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71.
这座建筑是大学的语言教育中心,设有500台计算机、影像和音响系统,主要用于语言教学、留学生教学及国际交流活动。作为建筑“外皮”的性能,设计满足以下三点要求:①充分考虑减少计算机显示器的光反射,营造照度对比小的均质柔和的光环境。②在影像放映时,光环境可渐变调节。③适度的外墙散热功能。教室分别布置在南北两侧,南面的波纹玻璃和合成树脂板材形成双层表皮,中间设计有可调控百叶,能根据日照的入射角度调节;夏季可排热,冬季则可让阳光照射进室内,从而既可获得柔和均质的采光效果又可对热负载进行有效的控制。在建筑北侧满铺的玻璃砖…  相似文献   
72.
A simple technique for splicing optical fibres is reported. The technique utilises a self-aligning ceramic capillary with inner dimensions slightly larger than the optical fibre. An average loss of below 0.1 dB is obtained for splices in graded-index and single-mode fibres with a 50 and 10 ?m core diameter, respectively.  相似文献   
73.
The configurational sequences of 1,2-unit in a series of hydrogenated syndiotactic 1,2-polybutadienes were investigated in relation to the sequence distribution of 1,2- and 1,4-units. The signals at 10.20–10.94 ppm were assigned to the methyl carbons in the isolated 1,2-unit, the 1,2-1,2 dyad sequence flanked by 1,4-unit, and the 1,2-1,2-1,2 triad sequence, in order of increasing magnetic field. The splittings due to the configurational sequences were observed in the signals, reflecting the dyad and triad sequences of the 1,2-unit, which were assigned by considering the relative intensity of the signals and also the chemical shifts of model polymers.  相似文献   
74.
Calluses were induced from the stem and the root tissues of horse radish plantlets. Cell aggregate selections were carried out on them to obtain a cell line with higher peroxidase activity, and the isozyme patterns of the peroxidases from the cultured cells and their utility values as a clinical diagnostic reagent were investigated. The repetition of the cell aggregate selection resulted in increases in peroxidase activities in each generation of selection; about eleven fold in the 13th generation of selection from the stem tissues and about nine fold in the 13th generation from the root tissues. One of the cell lines (N5K6-S), originally derived from the stem tissues, after selectin showed a tenfold increase in peroxidase activity within two weeks of culture in a liquid medium. The value as a clinical diagnostic reagent of peroxidases extracted from the N5K6-S cells was estimated to be equivalent to those already commercially available for the same purpose. There were significant differences in the isoenzyme patterns of the peroxidases from root tissues and those from cultured cells. From these results, the possibility of commercial production of peroxidase utilizing plant tissue and cell culture techniques was discussed.  相似文献   
75.
The OSE Project aims at developing the technology to utilize solar energy for heating, cooling and hot water supply on the basis of various technology for energy conservation in buildings. For the first step of this project a solar heating and cooling system with flat plate collectors and absorption refrigeration machine was installed in a house in 1974. This paper reports outlines of the system and operating results.  相似文献   
76.
Advances in the digital network society require both higher density and higher transfer rates in all sorts of storage systems. Especially in optical recording, the trend toward higher density and larger capacity requires novel surface-recording technologies that can drastically diminish head-to-medium spacing, resulting in an improvement in spatial resolution and, finally, a higher recording density. To this end, we have already proposed a novel contact optical head slider that is able to almost cancel the suspension load by generating hydrodynamic pressure, thus realizing a lower net contact force. Evaluating the dynamic contact force is requisite in realizing its stable sliding operation and higher signal readout performance. In this study, a continuous acoustic emission (AE) signal was utilized to detect the dynamic contact force. AE signal modulation was compared with the applied out-of-plane acceleration on a medium generated by a spindle combined piezo-electric actuator. It was clarified that the detected AE modulation amplitude was approximately proportional to the applied acceleration, and that utilizing AE modulation will be a useful method for evaluating dynamic contact force.  相似文献   
77.
