浅议水利在运河枣庄段产业结构优化中的作用

运河枣庄段是京杭运河的重要组成部分,文化资源丰富,经济发展潜力巨大。近年来,在山东省＂加快鲁南经济带规划建设＂的战略部署下,枣庄市着眼于全市经济结构战略性调整,把沿运经济带开发建设和运河水文化建设作为构筑枣庄发展优势的新突破,作为加快资源型城市经济转型的新举措,以运河为载体,以水利为保障,提出了打造＂江北水乡·运河古城＂城市名片,促进了运河枣庄段产业结构优化和可持续发展,使古老运河焕发出了勃勃生机。     

Conducting polyaniline-nano-TiO2 composites for smart corrosion resistant coatings

Coatings prepared from polyaniline-nano-TiO₂ particles synthesized by in situ polymerization were found to exhibit excellent corrosion resistance much superior to polyaniline (PANI) in aggressive environments. The corrosion studies were carried out on steel plates coated with these formulations containing 10 wt% polyaniline prepared with different concentrations of nano-TiO₂. The electrochemical impedance spectroscopy was studied at periodic intervals during exposure to hot saline (65 °C) conditions for prolonged durations over a period of 90 h. The open circuit potential (OCP) was found to shift with time from −0.38 V SCE to more anodic side (−0.2 V SCE) much above that of bare steel (−0.5 V SCE). The presence of nano-TiO₂ was found to be vital in the prevention of corrosion and the shift of OCP to anodic side. From these data, one could envisage more than 100 times improvement in the corrosion resistance especially for polyaniline prepared with 4.18 wt% nano-TiO₂. The exceptional improvement of performance of these coatings has been associated with the increase in barrier to diffusion, prevention of charge transport by the nano-size TiO₂, redox properties of polyaniline as well as very large surface area available for the liberation of dopant due to nano-size additive.     

Epoxy powder coatings containing polyaniline for enhanced corrosion protection

Incorporation of polyaniline (PANI) in epoxy type powder coating formulations has not been attempted earlier. Using specific grade of PANI with low doping, it can be incorporated in epoxy powder coating formulations by twin screw extrusion process. The powder formulations were deposited on steel substrates by electrostatic spray coating at −60 kV and baked at 140 °C for 20 min. These were extensively tested for corrosion resistance by exposure to hot saline conditions followed by electrochemical impedance spectroscopy and also salt spray testing. PANI incorporated coatings showed no deterioration even after 1400 h of hot (65 °C) saline treatment. The coatings intentionally scratched also exhibited self healing property and there was no rust formation even after prolonged exposure to hot saline conditions. These results could be explained on the basis of additional crosslinking due to PANI, as confirmed by DSC results, which gave rise to improved barrier property and self healing was associated with the scavenging of ions by PANI which prevented corrosion of the underlying substrate.     

Vacuum system of SST-1 Tokamak

Vacuum chambers of Steady State Superconducting (SST-1) Tokamak comprises of the vacuum vessel and the cryostat. The plasma will be confined inside the vacuum vessel while the cryostat houses the superconducting magnet systems (TF and PF coils), LN₂ cooled thermal shields and hydraulics for these circuits. The vacuum vessel is an ultra-high (UHV) vacuum chamber while the cryostat is a high-vacuum (HV) chamber. In order to achieve UHV inside the vacuum vessel, it would be baked at 150 °C for longer duration. For this purpose, U-shaped baking channels are welded inside the vacuum vessel. The baking will be carried out by flowing hot nitrogen gas through these channels at 250 °C at 4.5 bar gauge pressure. During plasma operation, the pressure inside the vacuum vessel will be raised between 1.0 × 10^?4 mbar and 1.0 × 10^?5 mbar using piezoelectric valves and control system. An ultimate pressure of 4.78 × 10^?6 mbar is achieved inside the vacuum vessel after 100 h of pumping. The limitation is due to the development of few leaks of the order of 10^?5 mbar l/s at the critical locations of the vacuum vessel during baking which was confirmed with the presence of nitrogen gas and oxygen gas with the ratio of ～3.81:1 indicating air leak. Similarly an ultimate vacuum of 2.24 × 10^?5 mbar is achieved inside the cryostat. Baking of the vacuum vessel up to 110 °C with ±10 °C deviation was achieved with a net mass flow rate of 0.8 kg/s at 1.5 bar gauge inlet pressure and supply temperature of 230 °C at the heater end. Also during gas feed system installation, the pressure inside the VV was raised from 3.01 × 10^?5 mbar to 1.72 × 10^?4 mbar by triggering a pulse of lower amplitude of 25 voltage direct current (VDC) for 100 s to piezoelectric valve. This paper describes in detail the design and implementation of the various vacuum subsystems including relevant experimental results.     

Hierarchical amphiphilic high-efficiency oil–water separation membranes from fermentation derived cellulose and recycled polystyrene

A high-efficiency separation of oil and water can be achieved by using specially designed amphiphilic porous membrane. However, the preparation of such membranes often involves complex multistep chemical processes. Herein, we report an amphiphilic composite membrane (polystyrene [PS]/bacterial cellulose [BC] membrane) consisting of hydrophobic recycled PS and hydrophilic BC, fabricated by a facile in situ fermentation process. Not only these membranes exhibit a combination of contrasting wettability but also comprise of a hierarchical network of microfibers and nanofibers, which makes them ideal for oil–water separation. The structural and morphological properties of as-produced BC, recycled PS membrane, and PS/BC composite membrane were studied by Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. The ability of the membranes to separate oil and water was tested by using an emulsion of hexane-in-water as the feed and the collected filtrates were characterized by optical microscopy and UV–Vis spectroscopy. PS membranes were unable to separate oil and water, while the PS/BC membrane efficiently separated water from the emulsion. PS/BC composite membranes showed a high water recovery of more than 90%, against only 57% recovery shown by BC. Mechanisms of oil–water separation for each membrane are discussed. The reusability of the PS/BC composite membrane was also demonstrated.     

