THE PHOTOCHEMICAL SYNTHESIS OF THE PYRIDINE ADDUCT OF TETRAPHENYLPORPHYRINATORHODIUM(Ⅱ)AND THE MECHANISM OF PHOTOCHEMICAL REACTION

A new rhodium(Ⅱ)porphyrin complex was isolated by chromatography from the photochemical reac-tion of(μ—tetraphenylporphyrinato)bis[dicarbonylrhodium(Ⅰ)]with pyridine in benzene and has been charac-terized.From the results,the reaction mechanism is proposed.     

THE SPECTRA OF BAROTROPIC QUASIGEOSTROPHIC MODEL AND THE EVOLUTION OF DISTURBANCES

The spectra of linearized barotropic quasigeostrophic model is one of classical but not yet completelysolved problems in dynamic meteorology. This paper is devoted to a detailed investigation of this problem.It is obtained that in the case of zonal basic flow μ(y), there exist two types of spectra, the discrete andcontinuous. Each discrete spectrum (eigenvalue) gives an eigenfunction (normal mode); and the real num-bers in the interval [μ_(min), μ_(max)] are the continuous spectra; every point c ? [μ_(min), μ_(max)] gives a spectralfunction which is bounded and whose derivative is unbounded but integrable. Every disturbance can berepresented as a linear combination of two parts, ψ'(x, y, t) and ψ'(x, y, t), the former is expressed bythe discrete spectra, and the latter by the continuum. ψ'_d can be easily derived from the initial conditionby the use of the generalized "weighted orthogonality" of normal modes. It is also proved that ψ'_c as wellas its energy E'_c and mean y-direction scale l_c a     

STUDIES ON THE SYNTHESIS OF THE SPIROKETAL FRAGMENT OF AZADIRACHTIN(Ⅰ)

The stereoselective synthesis of substituted [2,2,1]-bicyclo-heptan-2-one 12,a supposed intermediate to the spiroketal fragment of azadi-rachtin was described.When 12 was treated with mCPBA in CH_2Cl_2 in the pres-ence of excess amount of solid sodium bicarbonate,only 13 was obtained.Thespiroketal intermediate 20 was converted from 9 through 5 steps by an alterna-tive route.     

ADSORBENTS USED IN THE CLEARANCE OF ENDOTOXIN

1.INTRODUCTION[()-227.3()]Endotoxinislipopolysaccharide(LPS)derivedfromthecellmembranesofgram-negativebacteria.Endotoxincancausefebrilereactionsinanimalswithsymptomsofhighfever,vasodilation,diarrheaandfetalshockwheninjectedeveninaverysmallamount[1].Iftheconcentrationofendotoxininpatients?bloodishighenoughitcancauseseveresepsis,whichisamajorcauseofdeathinpatientsandcontinuestohaveahighmortalitydespiteappropriatesurgery,potentantibiotic,andintensivesupportivetherapy[2~5].LipidAisthemaintox…     

THE MECHANISM OF THE COPOLYMERIZATION OF BF_3-COMPLEXED ETHYL ACRYLATE WITH PROPYLENE

The copolymerization of BF_2-omplexed ethyl acrylate with propylene in the presence ofAIBN at 25℃was investigated. It was found that the rate of the copolymerization was propor-tional to the square root of the initiator concentration. The chain transfer agent CCl_4 greatly af-fects the inherent viscosity of the resulting copolymer. The smaller the dielectric constant of thesolvent, the greater the rate of copolymerization is. The equal concentration of the two monomersgive the maximum copolymerization rate. The ~1H-NMR and ~(13)C-NMR analysis indicated, when[EA.BF_2]/[EA.BF_2]+[P]>0.5, the resulting copolymer was the acrylate-rich random copoly-mer. Through the kinetic experiments we suggest that copolymerization follows the mechanismof the random copolymerization of the ternary complex with binary complex. When [EA.BF_3]/[EA.BF_2]+[P]<0.5, the resulting copolymer is always strictly alternating, and the alternatingcopolymerization follows the mechanism of the ternary complex homopolymerization. Usingthe homolog of the propylene, 1-pentene, we found that BF_3-complexed ethyl acrylate can forma ternary complex with 1-pentene identified by UV spectroscopy. This is a strong evidence forthe mechanism of ternary complex homopolymerizetion.     

