Qinghai-Tibetan Plateau

Long-term monitoring programs for measurement of atmospheric mercury concentrations are presently recognized as powerful tools for local,regional and global studies of atmospheric long-range transport processes,and they could also provide valuable information about the impact of emission controls on the global budget of atmospheric mercury,their observance and an insight into the global mercury cycle. China is believed to be an increasing atmospheric mercury emission source. However,only a few measurements of mercury,to our knowledge,have been done in ambient air over China. The highly-time resolved atmospheric mercury concen-trations have been measured at Moxi Base Station (102°72′E 29°92′N,1640 m asl) of the Gongga Alpine Ecosystem Observation and Experiment Station of Chinese Academy of Sciences (CAS) from May 2005 to June 2006 by using a set of Automatic Atmospheric Mercury Speciation Analyzers (Tekran 2537A). Measurements were carried out with a time resolution of every 15 minutes. The overall average total gaseous mercury (TGM) covering the measurement periods was 4±1.38 ng·m-3 (N=57310),which is higher than the global background level of approximately 1.5～2.0 ng·m-3. The measurements in all seasons showed a similar diurnal change pattern with a high concentration during daytime relative to nighttime and maximum concentration near solar noon and minimum concentration immediately before sunrise. The presence of diurnal TGM peaks during spring and summer was found earlier than that during autumn and winter. When divided seasonally,it was found that the concentrations of TGM were highest in winter with 6.13 ± 1.78 ng·m-3 and lowest in summer with 3.17 ± 0.67 ng·m-3. There were no significant differences in TGM among wind sectors during each season. Whereas Hg generally exhibited significant correlations with the parameters,such as temperature,saturated vapor pressure,precipitation,ultraviolet radiation (UV) and atmospheric pressure at the whole measurement stage,and the correlations varied seasonally. Our results suggest that the local or regional abundant geothermal activities,such as thermal spring,anthropogenic source processes and changes in meteorological conditions,regulate and affect Hg behavior in the study area.

Zinc Borohydride-Ionic Liquid: Stable and Efficient System for Reductive Reaction of Aldehydes with Primary Amines to Corresponding Secondary Amines

Ionic liquids（ILs） are attracting much attention in various fields of chemical synthesis, electrochemical applications, liquid-liquid extractions, as well as biotransformations. Among those fields, the application of ILs as the potential green solvent for a wide variety of synthetic processes is an area of intense researches. High yield, high selectivity, and good catalytic charac-teristics have usually been achieved. After the isolation of products, ILs can usually be recovered and recycled many times by simple treating procedures, such as, filtration, extraction, and dryness.

COVID-19 and the gastrointestinal tract:Source of infection or merely a target of the inflammatory process following SARS-CoV-2 infection?

Gastrointestinal(GI)symptoms have been described in a conspicuous percentage of coronavirus disease 2019(COVID-19)patients.This clinical evidence is supported by the detection of viral RNA in stool,which also supports the hypothesis of a possible fecal-oral transmission route.The involvement of GI tract in severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection is corroborated by the theoretical assumption that angiotensin converting enzyme 2,which is a SARS-CoV-2 target receptor,is present along the GI tract.Studies have pointed out that gut dysbiosis may occur in COVID-19 patients,with a possible correlation with disease severity and with complications such as multisystem inflammatory syndrome in children.However,the question to be addressed is whether dysbiosis is a consequence or a contributing cause of SARS-CoV-2 infection.In such a scenario,pharmacological therapies aimed at decreasing GI permeability may be beneficial for COVID-19 patients.Considering the possibility of a fecal-oral transmission route,water and environmental sanitation play a crucial role for COVID-19 containment,especially in developing countries.

Synthesis of Ni@Au Core-shell Nanoparticles and Its Applications in Ullmann Reaction as a Synergistic Catalyst

The Ni@Au core-shell nanoparticles had been successfully synthesized from aqueous solution by one-step route at room temperature. The Ni@Au nanoparticles can be an excellent catalyst for Ullmann reaction. The advantage of Ni@Au is that the catalyst does not need additional reducing agents. The Au shell can effectively protect the Ni core from oxidation. The Ni core and Au shell have both composited in structure and cooperated in function.

