Natural forests exhibit higher organic carbon concentrations and recalcitrant carbon proportions in soil than plantations:a global data synthesis

Different chemical compositions of soil organic carbon(SOC)affect its persistence and whether it signifi-cantly differs between natural forests and plantations remains unclear.By synthesizing 234 observations of SOC chemical compositions,we evaluated global patterns of concentra-tion,individual chemical composition(alkyl C,O-alkyl C,aromatic C,and carbonyl C),and their distribution even-ness.Our results indicate a notably higher SOC,a markedly larger proportion of recalcitrant alkyl C,and lower easily decomposed carbonyl C proportion in natural forests.How-ever,SOC chemical compositions were appreciably more evenly distributed in plantations.Based on the assumed con-ceptual index of SOC chemical composition evenness,we deduced that,compared to natural forests,plantations may have higher possible resistance to SOC decomposition under disturbances.In tropical regions,SOC levels,recalcitrant SOC chemical composition,and their distributed evenness were significantly higher in natural forests,indicating that SOC has higher chemical stability and possible resistance to decomposition.Climate factors had minor effects on alkyl C in forests globally,while they notably affected SOC chemi-cal composition in tropical forests.This could contribute to the differences in chemical compositions and their distrib-uted evenness between plantations and natural stands.

Recent advances in the synthesis of nanoscale hierarchically porous metal–organic frameworks

Nanoscale hierarchically porous metal–organic frameworks(NHP-MOFs)have received unprecedented attention in many fields owing to their integration of the strengths of nanoscale size(<1μm)and hierarchical porous structure(micro-,meso-and/or macro-pores)of MOFs.This review focuses on recent advances in the main synthetic strategies for NHP-MOFs based on different metal ions(e.g.,Cu,Fe,Co,Zn,Al,Zr,and Cr),including the template method,composite technology,post-synthetic modification,in situ growth and the grind method.In addition,the mechanisms of synthesis,regulation techniques and the advantages and disadvantages of various methods are discussed.Finally,the challenges and prospects of the commercialisation of promising NHP-MOFs are also presented.The purpose of this review is to provide a road map for future design and development of NHP-MOFs for practical application.

Organic‐free synthesis of MOR nanoassemblies with excellent DME carbonylation performance

Seed‐assisted low alkalinity gel system was developed to explore the organic‐free synthesis of MORzeolite.MOR nanoassemblies with Si/Al ratio(SAR)up to 9.4 and high solid yield(84–94%)weresuccessfully obtained under controlled low alkalinity conditions.Characterization results demonstratethat the acid strength increases in parallel with the SAR,while the total acid amount and theproton distribution in the main channels and the side pockets are similar for the samples.The protondistribution in the H‐MOR is not straightforwardly related to the Na+distribution in theas‐synthesized MOR,implying the transfer of the protons among the oxygen sites of framework Tatom.Relative to low‐silica samples I‐5.3 and I‐7.4,sample I‐9.4 displays the best mass transferperformance and accessibility of the acid sites by pyridine due to its relatively low Al density andmild dealumination degree.Correspondingly,sample I‐9.4(pyridine‐modified catalyst)shows thebest activity with ca.100%selectivity of methyl acetate(MAc)in the DME carbonylation reaction.The high steady MAc yield(6.8 mmol/g/h)over sample I‐9.4 suggests the promising application ofMOR nanoassemblies synthesized by this economical organic‐free strategy.

Effect of different organic compounds on the preparation of CaO-based CO_(2) sorbents derived from wet mixing combustion synthesis