DETERMINATION AND REFINEMENT OF THE CRYSTAL STRUCTURE OF CHAIDAMUITE

Chaidamuite (ZnFe(SO_4)_2(OH). 4H_2O), which is a new sulphate mineral, belongs to the triclinic system, space group P1, with the cell parameters corrected by the least-squares method: a=7.309(2), b=7.202(2), c=9.691(3), α=89.64(3), β=105.89(3), γ=91.11(2)°, Z=2. The crystal structure has been determined by the Patterson method and Fourier syntheses and refined by the full-matrix least-squares method to an R factor of 0.032, using 2833 independent reflections. In the structure, a zigzag chain consists of [Fe(1)O_5(OH)] and [Fe(2)O_5(OH)] octahedra sharing the OH corners, and an octahedral-tetrahedral chain running parallel to the b axis consists of the zigzag chain of Fe octahedra and (SO_4) tetrahedra sharing four pairs of octahedral corners on either side of the zigzag chains. These chains are cross-linked by the isolated [Zn(1)O_2(H_2O)_4] and [Zn(2)O_2(H_2O)_4] octahedra into corrugated sheets parallel to the (100) plane. Adjacent sheets are hydrogenbonded through water molecules.     

A STUDY OF THE GLUCOCORTICOID RECEPTOR OF THE CYTOSOL AND NUCLEI IN NONLETHALLY AND LETHALLY SCALDED RATS

The glucocorticoid receptor (GCR) of the cytosol of liver and brain was studied by radioligand binding assay, using [~3H] dexamethasone (Dex) as the ligand in lethally and nonlethally scalded rats. As compared with controls, the binding capacity (R_0) was decreased and the apparent K_d of [~3H] Dex specific binding was increased in both scalded groups. In the lethal group, the R_u is much lower than that in the nonlethal group. In order to determine whether the decrease of R_0 was due to the translocation of [~3H] Dex-GCR complex into the cell nuclei, the [~3H] corticosterone (B) specific binding of the hepatic nuclei was measured by the exchange assay. There was no significant difference between the control and scalded groups. The possible mechanisms and the clinical significance of these changes were discussed.     

THE DEVELOPMENT OF THE THEORY OF MOLECULAR STRUCTURE AND THE NATURE OF THE CHEMICAL BOND

THE development of the theory of molecular structure and thenature of the chemical bond are discussed.Particular atten-tion is given to the theory of hybrid bond orbitals.     

STUDY ON THE EFFECT OF POLYSTYRENE SULFONIC ACID MACROMOLECULES ON THE POLYMERIZATION OF ACRYLAMIDE

The effect of polystyrene sulfonic acid (PSSA) macromolecules on the polymerization of acrylamide (AM) has been studied. It was found that the rates of polymerization of AM were greatly increased in the presence of PSSA in the polymerization system.The maximum value of the rate of polymerization of AM was obtained when the ratio of [—SO_3H]: [AM] reached 3:1. When the insoluble crosslinked PSSA was used instead of the soluble one, this effect decreased considerably. The interaction between molecules of PSSA and AM was determined by infrared spectroscopy, elementary analysis and X-ray photoelectron spectroscopy. The combination form, —SO_3-NH_3~ CO—, formed between sulfonic group and amide group was found to be existed since the infrared absorption band of —NH_2 shifted from 3400cm~(-1) to 3150 cm~(-1), the binding energy of electron N_(18) changed from 399.7 eV to 401.3 eV, and the atomic ratio of N to S of the products was similar to the ratio of reagents. Based on these experimental results, the mechanism of AM polymerization in the presence of PSSA is proposed. The initial step is the combination of AM with sulfonic group to form —CONH_3~ , then followed by polymerization on the PSSA macromolecule. The role of PSSA on the polymerization of AM is discussed.     