Crystal Structure,Thermal Behavior and Luminescence of a One-dimensional Coordination Polymer [Zn(4-CPOA)(Phen)(H_2O)]_n

A novel coordination polymer of [Zn（4-CPOA）（Phen）（H2O）]n （C21H16N2O6Zn,1,4-CPOA = 4-carboxylato-phenoxyacetate dianion and Phen = 1,10-phenanthroline） has been synthesized and characterized by elemental analysis,IR,TG,PL and single-crystal X-ray diffraction. The crystal crystallizes in the triclinic system,space group of P1 with a = 9.622（3）,b = 9.631（3）,c = 11.526（4）A,α = 67.719（5）,β = 71.203（5）,γ = 83.552（6）o,V = 935.5（5） A^3,Z = 2,Dc = 1.625 g/cm^3,μ = 1.357 mm^-1 and F（000） = 468. The Zn（II） ion is surrounded by three carboxylate O atoms from two different 4-CPOA groups,two N atoms from the Phen ligand and one water molecule,forming a distorted octahedral coordination configuration. The Zn（II） ions were alternately interlinked by carboxylate groups of 4-CPOA with chelating bisbidentate and monodentate modes into a one-dimensional zigzag chain having an intrachain distance of ca. 9.631（1） . Under the direction of supramolecular recognition and attraction,the adjacent chains yield a double-stranded chain through π-π stacking between the phen ligands,which was further expanded into a 2-D framework via strong C–H–π interaction （ca. 2.95（1） ） between the 4-CPOA ligands and into a 3-D supramolecular network by strong hydrogen bond between terminal water molecule and carboxyl group. TG/DTG shows that its chain skeleton is thermally stable up to 419 oC and the blue fluorescent emission of the complex was determined at 471 nm in a solid state with its long decay lifetime of 1.83 ns.

γ-Fe_2O_3:A magnetic separable catalyst for synthesis of 5-substituted 1H-tetrazoles from nitriles and sodium azide

An efficient route for the synthesis of 5-substituted 1H-tetrazole via[2＋3]cycloaddition of nitriles and sodium azide is reported usingγ-Fe2O3 nanoparticles as a magnetic separable catalyst.Under optimized conditions,the moderate to good yields（71-95%） can be obtained.The catalyst can be easily separated by a magnet and reused for several circles.

Evaluation of Dissolved Organic Carbon Using Synchronized Fluorescence Emission Spectra and Unsupervised Method of Principal Component Analysis (PCA) and Independent Component Analysis (ICA)

Dissolved organic matter (DOM) can be originated from autochthonous or allochthonous sources, where allochthonous DOM can be from pedogenic sources (humic substances—HSs) or anthropogenicsources (wastewater). The analysis of fluorescence emission, excitation, synchronous or excitation-emission matrix (EEM) have been used to identify the main source or probable contribution of dissolved compounds, such as humic acids (HA), fulvic acids (FA) and dissolved organic carbon (DOC) from sewage, but does not quantify. Fluorescence emission is a powerful technique to detect and qualify organic dissolved compounds but fails in quantitative aspects. In this work, we propose an in situ method for direct determination of DOC using synchronous fluorescence spectra with independent component analysis (ICA). Well known standard solutions were used for method development and validation. In this work, we show that it is possible to predict the number of independent contributions using an unsupervised method based on iterative Principal Component Analysis and Independent Component Analysis (PCA-ICA) approach over combined matrix results. Within these results it’s also possible to see that with a very small amount of independent components it is possible to describe environmental samples of HA, FA and primary productivity (PP).

Safflower (Carthamus Tinctorius L.) a Potential Source of Drugs against Cryptococcal Infections, Malaria and Leishmaniasis

In this research we present that Carthamus Tinctorius L.(gen.Asteraceae,otherwise known as Safflower)(Fig.1)may contain agents active in Cryptococcal infections,malaria and Leishmaniasis,as treatment options are becoming scarce due to drug resistance development.Phytochemistry and pharmacological activities(antimicrobial,antimalarial,antileishmanial)of C.tinctorius L.were analyzed.The composition of volatile oil of safflower dried flowers was analyzed by gas chromatography-mass spectrophotometry with flame ionization detector(GC-FID)and in vitro sensitivity assays were performed to assess biological activity.8 known and 3 unknown compounds were detected in the extract(Fig.1).Then the Safflower ointment was manufactured and its acute toxicity study on rats was tested.The volatile oil of C.tinctorius L exhibited activity against Cryptococcus neoformans,Plasmodium falciparum and Leishmania donovani.Safflower volatile oil has anticryptococcal,antimalarial and antileishmanial effects.The prepared ointment had an excellent acute toxicity safety profile.