CaO based sorbents have great potential for commercial use to capture CO_(2) of power plants.In the demand of producing sorbents with better cyclic performance,CaO-based sorbents derived from different kinds of calcium precursors,containing calcium carbonate(CC-CaO),calcium gluconate monohydrate(CG-CaO),calcium citrate(CCi-CaO)and calcium acetate monohydrate(CA-CaO),were tested cyclically and compared using simultaneous thermal analyzer(STA).And further study was conducted on the sorbents modified with citric acid monohydrate and 50%gluconic acid solution by wet mixing combustion synthesis.The modified sorbents showed better performance and higher pore parameters as well as porous microstructure with more organic acid added.After 20 cycles of carbonation and calcination,the C2CCi8(CaO:citric acid=2:8 by mass ratio)and C2G8(CaO:gluconic acid=2:8 by mass ratio)sorbent possess CO_(2) capture capacity of 0.45g·g^(-1)(g CO_(2) per g sorbents)and 0.52 g·g^(-1) respectively.The citric acid was more effective for modification than gluconic acid for extended 50 cycles.Furthermore,good linear relationship between CaO conversion and specific surface area as well as pore volume were determined,of which the specific surface area showed closer correlation with CaO conversion。

Synthesis and Spectral Properties of Mixed-Ligand Complexes of Lanthanide Perchlorate with Bis-(phenylsulfinyl)ethane and Organic Lewis Bases

Six lanthanide complexes with bis(phenylsulfinyl)ethane(bphse) and organic bases(phen: 1,10 phenanthroline and bipy: 2,2'-bipyridine) were synthesized and characterized by elemental analysis, conductance and spectral (IR, UV Visible) data. The complexes were Ln(bphse) 2(bipy)(ClO 4) 3· n H 2O and Ln 2(bphse) 3(phen) 2(ClO 4) 6·H 2O(where Ln=Nd, Eu and Gd; n =0～2). IR spectral data confirmed that the lanthanide ions were coordinated by oxygen atoms from bphse and nitrogen atoms from phen or bipy. Exitation and emission spectra of Eu complexes were measured and discussed.

Synthesis and Crystal Structure of a Magnesium Metal-organic Framework

A magnesium metal organic framework, [N-H2（CH3）2][-N（CH3）4][Mgs（bpdc）3（O2CH）6]· 3H2O （1, bpdcH2 = 4,4＇-biphenyldicarboxylic acid）, has been solvothermally synthesized and structurally characterized. 1 crystallizes in the trigonal system, space group R-3, with a = 11.3427（3）, c = 41.5662（18） A, V = 4631.3（3） A^3, Z = 3 and the final R = 0.0457. Its structure features a pillared-layered three-dimensional network with 8.21 A cavities, in which cationic [NH2（CH3）2]^＋ or [N（CH3）4]^＋ and lattice water molecules are located. Thermal stability of the title compound has also been investigated.

Synthesis and Structural Chemistry of Two Novel Transition Metal Organic Phosphonates

Two novel transition metal phosphonate compounds, [Co（H2BDPP）（phen）]n 1 （BDPP = p-O3PCH2（C6H4）CH2PO3, phen = 1,10-phenanthroline） and [Pb3（BCP）2]n 2 （BCP = OOC（C6H4）CH2PO3）, have been synthesized and structurally determined by X-ray single-crystal diffraction. Compound 1 crystallizes in the monoclinic system, space group C2/c with a = 21.169（4）, b = 12.001（2）, c = 7.6211（15）A, β = 98.03（3）°, V= 1917.2（6）A^3, C20H18N2O6P2Co, Mr = 505.22, Z = 8, De= 1.737 g/cm^3, p = 1.107 mm^-1, F（000） = 1020, the final R= 0.0450 and wR = 0.1306 for 2072 observed reflections （I 〉 2σ（I）. Compound 2 crystallizes in the monoclinic system, space group C2/c with a = 4.7167（9）, b = 18.753（2）, c = 22.781（3）A, β = 91.07（3）°, V= 2014.7（14）A^, C8H6O5PPb1.5, Mr = 523.88, Z = 8, Dc = 3.454 g/cm^3, p = 25.222 mm^-1, F（000） = 1856, the final R = 0.0441 and wR = 0.1906 for 2259 observed reflections （I 〉 2σ（I）. In compound 1, the 1D chain running along the c axis is bridged by four ligands （trans- HO3PCH2C6H4CH2PO3H） in four different directions to extend the structure into a three- dimensional network. In compound 2, the Pb（II） displays 4- and 5-coordination modes. There is a one-dimensional P-O-Pb band along the a axis formed by PO3 groups and Pb（II） cations. These bands are joined by μ2-O of -COO to yield two-dimensional inorganic P-O-Pb layers which are pillared by the OOCC6HaCH2PO3 ligands to form a three-dimensional network. Moreover, compound 2 displays a strong emission band attributed to the ligand-centered （LC） transition.