THE STUDY OF INTERACTION OF SOLID-LIQUID ADSORPTION SYSTEM BY USING THE FLOW INJECTION-SPECTROPHOTOMETRY SYSTEM

1. INTRODUCTION Flow injection analysis is a method that a determinate volume of sample is injected to an airless and continuous flow carrier consisted of suitable liquids, and then is put into a detector to be record absorbency, electrode potential and other physical parameters. This automatic analytical method is characterized by fixed time, quantified sampling, less sampling and good system stability [1]. The new automatic analysis for liquid has been developed quickly since Ruzi…     

EXAMINATION OF THE SURFACE FREE ENERGY AND ACID-BASE PROPERTIES OF CELLULOSE BY THE COLUMN WICKING TECHNIQUE AND THE CRITICAL PACKING HEIGHT/DENSITY

INTRODUCTIONThe wicking technique has been used to determine the surface energy components of solids[1-7]. Generally, thereare two wicking processes in practice, i.e. thin layer wicking and column wicking. A comparison of the twowicking techniques made by van Oss et al.[2], shows that column wicking has a problem of showing differentpacking density due to some kinds of powder materials, i.e. clay can not give good repacking reproducibility[2].But thin layer wicking has a problem in sample…     

USE OF ANNULAR ARTIFICIAL PUPIL IN THE DETERMINATION OF MODULATION TRANSFER FUNCTION OF THE EYE

According to Bef. [1] primary spherical aberration of the schematic eye would be com-pletely absorbed by an annular aperture when its obstruetion ratio ∈≥0.60. Consequently thecontrast sensitivity function, T_(cs), determined with the use of such an annulus, T_(cs) (A), is theMTF of the retina-brain system, T_(rh), weighted by the MTF of the annulus, T_⊙.T_(rh) thus obtain-ed can be used to determine the MTF of the eye, T_e. Annular apertures of various sizes andobstruction ratios used for the determination of T_e have been analysed. It is shown that thereare several factors other than incomplete absorption of primary spherical aberration thatwould prevent the use of annular pupil to derive T_(rb) under unrestrained conditions. This is dueto the fact that the apparent T_⊙'s of annuli used in the actual determination of T_(cs)(A) usual-ly deviate from the theoretical T_⊙'s for the passive eye to different extents. However, it isfound that the T_⊙ for annulus of o.d.=2.7 mm and ∈= 0.60 conforms more or less to thetheoretical T_⊙ and can be used to derive reasonably accurate T_e(2.7). It is also possibleto estimate T_e(>2.7) from T_e(2.7) by some empirical correction.     

THE CRYSTAL STRUCTURE OF BAYLEYITE

The bayleyite crystallizes in monoclinic space group C_2~5h-P2_1/c with a=6.499(1), b=15.235(5), c=26.513(6), β= 92.92(2)°, Z=4. Intensities of 3430 independent reflections are collected with diffractometer using MoKα radiation. The crystal structure has been solved by the Patterson method and refined by block least square refinement for positional parameters and isotropic temperature factor of non-hydrogen atoms. The final R factor is 0.038.The result of crystal structure analysis shows that the structure consists of discrete [UO_2(CO_3)_3]~(4-) ions and Mg~(2 ) cations are between slab-like units, but they are not in a slablike unit. Its crystal struture is different from that of liebigite which was determined by Appleman. Complexes and cations between slab-like units and in a slab-like unit are connected by hydrogen bonds formed by water molecules.     

INFLUENCES OF WATER-SOLUBLE CATIONIC MONOMERS ON THE POLYMERIZATION RATE IN THE INVERSE EMULSION

This investigation deals with the free radical polymerization both of (2-methacryloyloxy-ethyl) trimethyl ammonium chloride (QACEMA) and of diallyldimethyl ammoniumcbloride (DADMAC) in inverse emulsion. The influences of some factors, such as theconcentration of monomers, initiator and emulsifier are discussed. The polymerization rateequations of above two monomers can be written as follows:R_p= k[M]~(1.21) [I]~(0.82) [E]~(0.57) (for QACEMA)R_p= k'[M]~(1.34) [I]~(0.90)[E]~(0.62)(for DADMAC)     