Dispersing and Doping of BaTiO_3 Powder by Adsorption

Dispersing and doping of BaTiO3 powder by adsorption method were investigated. Ultrafine BaTiO3 powders were dispersed in the aqueous with ammoniumized citrate （NHa-CA） or ammoniumized citric lanthanum chelate （NH4-La-CA） as dispersant by ultrasonic bath. Better dispersion of BaTiO3 slurry was obtained in the aqueous with NH4-La-CA than that of NH4-CA when the mass ratio of citric acid （CA） to BaTiO3 was less than 0,007. The pH value hardly affects the dispersion property of BaTiO3 suspension dispersed by NH4-La-CA. BaTiO3 powder could be well dispersed （median size D50=0.45 μm） and also doped with high uniformity of added components by adsorbing citric acid chelate on surface. Compared with solid mixing, better microstructure and properties of La/Mn codoped ceramics were obtained by adsorption method.

Crystal Structures of Schiff Base from 4-Aminoantipyrine and Pyridine-2-carboxaldehyde and Its Perchlorate

The Schiff base pyridine-2-carboxaldehyde-4-aminoantipyrine （CI7H16N4O 1） and its perchlorate （C17H17N4O·ClO4 2） have been prepared and characterized by elemental analysis, IR spectra and single-crystal X-ray crystallography analysis. Both 1 and 2 crystallize in the monoclinic system, space group P21/c. For 1, a = 8.6820（12）, b = 24.934（3）, c = 7.0064（10） A,, β= 97.942（3）°, V = 1502.2（4） A^3, Z = 4, Dc = 1.293 g/cm^3, F（000） = 616,μ = 0.084 mm^-1, the final R = 0.0592 and wR = 0.1244. For 2, a = 5.9302（2）, b = 20.347（7）, c = 14.663（6） A, β= 90.200（9）°, V= 1769.201） A^3, Z = 4, Dc = 1.475 g/cm^3, F（000） = 816, μ = 0.254 mm^-1, the final R = 0.0533 and wR = 0.0819. As expected, both molecular structures of 1 and 2 adopt a trans configuration about the central C=N double bond. 2 is an ionic compound with the protonation at N（1） of pyridine-2-carboxaldehyde-4- aminoantipyrine.

Synthesis,Crystal Structure and Luminescent Properties of a Mn(Ⅱ) Complex Constructed from 2,2'-Bibenzimidazole

A new complex associated with Mn ion,[Mn（Hbibm）（SO4）]·0.5H2O（1,Hbibm= 2,2＇-bibenzimidazole）,was prepared under solvothermal conditions,and characterized by single-crystal X-ray diffraction,elemental analysis and IR spectra.The complex belongs to the triclinic system,space group P1 with a=8.9250（5）,b=12.8022（8）,c=13.3505（8）,α=66.614（2）,β= 72.567（2）,γ=80.627（2）°,V=1334.1（1）3,Z=1,Dc=1.565 g/cm3,S=0.996,μ=0.628 mm-1,F（000）=644,R=0.0447 and wR=0.0586 for 5155 observed reflections（Ⅰ〉 2σ（Ⅰ））.Complex 1 is a mononuclear Mn（II） complex.The π-π interactions and interchain hydrogen-bonding interactions further extend the mononuclear for 1,generating a 3D supramolecular architecture.Complex 1 shows strong blue fluorescent emissions in the solid state upon 395 nm photo-excitation at room temperature.

