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891.
Matrix-type composite particle for controlled drug release can readily be prepared through a totally dry process by simple anaerobic mechanical vibration of mechanoradical-containing ethylcellulose (EC) with theophylline powder due to occurrence of collision-induced radical-radical coupling reaction to form interparticle matrices, as well as the formation of interparticle network when solid-state vinyl monomer was further added.  相似文献   
892.
In the paper [KW2] we introduced a new type of Selberg zeta function for establishing a certain identity among the non-trivial zeroes of the Selberg zeta function and of the Riemann zeta function. We shall call this zeta function a higher Selberg zeta function. The purpose of this paper is to study the analytic properties of the higher Selberg zeta function z(s), especially to obtain the functional equation. We also describe the gamma factor of z(s) in terms of the triple sine function explicitly and, further, determine the complete higher Selberg zeta function with having a discussion of a certain generalized zeta regularization.Work in part supported by Grant-in Aid for Scientific Research (B) No.11440010, and by Grant-in Aid for Exploratory Research No.13874004, Japan Society for the Promotion of Science  相似文献   
893.
894.
Carbazole-linked [60]fullerene adducts were successfully prepared by the Bingel reactions using carbazole derivatives bearing one or two ethyl malonate moieties. In the latter cases, specific bisadduct regioisomers were obtained, depending on the spacer unit between two ethyl malonate moieties. [reaction: see text]  相似文献   
895.
A non-restrictive and non-contact respiratory movement monitoring system that finds the boundary between chest and abdomen automatically and detects the vertical movement of each part of the body separately is proposed. The system uses a fiber-grating vision sensor technique and the boundary position detection is carried out by calculating the centers of gravity of upward moving and downward moving sampling points, respectively. In the experiment to evaluate the ability to detect the respiratory movement signals of each part and to discriminate between obstructive and central apneas, detected signals of the two parts and their total clearly showed the peculiarities of obstructive and central apnea. The cross talk between the two categories classified automatically according to several rules that reflect the peculiarities was 15%. This result is sufficient for discriminating central sleep apnea syndrome from obstructive sleep apnea syndrome and indicates that the system is promising as screening equipment. © 2005 The Optical Society of Japan  相似文献   
896.
Patterning of semiconductor surfaces is an area of intense interest, not only for technological applications, such as molecular electronics, sensing, cellular recognition, and others, but also for fundamental understanding of surface reactivity, general control over surface properties, and development of new surface reactivity. In this communication, we describe the use of self-assembling block copolymers to direct semiconductor surface chemistry in a spatially defined manner, on the nanoscale. The proof-of-principle class of reactions evaluated here is galvanic displacement, in which a metal ion, M+, is reduced to M0 by the semiconductor, including Si, Ge, InP, and GaAs. The block copolymer chosen has a polypyridine block which binds to the metal ions and brings them into close proximity with the surface, at which point they undergo reaction; the pattern of resulting surface chemistry, therefore, mirrors the nanoscale structure of the parent block copolymer. This chemistry has the added advantage of forming metal nanostructures that result in an alloy or intermetallic at the interface, leading to strongly bound metal nanoparticles that may have interesting electronic properties. This approach has been shown to be very general, functioning on a variety of semiconductor substrates for both silver and gold deposition, and is being extended to organic and inorganic reactions on a variety of conducting, semiconducting, and insulating substrates.  相似文献   
897.
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899.
A micro-reactor was utilized for continuous and controlled CdSe nanocrystal preparation. Effects of reaction conditions on optical properties of the nanocrystals were investigated; in this current system, rapid and exact temperature control of the micro-reactor was beneficial for controlling particle diameter and reproducible preparation of particles; additional effort was made towards narrower particle-size distributions.  相似文献   
900.
The combination of the water-soluble radical initiator, 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride (VA-044), and surfactant, cetyltrimethylammonium bromide (CTAB), was found to be the most suitable condition for the effective direct synthesis of useful active thioesters (pentafluorophenyl thioesters) in water.  相似文献   
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