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1.
The structure of the title compound, C15H27N2+·ClO4?, consists of a monoprotonated sparteinium cation and a perchlorate anion. The two tertiary N atoms of the cation, one perchlorate O atom and a H atom form a bifurcated hydrogen bond, the four hydrogen‐bonding atoms being nearly in the same plane.  相似文献   
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A Peak Identification and Activity Determination (PIAD) computer program has been developed. A new concept of peak significance is introduced and a great change has been made to the currently used associated gamma lines technique in calculating the confidence index; confidence factor is also given to the gamma line of a nuclide that is not seen in the spectrum. The program is written in Fortran IV under the operating system of RSX-11M.  相似文献   
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For this study, a 4 stage electrical low pressure impactor was designed to measure the real‐time size distribution of diesel particulate matter (DPM). For the performance evaluation, sodium chloride (NaCl) particles and dioctyl sebacate (DOS) particles were used. After evaluating the collection efficiency of each stage of the impactor, the size distributions of test particles were estimated using electrical current data and their inversion algorithm, and this was found to agree with the results obtained by a scanning mobility particle sizer (SMPS). For measurement of DPM, a common‐rail direct injection (CRDI) diesel engine, for engine speeds of 1,200 rpm and 1,500 rpm at 2.7 kgf·m, was used. Therefore, it was found that the size distribution of the DPM could be easily obtained, with the currents measured by the impactor and the data inversion algorithm, in less than 5 seconds. Furthermore, the effective density of the DPM could be obtained using the calculated results and the SMPS data.  相似文献   
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In the title complex, [Cu(N3)2(C15H26N2)], the Cu atom is surrounded by the two N atoms of the chelating (?)‐α‐isosparteine ligand and another two N atoms from the two azide anions, forming a distorted CuN4 tetrahedron. The two azide anions are terminally bound to the CuII atom, and the dihedral angle between the Nsparteine—Cu—Nsparteine and Nazide—Cu—Nazide planes is 50.0 (2)°.  相似文献   
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Organic structure‐directing agents (OSDAs), such as quaternary ammonium cations and amines, used in the synthesis of zeolites and related crystalline microporous oxides usually end up entrapped inside the void spaces of the crystallized inorganic host lattice. But none of them is known to form direct chemical bonds to the framework of these industrially important catalysts and adsorbents. We demonstrate that ECR‐40, currently regarded as a typical silicoaluminophosphate molecular sieve, constitutes instead a new family of inorganic‐organic hybrid networks in which the OSDAs are covalently bonded to the inorganic framework. ECR‐40 crystallization begins with the formation of an Al–OSDA complex in the liquid phase in which the Al is octahedrally coordinated. This unit is incorporated in the crystallizing ECR‐40. Subsequent removal of framework‐bound OSDAs generates Al‐O‐Al linkages in a fully tetrahedrally coordinated framework.  相似文献   
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Given α ∈ [0, 1], let h α (z):= z/(1 - αz), z ∈ D:= {z ∈ D: |z| < 1}. An analytic standardly normalized function f in D is called close-to-convex with respect to h α if there exists δ ∈ (-π/2, π/2) such that Re{eiδ zf′(z)/h α (z)} > 0, z ∈ D. For the class ? (h α ) of all close-to-convex functions with respect to h α , the Fekete-Szegö problem is studied.  相似文献   
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