Syntheses and Crystal Structures of Ternary Complexes of Zinc(Ⅱ) and Cadmium(Ⅱ) with 3-Aminobenzoic Acid and 1,10-Phenanthroline

Two new ternary complexes [Zη（3-aba）2（phen）]·2.58H2O 1 and {[Cd（3-aba）- （phen）2]·（NO3）·（1.5H2O） }n 2 （3-aba = 3-aminobenzoic acid anion, phen = 1,10-phenanthroline） were synthesized and characterized by elemental analysis, IR, UV spectrum and X-ray diffraction. Complex 1 crystallizes in the rhombohedral system, space group R3 with a = 3.5733（3）, b = 3.5733（3）, c = 1.1231（2） nm; V= 12.419（3） nm^3, C26H25.17NaO6.58Zn, Mr= 564.37, Z= 18, F（000） = 5253, μ= 0.937 mm^-1, Dc = 1.358 g/cm^3, R = 0.0668 and wR = 0.1690 for 2424 observed reflections （I〉 2σ（I））. Complex 2 belongs to the tetragonal system, space group P4/ncc with a = 2.88451（10）, b = 2.88451（10）, c = 1.55571（11） nm, V= 12.9441（11） nm^3, C31H25CdN6O6.50, Mr = 697.97, Z = 16, F（000） = 5648,μ=0.727 mm^-1, Dc= 1.433 g/cm^3, R = 0.0607 and wR = 0.1742 for 3468 observed reflections （I 〉 2σ（I））. Complex 1 displays a mononuclear structure. The carboxylate group of 3-aminobenzoic acid anion coordinates to Zn（Ⅱ） in a chelating bidentate mode, and the nitrogen atom of the ligand does not involve in coordination. Complex 2 exhibits a one-dimensional chain structure with 3-aminobenzoic acid anion coordinating to Cd（Ⅱ） in a μ2-bridging mode through its nitrogen atom and one of its oxygen atoms.

Synthesis and Crystal Structure of a Novel Tetranuclear Zinc(Ⅱ) Coordination Polymer [Zn_4(o-bda)_4(p-pbim)_4]_n

A novel tetranuclear zinc（H） coordination polymer [Zn4（o-bda）a（p-pbim）4]n 1 （p-pbim = 4-pyridylbenzimidazole, o-bda2 = o-phenylenediacetic acid dianion） has been synthesized by a hydrothermal method and characterized by elemental analysis, IR and X-ray singlecrystal diffraction. The title complex crystallizes in monoclinic, space group of P21/n with α = 14.231（1）, b = 16.257（1）, c = 16.794（1） ]k, β = 100.26（1）°, V = 3823.1（2）A3, Z = 8, Dc = 1.573 g/cm^3,β = 1.321 mm^-1, F（000） = 1856, R = 0.0420 and wR = 0.111. The Zn（1） atom assumes a distorted trigonal bipyramidal geometry, involving three carboxyl O atoms from two different o-bda ligands and two N atoms from two p-pbim ligands. The Zn（2） atom is coordinated by two oxygens from two distinct bda2- anions and two nitrogen atoms from two p-pbim ligands to form a distorted tetrahedral geometry. The Zn（Ⅱ） atoms are alternately interlinked by o-bda ligands in bis-monodentate or chelating-bidentate and monodentate modes into one-dimensional undulate chains along axis c with the adjacent Zn…Zn distances of 8.32 and 8.47 A. Such neighboring chains are further extended into a 1D bi-chain structure with two different subrings A and B, which are 32- and 14-membered rings through interchain p-pbim ligands. There exists a 2D supramolecular network linked by intermolecular hydrogen-bonding interactions between the uncoordinated carboxylate 0（4） atom or coordinated carboxylate 0（7） atom and the uncoordinated imidazolyl N（2） and N（5） atoms with the O...N distances to be 2.695 and 2.807A.

Synthesis,Crystal Structure and Spectrum Characterization of Schiff Base Isonicotinaldehyde Thiosemicarbazone

The Schiff base isonicotinaldehyde thiosemicarbazone prepared by the condensation of thiosemicarbazide with pyridine-4-carbaldehyde in ethanol,has been characterized by IR,UV-Vis,element analysis and its stucture determined by singl-crystal X-ray diffraction techniques from diffractometer data,Crystal of C7H8N4S is Monoclinic,space group P21/n,with unit cell parameters:a=7.241(1),b=13.963(2),c= 8.416(1),β=90.92°,V=850.91(44)3,Dc=1.407Mg/m3,Z=4,Mr=180.23,μ= 0.327mm-1,F(000)=376,final R1= 0.0315 and wR2= 0.0821(I>2 σ(I)).The crystal packing is stabilized by an extensive two dimensional double layer network of hydrogen bonds(N-H...N and N-H...S).