STUDIES ON GRAFT COPOLYMERIZATION OF DL-LACTIDE ON CORN STARCH AND BIODEGRADABILITY OF THE COPOLYMERS

1.INTRODUCTIONItiswellknownthataliphaticpolyestershaveahighlevelofbiodegradabilityandstarchwasakindoftotallybiodegradablenaturalpolymermaterial[1,2].Thebiodegradabilityofthealiphaticpolyesters/starchgraftcopolymerswereinvestigatedextensively[3-6].Thepresentpaperrelatestoaprocedureforpreparingastarch/D,L-lactidegraftcopolymer,akindofhydrophobic,totallybiodegradableproducthavinggoodwater-resistanceandmechanicalproperties.ThegraftcopolymersweresynthesizedbyreactingD,L-lactidewithcornstarchi…     

REMOVAL OF GLUCORAPHENIN FROM THE EXTRACT OF RADISH PIGMENT BY ANION EXCHANGE RESIN 201×7

1NTRODUCTIONRadishredpigment,anewlydevelopednaturalpigmentwhichmainispelargonidin,hasbeenwidelyusedforfood,beverage['Jetc.BecausethereisglucoraphenininRadish,anditcanbehydrolizedbysinapinease,andthenapeculiartastewhichisdifficulttoremovewasappearedthusthepigmentwash.it.d[2].ZhouXiaohua.t.l[3)reportedamethodforadsorptionandseparationofRadishredpigmentbyD61canonionexchangeresin,buttheconsumptionoftheresinwasverylarge.GlucorapheninwasanionanditscontentisverylowcomparedwiththeRadishredpigme…     

ENHANCEMENT OF THE SALT EFFECT ON THE CONFORMATION OF M. L. DNA MOLECULES BY METHYLATION

Methylated Micrococcus luteus DNA (M. L. DNA) in which the DNA methylation level was 2.39% was prepared by using Hhal DNA methylase. (The natural M. L. DNA is completely unmethylated.) The [θ]_(275) value of M. L. DNA was decreased and the —[θ]_(220-250) value was increased with increasing concentration of MgC1_2. The UV spectra of M. L. DNA at different concentration of MgCl_2 showed that a hypochromisity happens at 260nm with increasing concentration of MgC1_2. The heat-releasing of M. L. DNA also increased with increasing concentration of MgC1_2. A11 these results showed that the M. L. DNA molecules tend to shrink in space, The difference between methylated DNA and unmethylated DNA was compared. The sensitivity of methylated DNA to MgC1_2 is 40—70 fold higher than that of the unmethylated M. L. DNA.     

STUDY ON THE KINETICS OF POLYMERIZATION OF MMA BY COPPER (Ⅱ) CHELATING RESINS

The polymerization of MMA initiated by copper (Ⅱ) chelating resins/CCl4 system was studied. From the kinetic data, the kinetic equation of polymerization can be expressed asRp = Ke-56400/RT[MMA]1.57[CCl4]m[RESIN-Cu]0.18where m:3-4. 5,when [CCl4] 0. 1-6. 93M. The free radical polymerization mechanism is proposed. The primary radicals are formed by the process of complexation-chlorine transformation among the copper(Ⅱ)chelating resin,CCl4 and methacrylate.     

THE SYNTHESIS OF MODIFIED DIPHENYL OXIDE RESIN

1. INTRODUCTION Poly (diphenyl oxide) (DPO) resins are a series of heat-resisting thermosetting resins. In 1960s, the West House Company applied them to make H class insulting materials and got an extensive use successfully [1]. But due to the three main…     

STUDIES ON THE SORPTION OF MACROPOROUS PHOSPHONIC ACID RESIN FOR LANTHANUM

Thesynthesischaracterizationsorptionbehaviorandmechanismofchelateresinfornoblemetalions[1,2]andlanthanum[3]havebeenpublishedbytheauthorandhiscoworkers.Macroporousphosphonicacidresin(PAR)containsafunctionalgroup[-PO(OH),],whichpossessnotonlyprotonthatcanexchangewithcanon,butalsoanoxygenatomoffunctionalgroupthatcancoordinatedirectlywithmetal.Inrecentyears,muchresearchhasbeenmadeonusingPAR[4-7].adsorbingcertainmetalions.Inthispaper,thesorptionpropertiesofPARforLa(III)wereinvestigated.Aloto…