scholarly journals Note on constitution of cyano derivates of gold

1939 ◽  
Vol 173 (953) ◽  
pp. 160-161 ◽  
Keyword(s):  
Crystal Structure ◽  
Molecular Weight ◽  
Organic Solvents ◽  
Decomposition Products ◽  
Ordinary Temperature ◽  
Suggested Structure

The results of the completed investigation of the crystal structure of di- n -propylmonocyanogold make it possible to suggest constitutions for the products of its decomposition by long standing at the ordinary temperature or by heat which are probably more correct than those already advanced (Gibson 1935, 1938). These decomposition products are “di- n -propyldicyanodigold” and aurous cyanide. Di- n -propyldicyanodigold, an auric-aurous compound, produced by loss of half the n -propyl radicals from di- n -propylmonocyanogold is insoluble in water and all organic solvents and no information regarding its molecular weight is available. It was originally proposed that its structure might be that indicated (I) based on the suggested structure of di- n -propylmonocyanogold which has now been shown to be correct.

Characteristics of fouling due to clay-organic substances in potable water treatment by ultrafiltration

1996 ◽  
Vol 34 (9) ◽  
pp. 157-164 ◽  
Author(s):  
Kim C.-H. ◽  
M. Hosomi ◽  
A. Murakami ◽  
M. Okada
Keyword(s):  
Molecular Weight ◽  
Organic Matter ◽  
Humic Acid ◽  
Fulvic Acid ◽  
Size Distribution ◽  
Ultrafiltration Membrane ◽  
Organic Substances ◽  
Decomposition Products ◽  
Microbial Decomposition ◽  
Fouling Materials

Effects of clay on fouling due to organic substances and clay were evaluated by model fouling materials and kaolin. Model fouling materials selected were protein, polysaccharide, fulvic acid, humic acid and algogenic matter (EOM:ectracellular organic matter, microbial decomposition products) and kaolin was selected as the clay material. Polysulfone membrane (MWCO(Molecular Weight Cut-Off) 10,000, 50,000 and 200,000) was used as an ultrafiltration membrane. In particular, the flux measurement of solutions containing algogenic matter used an ultrafiltration membrane of MWCO 50,000. The flux of protein and polysaccharide with coexistence of kaolin increased in the case of the ratio of MW/MWCO being greater than one, but did not increase in the case of the MW/MWCO ratio being below one. In contrast, the flux of fulvic acid and humic acid with coextence of kaolin decreased regardless of the ratio of MW/MWCO. The addition of dispersion agent and coagulant in the organic substances and kaolin mixture solution changed the size distribution of kaolin, and resulted in a change of the flux. EOM and microbial decomposition products decreased with the increase of the fraction of organic matter having molecular weight more than MWCO of membrane. The flux of the algogenic organic matter with coexistence of kaolin decreased with the increase of the amount of kaolin. It was suggested that the decline of the flux with coexistence of kaolin was due to the change of the resistance of the kaolin cake layer corresponding to the change in kaolin size distribution with charge.

scholarly journals 1,1′,3,3′-Tetramesitylquinobis(imidazole)-2,2′-dithione

IUCrData ◽  
2019 ◽  
Vol 4 (9) ◽  
Author(s):  
Jayaraman Selvakumar ◽  
Kuppuswamy Arumugam
Keyword(s):  
Crystal Structure ◽  
Molecular Weight ◽  
Solid State ◽  
Structural Analysis ◽  
Hydrogen Bonds ◽  
Cell Volume ◽  
Title Compound ◽  
Unit Cell Volume ◽  
Density Peaks ◽  
Solvent Molecules

The solid-state structural analysis of the title compound [systematic name: 5,11-disulfanylidene-4,6,10,12-tetrakis(2,4,6-trimethylphenyl)-4,6,10,12-tetraazatricyclo[7.3.0.03,7]dodeca-1(9),3(7)-diene-2,8-dione], C44H44N4O2S2 [+solvent], reveals that the molecule crystallizes in a highly symmetric cubic space group so that one quarter of the molecule is crystallographically unique, the molecule lying on special positions (two mirror planes, two twofold axes and a center of inversion). The crystal structure exhibits large cavities of 193 Å3 accounting for 7.3% of the total unit-cell volume. These cavities contain residual density peaks but it was not possible to unambiguously identify the solvent therein. The contribution of the disordered solvent molecules to the scattering was removed using a solvent mask and is not included in the reported molecular weight. No classical hydrogen bonds are observed between the main molecules.