Degradation properties of fulvic acid and its microbially driven mechanism from a partial nitritation bioreactor through multi-spectral and bioinformatic analysis

This study employed multispectral techniques to evaluate fulvic acid(FA)compositional characteristic and elucidate its biodegradation mechanisms during partial nitritation(PN)process.Results showed that FA removal efficiency(FRE)decreased from 90.22 to 23.11%when FA concentrations in the reactor were increased from 0 to 162.30 mg/L,and that molecular size,degree of aromatization and humification of the effluent FA macromolecules all increased after treatment.Microbial population analysis indicated that the proliferation of the Comamonas,OLB12 and Thauera exhibit high FA utilization capacity in lower concentrations(<50.59 mg/L),promoting the degradation and removal of macromolecular FA.In addition,the sustained increase in external FA may decrease the abundance of above functional microorganisms,resulting in a rapid drop in FRE.Furthermore,from the genetic perspective,the elevated FA levels restricted carbohydrate(ko00620,ko00010 and ko00020)and nitrogen(HAO,AMO,NIR and NOR)metabolism-related pathways,thereby impeding FA removal and total nitrogen loss associated with N_(2)O emissions.

Targeting AMPKa1 Gene in PC3 Cells by Triphenylmethanol Derivatives

Epidemiological studies indicate that treatment with metformin, an AMP-activated protein kinase (AMPK) activator, reduces the incidence of cancers. Activation of AMPK has also been reported to oppose tumor progression in diverse types of cancers and offers promising cancer therapy. Furthermore, AMPK is a primary regulator of energy metabolism and has also been implicated in cell cycle progression, angiogenesis, cell transformation, migration, and cancer. We have recently synthesized novel flavonoids, namely, triphenylmethanol derivatives (TPMs), but the effectiveness of the TPMs on the activity of AMPK remains unclear. We hypothesized that the novel TPMs would inhibit cancer cell proliferation through the activation of AMPK isoforms in cells. The effects of TPMs on prostate cells (PC-3) were investigated. Cells were exposed to TPMs for either 12 or 24 hr. at the respective doses of 0, 25, 50 100, and 200 µM based on the cell viability studies by the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a tetrazole) (MTT) assay. The results indicate that cells exposed to the respective doses of TPMs increased both phospho- and total-AMPKα1 in a dose- and time-dependent manner. The effects of the increases for the phospho- and total-AMPKα in cells were greater for the 24-hr than the 12-hr. incubation. Further studies are currently going on to elucidate the specificities of the said insults in increasing the phospho- and total-AMPKα activities and for the other respective isoforms.

Single nucleotide polymorphism C677T in the methylenetetrahydrofolate reductase gene might be a genetic risk factor for infertility for Chinese men with azoospermia or severe oligozoospermia

Aim： To analyze the distribution of the single nucleotide polymorphism （SNP） C677T in the methylenetetrahydrofolate reductase （MTHFR） gene in 355 infertile Chinese patients with idiopathic azoospermia or severe oligozoospermia and 252 fertile Chinese men as controls to explore the possible association of the SNP and male infertility. Methods： Using the polymerase chain reaction （PCR）-restriction fragment length polymorphism technique, the allele and genotype distribution of SNP C677T in the MTHFR gene were investigated in both patients and controls. Results： The frequencies of allele T （40.9% vs 30.4%, P = 0.002, odds ration [OR] = 1.58, 95% confidence interval [CI]： 1.24-2.02） and mutant homozygote （TT） （18.3% vs. 11.5%, P = 0.023, OR = 1.72, 95% CI： 1.07-2.76） as well as carrier with allele （TT ＋ CT） （63.4% vs. 49.2%, P = 0.0005, OR = 1.79, 95% CI： 1.29-2.48） in infertile patients were significantly higher than those in controls. After patient stratification, the significant differences in distribution of the SNP between each patient subgroup and control group still remained. Conclusion： Our findings indicate that there is an association of SNP C677T in the MTHFR gene with male infertility, suggesting that this polymorphism might be a genetic risk factor for male infertility in Chinese men.