Cry stallinity

At higher frequencies (above 200 cm ) the vibrational spectra for fullerenes and their cry.stalline solids are dominated by the intramolecular modes. Because of the high symmetry of the Cgo molecule (icosahedral point group Ih), there are only 46 distinct molecular mode frequencies corresponding to the 180 6 = 174 degrees of freedom for the isolated Cgo molecule, and of these only 4 are infrared-active (all with Ti symmetry) and 10 are Raman-active (2 with Ag symmetry and 8 with Hg symmetry). The remaining 32 eigcnfrequencies correspond to silent modes, i.e., they are not optically active in first order. 

For the identification of citronellal, the semi-carbazone is the easiest cry stalline compound to prepare. It results if an alcoholic solution of citronellal be well-shaken with a solution of semi-carbazide hydrochloride and acetate of sodium. It is purified by recrystallisation from a mixture of chloroform and petroleum ether, and then melts at 84°. It also forms a well-defined naphthocinchoninic acid, which is prepared in the same manner as the corresponding citral compound. It melts at 225°. 

Tsao,K.Y.,andBusta,H.H, Low Pressure CVD of Tungsten on Poly cry stalline and Single-Crystal Silicon viathe SiliconReduction, J. Electrochem. Soc., 131(ll) 2702-2708 (Nov. 1984)... 

CVD is used in silicon production in two major areas 1) in the production of ultra-pure silicon from which single-crystal ingots are made, and 2) in the preparation of epitaxial and poly cry stalline films. 

Hard, waxlike, crys-stalline fibers may be cold drawn above M.W. 90002-10... 

Methanol Oxidation at a Smooth Polished Poly cry stalline Platinum Electrode O 3.3—The Electrochemical Reduction of CO[sub(2)]... 

CARBORANE. A cry stalline compound composed of boron, carbon, and hydrogen. It can be synthesized in various ways, chiefly by the reaction of a borane (penta-or deca-) with acetylene, either at high temperature in the gas phase or in the presence of a Lewis base. Alkylated derivatives have been prepared. Carborancs have different structural and chemical characteristics and should not be conTused with hydrocarbon derivatives or boron hydrides. The predominant structures arc the cage type, the nest type, and the web type, these terms being descriptive of the arrangement of atoms in the crystals. Active research on cargorane chemistry has been conducted under sponsorship of the U.S. Office of Naval Research, http //www.onr.navy.mil/... 

The word granile comes from the Latin itrantwi. a grain, in reference in the grained structure of such a cry stalline rock. 

A final TCPP MOF of interest is found in a report that described the synthesis of M + (TCPP) (M +=Cu +, Ni +, and Pd + ) MOFs with dirhodium(II) carboxylate paddlewheel SBUs (110). The compounds were prepared via solvothermal reaction of rhodium acetate and M (TCPP) in methanol. The materials were poly cry stalline, and so structural information was deduced from powder X-ray deffraction (PXRD), elemental analysis, infrared (IR) spectroscopy, and other... 

In comparing the shear fracture surfaces of amorphous and semi-crystalline polymers, it appears that the features in both cases are quite similar (Fig. 39a -c ). This indicates that, under comparable conditions, the local stress field rather than details of the crystalline-amorphous microstructure of the polymers tested determines the operating deformation mechanism. Only secondary effects arise from the morphology of the cry stalline material. 

Gout is a metabolic disease characterized by the painful inflammation of joints. Gout is a type of arthritis- Hyperuricemia is a risk factor for gout and for the development of uric add stones in kidneys. Gout often presents as a violent attack of pain in the big toe. Less commonly, it involves the wrists, ankles, or knees. The pain spontaneously disappears after a feu days, but recurs later, with an increasing fre<)uency. Eventually, cry stalline deposits of uric acid accumulate in the joints and appear as bumps on the skin, each with a diameter of a millimeter to a few centimeters. The deposits of urate lead to erosion of the bone and to destruction of the joints. Gout can be crippling. 

Widely used as adsorbents and the components of catalysts synthetic zeolites are unique molecular sieve, which is defined by specify of their pore structure, namely, size and form of cavities of channels. During development of adsorbents and catalysts it is necessary to decide the tasks of saving of initial pore structure and connected with it adsorption ability of samples or of directed its changing with the purpose of increase of yield of necessary products, for example para - selectivity increase in the isomerisation of alkylaromatic compounds. The pore structure of zeolite-containing systems directly depends on cry stalline structure ones. 

In the present paper the change of cry stalline structure and adsorption ability of NaY zeolite is investigated with the purpose of obtaining from it the ultra stable form. An aqueous solution hexafluorosilicate is used as the agent of dealumination. 

In earlier times, when relatively few pure organic chemicals were known, new compounds were named at the whim of their discoverer. Thus, urea (CH4N2O) is a cry.stalline substance isolated from urine morphine (C17H19NO3) is an analgesic (painkiller) named after Morpheus, the Greek god of dreams and barbituric acid is a tranquilizing agent named by its discoverer in honor of his friend Barbara. 

