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1.
Downhole pumps are being used increasingly more often in low-enthalpy geothermal wells. The depth at which these pumps are installed depends on the physical and chemical characteristics of the geothermal fluid, the production flow rate, and the reservoir pressure and permeability. In this study we have investigated the factors affecting pump setting depths in low-temperature, liquid-dominated geothermal systems and defined the relationship between flow rate and pressure drawdown based on multi-rate test results. The methodology proposed was applied to the Balcova-Narlidere geothermal field, Turkey. It was found that the most important parameters for determining the capacity and setting depth of a downhole pump were flow performance, non-condensable gas concentration, and temperature. The implementation of the methodology is illustrated. 相似文献
2.
A novel phenacyl anilinium salt, N-phenacyl, N,N-dimethylanilinium hexafluoroantimonate, (PDA), has been synthesized and used as photoinitiator for cationic polymerization of cyclohexene oxide (CHO), butyl vinyl ether (BVE) and N-vinyl carbazol (NVC). Plausible mechanism of the photoinitiation involves the decay of the excited PDA with both heterolytic and homolytic cleavages of carbon-nitrogen bond. Thus, phenacylium cations formed directly or subsequent intermolecular electron transfer, respectively, initiate the polymerization. 相似文献
3.
Polymerization of β,β′-(ethylenedithio)dipropionitrile 1 IUPAC name: 4,7-dithiadecane dinitrile. with formaldehyde in the presence of sulfuric acid was carried out in order to permit the synthesis of polymides containing thioether groups. The obtained poly(amide thioether)s were characterized; they coordinate mercury (II) with a high degree of selectivity. 相似文献
4.
Abstract: In this study, an automatic three-dimensional computer-aided detection system for colonic polyps was developed. Computer-aided detection for computed tomography colonography aims at facilitating the detection of colonic polyps. First, the colon regions of whole computed tomography images were carefully segmented to reduce computational burden and prevent false positive detection. In this process, the colon regions were extracted by using a cellular neural network and then the regions of interest were determined. In order to improve the segmentation performance of the study, weights in the cellular neural network were calculated by three heuristic optimization techniques, namely genetic algorithm, differential evaluation and artificial immune system. Afterwards, a three-dimensional polyp template model was constructed to detect polyps on the segmented regions of interest. At the end of the template matching process, the volumes geometrically similar to the template were emhanced. 相似文献
5.
6.
Interaction of nitrous acid with aqua solution of poly(acrylamide) gives poly(acrylic acid) in quantitative conversion yields.
The reaction proceeds smoothly, with simultaneous evolution of nitrogen, provided that the temperature below 5 °C. The procedure
presented provides a versatile route to prepare acrylic acid-acrylamide copolymers in any desired composition, by adjusting
molar ratio of nitrous acid.
Received: 29 January 1997/Revised: 24 July 1997/Accepted: 6 August 1997 相似文献
7.
F. Banishoeib S. Fourier M. Breselge T.J. Cleij D. Vanderzande Le Huong Nguyen Niyazi Serdar Sariciftci 《Thin solid films》2008,516(12):3978-3988
Poly-(2,5-Thienylene Vinylene) (PTV) derivatives have been synthesised via the “dithiocarbamate precursor route” in good yield and satisfactory molecular weight. Structural characterisations of the conjugated PTV polymers reveal an optical band gap around 1.8 eV. Organic field effect transistors and organic based photovoltaic devices were made with the plain PTV, via a precursor approach. More specifically, solar cells were produced using a blend of the precursor PTV polymer and PCBM (1-(3-methoxycarbonyl) propyl-1-phenyl [6,6] C61) at various ratios, converted in situ in thin film. A promising power efficiency of 0.76% was achieved. 相似文献
8.
SUMMARY
High molecular weight poly (ether sulfonamide) has been prepared by condensation of 4,4'-dichlorosulfonyldiphenylether with
ethylenediamine. The reaction of potassium salt of poly (ether sulfonamide) with epichlorohydrin gives the corresponding N-glycidiyl
derivative in yield as high as 98%. The resulting polymer offers many functionalization possibilities through ring opening
of the oxirane units. Also the glycidiyl bearing polymer may act as multifunctional post-crosslinking agent for polymers carrying
hydroxy, amino or carboxyl groups.
Received: 16 February 1998/Revised version: 4 May 1998/Accepted: 7 May 1998 相似文献
9.
Hakan Cam Osman N. Ucan Niyazi Odabasioglu Ahmet Coskun Sonmez 《International Journal of Communication Systems》2010,23(1):77-90
In wireless sensor networks, data encryption and channel coding are considered together for ensuring secure and robust communication. In order to achieve this purpose, we introduce a new joint scheme, namely ‘Multilevel/Advanced Encryption Standard‐Low Density Parity Check Coded‐Continuous Phase Frequency Shift Keying (ML/AES‐LDPCC‐CPFSK)’. AES algorithm is the most powerful and widely used symmetric key cryptography in providing secure data transmission. LDPC codes have very large Euclidean distance and use iterative decoding algorithms. In this study, we have increased error performance employing multilevel structure to AES and LDPC. In all communications systems, phase discontinuities of modulated signals result in extra bandwidth requirements. CPFSK, which is a special type of continuous phase modulation, is a powerful solution for this problem. In this paper, we simulate error performance of ML/AES‐LDPCC‐CPFSK for regular LDPC codes. Simulation results are drawn for 4CPFSK, 8CPFSK and 16CPFSK over wireless cooperative sensor networks. Using this scheme, we are able to improve bit error performance, channel throughput, security level of communication and reduction in complexity compared with related schemes such as various turbo code structures. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
10.
Arne Palmaerts Thomas J. Cleij Dirk Vanderzande Almantas Pivrikas Niyazi Serdar Sariciftci 《Polymer》2009,50(21):5007-6388
Considerable interest exists in the development of novel n-type conjugated polymers, since many currently available polymer systems have insufficient electron mobility and/or electron affinity. In this work, a universal synthesis route is presented towards a new class of n-type conjugated polymers, i.e. poly(p-fluoranthene vinylene) (PFV) and its derivatives. This route is illustrated with three examples, i.e. unsubstituted PFV and functionalized hexyl-PFV and dodecyl-PFV. All polymers have been synthesized via the dithiocarbamate precursor route. Solubility was introduced by incorporation of alkyl side chains, which leads to a significantly enhanced purity and processability as compared to unsubstituted PFV. Under the applied electrochemical conditions PFV-type polymers demonstrate typical n-type behavior. Additional CELIV mobility measurements on dodecyl-PFV reveal an excellent electron mobility, μe = 1.4 × 10−4 cm2/Vs. Hence, poly(p-fluoranthene vinylene) and its derivatives are promising n-type materials for organic optoelectronic applications. 相似文献