Synthesis of Single Hexagonal-Phase AlN Nanocrystallines by a Liquid-Solid Metathetical Reaction in an Organic Solution

A liquid-solid metathetical reaction method （LSMRM） of synthesizing AIN nanocrystallines is presented. AIN nanocrystallines made through LSMRM are characterized by X-ray diffractions （XRD）, X-ray photoelectron spectroscopy （XPS）, transmission electron microscopy （TEM）, Fourier transformation infrared （FT-IR） spectroscopy, and Raman spectroscopy. The results show that the samples are single hexagonal-phase AIN and the size of the AIN samples is about tens of nanometer.

Synthesis and Performance Evaluation of Organic Bentonite Modifier Dimethyldistearylammonium Bromide (DODMAB)

Dimethyldistearylammonium Bromide (DODMAB) is a bentonite modifier with good performance. In this experiment, 1-Bromooctadecane is the raw material, and completes tertiary amination and quaternization successively by changing the condition of experiment. The result is that the productivity can achieve 78.94% in the synthesis of DODMAB. It has been used in the experiment of bentonite modification and achieves good results;compared with using trimethylstearylammonium bromide as the organic modifier, the synthetic organic bentonite has better performance than the common organic modifier when used in the oil base drilling fluid of oilfield operation.

Asymmetric Synthesis of (-)-1-Trimethylsilyl-ethanol with Immobilized Saccharomyces Cerevisiae Cells in Water/Organic Solvent Diphasic System

Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied. The effects of shake speed, hydrophobicity of organic solvent, volume ratio of water phase to organic phase, pH value of aqueous phase and reaction temperature on the initial reaction rate, maximum yield and enantiomeric excess (ee) of the product were systematically explored. All the above-mentioned factors had significant influence on the reaction. n-Hexane was found to be the best organic solvent for the reaction. The optimum shake speed, volume ratio of water phase to organic phase, pH value and reaction temperature were 150 r.min-1, 1/2, 8 and 30 ℃ respectively, under which the maximum yield and enantiomeric excess of the product were as high as 96.8% and 95.7%, which are 15% and 16% higher than those of the corresponding reaction performed in aqueous phase. To our best knowledge, this is the most satisfactory result obtained.

REDUCTION BY HYPOPHOSPHOROUS ACID IN ORGANIC SYNTHESIS

Hypophosphorous acid and its salt were found to serve as a new agent for selective reduction of α,β-unsaturated carbonyl compounds under mild reaction conditions.

Hydrothermal Synthesis,Structure and Properties of a 3D Pillar-layered Metal-organic Framework Based on Amino-arenedisulfonate Ligand

One novel metal-organic framework(MOF), [Ba(L)(HO)](1, HL =aniline-2,5-disulfonic acid), has been synthesized by hydrothermal method. Each barium atom is eleven-coordinated into a distorted monocapped pentagonal antiprismatic arrangement. Compound 1 shows an interesting 3 D pillar-layered structure constructed from 2 D inorganic layers[Ba(SO)(HO)]and organic pillars of phenyl moieties of L2-linkages. The inorganic layers are supported by the organic pillars, generating a novel 3 D open framework structure with {3, 4~6, 5~5, 6~5,7~4}2{3}{5} topology. The result of fluorescence measurement can reveal that the decayed emission band centered at 492 nm may be caused by the interactions of the ligands and the metal ions.Compound 1 exhibits selective toward the adsorption of COover Nat 273 K.

APPLICATION OF THE SULFONATE ESTER GROUP AS A LINKER FOR SOLID PHASE ORGANIC SYNTHESIS

A use of Sulfonate ester as a linker in synthesis of (-aminoalkanols was reported. Diols were tethered onto polystyryl sulfonyl chloride resin, yielding sulfonate resins (2). After cleaved by diethyl amine, diisopropylamine and propylamine respectively, three (-aminoalkanols were obtained.