Propylparaben, HF. Propyl />-hydroxybcn/.oatc. or propylparaben. occurs as a white cry.stalline powder that is slightly soluble in water but soluble in most organic solvents. It is used as a preservative, primarily to retard yeast growth. Pmpylparabcn sodium is a water-.soluble sodium salt of the 4.phcnol group. The pH of solutions of propylparaben. sodium is basic (pH 10). 

Sodium Benzoate, NF. Sodium ben/oaic is a white cry.stalline solid that is. soluble in water and alcohol. It is used ns a prc.scrvativc in acidic liquid preparations in which benzoic acid is relc.-iscd. 

Terbina/ine Hydrochloride, USP. ( )-Af-(6.6-di-iicihy l 2.hepicn-4-ynyl)-Af-methyl-1- naphthalcne-methana- ln llydrochlolide (Lamisil) is an off-white cry.stalline ma-Aiul that Is soluble in polar organic solvents such as metha-... 

Oxiconazole Nitrate, USP. (Z)-l-(2.4-dichloruphe-nyl)-2-(l W-imidazol-l-yl)elhanone-0-[2.4-dichlorophenyl) meiiiyljoxime inononiiraie (Oxislal) is a while cry.stalline nitric acid salt. It is used in cream and lotion do.sagc forms in 1% concentration for the treatment of tinea pedis, tinea corporis, and tinea capitis. 

Methimazole, USP. Mcthimazole, l-methylimidazolc-2-thioI (Tapazolc), occurs as a white to off-white, cry.stalline powder with a characteristic odor and is freely soluble in water. A 2% aqueous solution has a pH of 6.7 to 6.9. It should be packaged in well-closed, light-resistant containers. 

Diphenhydramine Hydrochloride, USP. Diphenl dramine hydrochloride. 2-(diphcnylmcthoxy)-Af.Af-dinictb.il cthanamine hydrochloride (Benadryl), has an oily. Iipid-.s>) able free base available as the bitter-tasting hydrochluriJ salt, which is a. stable, white cry.stalline powder soluble n water (I I). alcohol (1 2). and chloroform (1 2). The salt b. a pK value of 9. and a 1% aqueous solution has a pH fi about 5. 

DIphenylpyrallne Hydrochloride. USP. Dipheaylp)T-aline hydrochloride. 4-(diphenylmethoxy)-l-methylpipen-dine hydrochloride (Hispril. Diafen) occurs as a while m slightly off-white cry.stalline powder that is soluble in water or alcohol. Diphenylpyraline is structurally related to ifi-phenhydramine with the aminoalkyl side chain incotporated in a piperidine ring. It is a potent antihistaminic. oad ihc usual dose is 2 mg 3 or 4 times daily. The hydrochloride b available as S-mg sustained-release capsules. 

Pheniramine Maleate. Pheniramine maleatc, 2- -[2-dimethylaminoethyl ben/yl]pyridine bimalcatc (Trimeton, Inhiston). is a white cry.stalline powder, with a faint amine-like odor, that is soluble in water (1 5) and very soluble in alcohol. 

Cetirizine, USP. Cctirizinc. 2-(4- (4-chloruphenyl phenylmcihyl -l-pipcra7.inyl ethoxy acetic acid (Zyrtcc). is a racemic compound available as a white cry.stalline powder that is water soluble. 

Omeprazole. Omeprazole. 5-mcihoxy-2-(((4-incthox -.3.5-dimelhyl-2-pyridinyl)melhyl)sulfmyl)-IW-benzimidj-zoic (Loscc). is a while to off-white cry.stalline powder with, very slight solubility in water. Omeprazole is an amphuleric compound (pyridine N. pK 4.l.3 bcnzimida/ole N-H.pK.. 

Codeine Sulfate, USP. Ctxleine sulfate is prepared by neutralizing an aqueous suspension of codeine with diluted sulfuric acid and then effecting crystallization. It cK Curs us white cry.stals. usually needle-like, or as a white cry.stalline powder. The salt is efflorescent and light sensitive. It is. soluble in water (1 30. 1 6.S at 80°). much less soluble in alcohol (1 1.280). and insoluble in ether or chloroform. This salt of codeine is prescribed frequently but is not as suitable os the pho.sphate for liquid preparations. Solutions of the sulfate and the phosphate are incompatible with alkaloidal reagents and alkaline sub.stances. 

Menadione sodium bisuifate occurs as a white, cry.stalline. odorIe.ss powder. One grunt of it dissolves in about 2 mL of water, and it is slightly soluble in alcohol. It decomposes in the pre.sence of alkali to liberate the free quinonc. 

Niacinamide, U5P. Niacinamide, nicotinamide, nicotinic acid amide, is prepared by the amidation of esters of nicotinic acid or by pa.ssing ammonia gas into nicotinic acid at 320°C. Nicotinamide is a white cry.stalline powder that is odorless, or nearly so, and bitter. One gram is soluble in about I mL of water, I.S mL of alcohol, and about 10 mL of glycerin. Aqueous solutions aie neutral to litmus. For occurrence, action, and uses, see nicotinic acid. Niacinamide has pK values of O.. and 3.35. 

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