Effect of Feedstock Powders on the Microstructural and Electrical Characteristics of 8 mol% Yttria-Stabilized Zirconia Plasma-Sprayed Coatings

Plasma-sprayed coatings of 8 mol% yttria-stabilized zirconia (YSZ) were fabricated using the feedstock powders obtained from co-precipitation (PPT) and spray-drying (SD) processes. Particle size and the specific mass (SM) of the feedstock powder were found to be the critical parameters that influence the microstructural and electrical properties of the coatings. While dense and larger particle-sized PPT powder resulted in a porous microstructure, dense coatings were obtained for SD powders with relatively lower SM. Electrical conductivity values of SD-coatings were found to be 30% higher than that of PPT-coatings. Electrical conductivity values of plasma-sprayed PPT-coatings improved significantly on decreasing the particles size. However, the size effect was only subtle in the case of SD coatings. PPT-coatings fabricated from smaller particle-sized powders had the necessary electrical conductivities appropriate for solid oxide fuel cell electrolyte applications.     

Nitrogen Gas Heating and Supply System for SST-1 Tokamak

Steady State Tokamak (SST-1) vacuum vessel baking as well as baking of the first wall components of SST-1 are essential to plasma physics experiments. Under a refurbishment spectrum of SST-1, the nitrogen gas heating and supply system has been fully refurbished. The SST-1 vacuum vessel consists of ultra-high vacuum (UHV) compatible eight modules and eight sectors. Rectangular baking channels are embedded on each of them. Similarly, the SST-1 plasma facing components (PFC) are comprised of modular graphite diverters and movable graphite based limiters. The nitrogen gas heating and supply system would bake the plasma facing components at 350 o C and the SST-1 vacuum vessel at 150 o C over an extended duration so as to remove water vapour and other absorbed gases. An efficient PLC based baking facility has been developed and implemented for monitoring and control purposes. This paper presents functional and operational aspects of a SST-1 nitrogen gas heating and supply system. Some of the experimental results obtained during the baking of SST-1 vacuum modules and sectors are also presented here.     

姬塬油田A区长6储层特征研究及开发效果评价

姬塬油田A区长6油藏位于鄂尔多斯盆地天环坳陷中-西部,为三角洲前缘水下分流河道沉积.发育长622、长631、长632三套含油砂体,单期砂体厚度薄(5～10 m),砂体呈北西南东向展布,砂体(油层)在纵向上、横向上连续性较差,且层间隔夹层多,属于长6超Ⅲ类油藏.2018年在该区开展小井距超前注水定向井试验,油藏整体开发效...     

Sequence characterized amplified region markers: A reliable tool for adulterant detection in turmeric powder

Turmeric powder (Curcuma longa L.), an important medicinal spice product traded internationally, is subjected to adulteration by design or default with powders of related curcumin containing wild species like Curcuma zedoaria and Curcuma malabarica leading to toxicity and poor quality of the produce. The present study aims at development of specific, sensitive and reproducible Sequence Characterized Amplified Region (SCAR) markers to detect these adulterants in traded turmeric powder. Two putative RAPD markers, ‘Cur 01’ and ‘Cur 02’, generated by random primers OPA 01 and OPE 18 were identified as C. zedoaria/C. malabarica specific by comparative RAPD analysis of genuine turmeric and market samples of turmeric powder, C. zedoaria and C. malabarica. These specific RAPD markers were cloned and sequenced. Two pairs of SCAR primers were designed from the RAPD markers ‘Cur 01’ and ‘Cur 02’, respectively. Six market samples of turmeric powder and four simulated standards besides the genuine samples were analyzed using the specific SCAR markers. Both the SCAR markers detected the presence of C. zedoaria/C. malabarica adulteration in four market samples and all the simulated standards prepared in different concentrations. The two SCAR markers developed in the study would be potentially useful for the regulatory agencies to detect C. zedoaria/C. malabarica adulteration in traded turmeric powder. The analytical strategy being very simple could be used for large scale screening of turmeric powder samples intended for export and domestic uses.     

Performance validation tests on 80 K bubble type of shields for SST-1

The 80 K thermal shields of Steady State Superconducting Tokamak (SST-1) minimize the steady state heat loads on the superconducting magnet system at 4.5 K from ambient. Uniform temperature, vacuum and cryo compatibility is desired for the 80 K shields. In order to meet these requirements, the bubble/embossed type of design concept is adopted. This design ensures lower pressure drop and better temperature uniformity within ±5 K. Special attention has been given for preventing direct radiation on the magnet system. As part of performance validation tests, a group of 80 K thermal shields have undergone rigorous testing protocols and procedures. The temperature distribution, helium leak tightness and insulation resistance tests have been carried out for SST-1 thermal shields before final assembly of the machine. The test design, procedures and results of the 80 K thermal shields will be discussed in this paper.