A Novel Organic-Inorganic Complex: Synthesis and Crystal Structure of [Ca(DMSO)_5(H_2O)]_2SiMo_(12)O_(40)

A novel organic-inorganic complex [Ca(DMSO)5(H2O)]2SiMo12O40 was synthesized from CaCl2, DMSO and H4SiMo12O40nH2O in mixed solvent of acetonitrile and water. Its structure was characterized with elemental analysis, IR and X-ray diffraction analysis.

Chemoenzymatic Synthesis of Cellular Adhesion Tripeptide RGD Precursor in Organic Media

Chemoenzymatic synthesis of tripeptide Bz-RGD-（OEt）2 was conducted in this study. First, the free dipeptide Gly-Asp was synthesized via a novel chemical method, wherein only L-aspaxtic acid was used and was followed by the esterification of Gly-Asp. The formation of the linkage between the third amino acid Bz-Arg-OEt and Gly-Asp-（OEt）2 was completed by using the enzymatic method in organic media. The effects of several factors such as pH, the water content, triethylamine （TEA）, the molar ratio of the substrates, and the reaction time on the yield of Bz-RGD- （OEt）2 were examined. It was obtained that the optimum conditions for Bz-RGD-（OEt）2 synthesis in an ethanol/ Tris-HC1 buffer system （ volume ratio 93： 7 ） were as follows ： pH = 8.0 ; temperature, 30 ℃ ; reaction time, 7 h. The tripeptide yield was 75.2%.

Synthesis and Characteristics of Organic Bentonite Gel

The bentonite was modified using Ca-bentonite as a matrix and octadecyl/ hexndecyl ammonium chloride as the cover agent, based on hydrothermal process. The organic gel with 5.0 Pa· s viscosity was synthesized by dispersing it into the dimethyl benzene- methyl alcohol system fully. The optimum process conditions for organic modification were that the coating agent dosage is 22g/ L, reaction time is 90 minutes and the pH value of pulp is 10. X-ray diffraction （ XRD ） analysis indicates that the d （001） value of the modified bentonite is 20. 532 A. The influence of gel temperature on its viscosity characteristic was studied. By analyzing the transmssion electron microscopy （TEM） images and observing the dispersed gel, the nanometer effect of the organic gel was discussed.

Application of CO_2-TPD in the Synthesis of Composite Oxides from Metal-Organic Precursors

CO2-TPD was demonstrated an effective way to investigate the phase formation during pyrolysis for the preparation of composite oxides using metal-organic molecules as precursors.Based on the CO2-TPD results, it was found that calcination condition had deep effect on the carbonate formation and the minimum firing temperature to acquire pure phase composite oxide.An optimized calcination schedule was then developed.

Synthesis of Pyrazolines Used as Blue Organic Electroluminescence Materials

Three kinds of pyrazolines were designed and synthesized. Their structures were elucidated by IR, (HNMR)-H-1, MS, UV and elemental analysis. Their luminescent properties were determined, which indicated that they had strong blue fluorescent properties. One of them was designed to have good film formation. All the three kinds of pyrazolines can be used as blue organic electroluminescence materials (OELMs).

Hydrothermal Synthesis and Characterization of a Novel Organically-templated Tungsten Heteropolyacid with a Microporous Structure

A microporous organically-templated tungsten heteropolyacid, (C2N2H10)2 [H2P2W18O62]?8H2O, with a new type was hydrothermally synthesized by using ethylenediamine as the structure-directing agent. Its structure was determined by single-crystal X-ray diffraction analysis. Crystal data: monoclinic, space group P21/c, a = 14.633(4), b = 19.432(5), c = 26.776(5) ?, β = 117.849(11)o, V = 6732(3) ?3, Z = 4, Mr = 4615.48, Dc = 4.554 g/cm3, μ(MoKα) = 30.781 mm-1, F(000) = 7976, the final R = 0.0678 and wR = 0.1359. The crystal of the title compound is constructed by Dawson anions and organic dications forming a novel “hollow” channel system.