This paper proposes a new proof-based approach to safe evolution of distributed software systems. Specifically, it extends the simple certification mechanism of proof-carrying code (PCC) to make it interactive and probabilistic, thereby devising interactive proof-carrying code (iPCC). With iPCC, a code consumer is convinced, with overwhelming probability, of the existence and validity of a safety proof of a transmitted code through interaction with a code producer. The iPCC mechanism theoretically solves the problem of proof explosion with PCC and can be used to efficiently prove a greater variety of safety properties that may require longer proofs. Technically, the class (PSPACE) of safety properties that are efficiently provable by iPCC is larger than the class (NP) efficiently provable by PCC. To illustrate the power of iPCC, this paper demonstrates that the verification of certain basic safety properties of typical machine instruction codes needs co-NP-complete computation, and shows how these safety properties can be efficiently verified by the iPCC mechanism.This is an extended and revised version of Tsukada (2001a), which appeared in the Proceedings of the 2000 International Symposium on Principles of Software Evolution. A preliminary version was also presented at the International Conference on Advances in Infrastructure for Electronic Business, Science, and Education on the Internet (Tsukada, 2001b).  相似文献   
78.
Shiina T  Yoshida K  Ito M  Okamura Y 《Applied optics》2005,44(34):7407-7413
An in-line type compact micropulse lidar (MPL) with an annular beam was developed for low-altitude cloud measurement. An optical circulator and a couple of axicon prisms for an annular beam were installed on the lidar optics. The advantage of using the in-line MPL is its ability to obtain a near-range measurement with a narrow field of view of 0.1 mrad and to obtain a depolarization measurement of the orthogonally polarized echoes caused by ice crystals of a low-altitude cloud. The total insertion loss of the lidar optics was 3 dB. Detectors such as avalance photodiode detectors can be operated in an analog mode near the breakdown voltage because of the high isolation of the optical circulator. The ideal lidar echo variation from the nearest distance was verified by measuring the mountain echoes at various distances. The depolarization measurement of a low-altitude ice cloud was also demonstrated.  相似文献   
79.
Polyamides having epoxy groups and their ring-opening derivatives were prepared and characterized, and some of their properties were investigated. Reaction conditions for the low-temperature polycondensation of cis-2,3-epoxysuccinyl chloride (ESC) with aromatic diamines and the interfacial copolycondensation of ESC and adipyl chloride (AC) with aromatic diamines were established to obtain a high molecular weight polyamide having epoxy groups. In addition, the ring-opening reactions of the epoxy groups in the polyamides were carried out with various amines in order to obtain polyamides having hydrophilic pendent groups such as amino and hydroxyl. It was found that the polyamides prepared by ring-opening reaction of the epoxy group with ethylenediamine (EDA) or ethanolamine (EA) had a higher affinity for moisture than those with hexamethylenediamine (HMD) or n-butylamine (n-BA), which might be ascribed to the distance of hydrophilic groups from the polyamide chain. Those polyamides having hydrophilic pendent groups decomposed upon heating at less than 200°C.  相似文献   
80.
Sequence distribution of styrene-butadiene copolymer (SBR) was investigated by ozonolysis-g.p.c. All the double bonds of butadiene units in SBR were cleaved by ozonolysis in methylene chloride at ?30°C, followed by reduction degradation to alcohol with lithium aluminium hydride. The g.p.c. of the ozonolysis products observed with a u.v.-detector showed the peaks corresponding to styrene sequences and styrene-1,2 sequences. Hot- and cold-emulsion SBR samples contained short sequences consisting of 1 to 4 styrene units and 1,2 styrene units respectively. The average sequence length of cold-emulsion SBR was slightly longer than that of hot-emulsion SBR. A partial block SBR prepared by solution polymerization contained short styrene sequences of 1 to 5 units and long sequences having a broad distribution of MwMn = 1.6 with the maximum around 35 units. The styrene sequences containing the 1,2 unit was scarcely observed in this sample.  相似文献   
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