Analysis of plasma effect on ultrahigh-molecular weight polyethylene fibers’ surface energy on strength of fibers and fiber reinforced composites

2021 ◽  
Vol 3 ◽  
pp. 42-54
Author(s):  
V. I. Mamonov ◽  
Keyword(s):  
Crystal Structure ◽  
Molecular Weight ◽  
Surface Energy ◽  
Ultrahigh Molecular Weight Polyethylene ◽  
Necessary Condition ◽  
Matrix System ◽  
Maximal Load ◽  
Ultrahigh Molecular Weight ◽  
Uhmwpe Fibers ◽  
Fiber Matrix

Completely saturated chemical bonds in ultrahigh-molecular-weight polyethylene (UHMWPE) fibers — are a reason for their low surface energy (FSE), i.e. inert properties. Elongated crystal structure of UHMWPE molecules ensures high anisotropic tensile strength of the fibers. An inertness is a problem for utilization these fibers in high-strength composites production. Surface energy (SE) difference of the fibers and a binder in fiber/matrix system hinders chemical interaction at interphase boundary and worsens fiber wettability. Increase in their FSE is a topical task for this problem decision. Necessary condition of FSE increase is the integrity of molecule structure, lying under modified surface. Low temperature, nonequilibrium plasma (LTP) treatment in a medium of argon and argon/propane mixture, used in this work for plasma activation of fibers’ surface, permits to abide by this condition. However, plasma ion bombardment during a process of activation can modify interior crystal structure and, as a result, decrease their strength. The rovings SK75 (Holland) and D800 (China) were used for study of the properties of UHMWPE fibers after plasma treatment. Activation effect on FSE, strength, and fibers’ wetting by water and epoxy binder before and after ageing was studied. Capillary wetting of the fibers by distilled water used for FSE evaluation. The data of filaments surface structure and their diameter change at maximal load, obtained by optical microscope study, were used for the analysis of FSE and epoxy matrix effect on the strength of fiber/matrix systems. Essential distinction of SK75 and D800 fibers properties is ascertained. Negative effect of fibers’ and matrix’s stiffness, as well as increased FSE of stiff fibers on the strength of fiber/matrix system is revealed.

Pteridine derivatives: novel low-molecular-weight organogelators and their piezofluorochromism

2020 ◽  
Vol 44 (8) ◽  
pp. 3382-3391
Author(s):  
Shenzheng Xu ◽  
Xiaoyu Jia ◽  
Jiaxin Lu ◽  
Lianyou Zheng ◽  
Kuo Lv ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Organic Solvents ◽  
Low Molecular Weight ◽  
Self Assembling ◽  
Conjugated Compounds ◽  
Low Molecular Weight Organogelators ◽  
Pteridine Derivatives

Here, π-conjugated compounds based on pteridine derivatives were synthesized and their self-assembling behaviors in a variety of organic solvents and piezofluorochromism were studied.

Isolation of the virus inhibitor from the root extract of Boerhaavia diffusa inducing systemic resistance in plants

1979 ◽  
Vol 57 (11) ◽  
pp. 1214-1217 ◽  
Author(s):  
H. N. Verma ◽  
L. P. Awasthi ◽  
K. C. Saxena
Keyword(s):  
Molecular Weight ◽  
Organic Solvents ◽  
Preliminary Analysis ◽  
Antiviral Agent ◽  
Systemic Resistance ◽  
Partial Purification ◽  
Root Extract ◽  
Virus Inhibitor ◽  
Boerhaavia Diffusa

An antiviral agent, active against spherical and tubular viruses in hypersensitive and systemic hosts, has been isolated from the roots of Boerhaavia diffusa. Partial purification of inhibitor by organic solvents, Sephadex gel, and protein precipitants has been achieved. Preliminary analysis indicates that the inhibitor may be a glycoprotein with a molecular weight of 16 000–20 000 daltons.

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