利用低能热解决液氨气化问题

分析三氮唑核苷生产中氨利用率低的原因 ,根据热力学原理及氨的热力学性质 ,在技改设计中利用系统低能热强制气化液氨 ,彻底解决了氨的利用问题 ,达到了节能降耗的效果。

Multi-effect distillation system for seawater desalination driven by tidal energy and low grade energy

A multi-effect distillation technology for seawater desalination driven by tidal energy and low grade energy is presented.In the system,tidal energy is utilized to supply power instead of coventional electric pumps during the operation,resulting in the decrease of dependence on steady electric power supply and a reduction in the running costs.According to the technological principle,a testing unit is designed and built.The effects of the feed seawater temperature and the heat source temperature on the unit performance are tested and analyzed.The experimental results show that the fresh water output is 27 kg/h when the heating water temperature is 65 ℃ and the absolute pressure is 25 kPa.The experimental and theoretical analysis results indicate that the appropriate heating water temperature is a key factor in ensuring the steady operation of the system.

Low temperature mechanical properties of as-extruded Mg-10Gd-3Y-0.5Zr magnesium alloy

Influence of multi-cycle cryogenic treatment and tensile temperature on microstructure, mechanical properties and fracture mechanism of as-extruded Mg-10Gd-3Y-0.5Zr magnesium alloy was investigated. The results show that there have no significant changes in tensile properties of the tested alloy after 10 d in liquid nitrogen immersion or 10 cycles of high-low temperature treatment at all test temperatures. The room temperature ultimate tensile strength increases from 398 MPa to 417 MPa after 20 cycles of high-low temperature treatments. Compared with the room temperature, the tested alloys exhibit higher tensile properties at low temperatures. At -196 °C, the yield strength and ultimate tensile strength of the as-extruded-T5 Mg-10Gd-3Y-0.5Zr alloy are 349 MPa and 506 MPa, respectively, increasing by about 18% and 27%, respectively. The transgranular cleavage fracture mechanism is observed at room temperature, while at low temperatures both ductile fracture and cleavage fracture behaviors coexist.

Effect of Ar＋, He＋, and S＋ Irradiation on n-InP Single Crystal

The irradiation effects of Ar＋, He＋, and S＋ with energy from 10 eV to 180 eV on n-InP（100） surface are analyzed by X-ray photoelectron spectroscopy and low energy electron diffraction. After irradiation on the n-InP surface, damage on the surface, displacement of the Fermilevel and formation of sulfur species on S＋ exposed surface are found and studied. Successive annealing is done to suppress the surface states introduced by S＋ exposure. However, it is unsuccessful in removing the damage caused by noble ions. Besides, S＋ ions can efficiently repair the Ar＋ damaged surface, and finally form a fine 2×2 InP surface.

Integrated utilization of low-grade thermal energy in hot coal mine

This paper explores the integrated utilization of low-grade thermal energy in hot coal mines, based on analysis of original heating, refrigerating, mine draining, bath draining and air exhaust systems, and in combination with the actual conditions of Tangkou Coal Mine in Shandong Province. It presents a set of comprehensive and integrated utilization schemes for the various different kinds of low quality heat energy. With heat pumps, the recycling of the low quality heat energy from the drainage, bathing water and the exhaust air can occur in winter, and in summer, there exists condensed heat of the refrigerating system. When in conjunction with solar collectors, the thermal utilization of solar power can be realized for the whole year. The system achieves mine drainage and bathing water purification and recycling, as well as purifying exhaust air by water spraying. It also satisfies the demands of a whole year＇s bathing heat for the coal mine, with refrigeration in summer, and heating for the ground house and shaft house in winter. It is able to integrate different kinds of low quality heat energy and low emission drainage and dust, and can replace the traditional boiler heating system. Finally, the system reduces conventional energy consumption and the amount of mine water drainage.

Quasi-Static Energy Recovery Logic with Single Power-Clock Supply

This paper presents a new quasi-static single-phase energy recovery logic （QSSERL）, which unlike any other existing adiabatic logic family,uses a single sinusoidal supply-clock without additional timing control volta- ges. This not only ensures lower energy dissipation, but also simplifies the clock design, which would be otherwise more complicated due to the signal synchronization requirement. It is demonstrated that QSSERL circuits operate as fast as conventional two-phase energy recovery logic counterparts. Simulation with an 8bit logarithmic look- ahead adder （LLA） using static CMOS,clocked CMOS adiabatic logic （CAL,an existing typical single-phase ener- gy recovery logic）,and QSSERL,under 128 randomly generated input vectors,shows that the power consumption of the QSSERL adder is only 45% of that of the conventional static CMOS counterpart at 10MHz, and the QS- SERL adder achieves better energy efficiency than CAL when the input frequency finput is larger than 2MHz.

Preparation of ZAO film by low-temperature hydrothermal approach and its electrical property

Al-doped ZnO (ZAO) films were successfully deposited on the surface of common glasses by using low-temperature hydrothermal approach. In the reaction solution, the molar ratio of Al3+ to Zn2+ was 1∶100, the annealing temperature and time were 200 ℃ and 2-6 h, respectively. The structure of the thin films was identified by X-ray diffraction (XRD), the surface morphology and thickness of the thin films were observed by scanning electron microscopy (SEM), and the electrical performance of the thin films was measured by four-point probes. It was shown that the films with an average particle size of 27.53 nm had a preferential orientation along (002), Al3+ had replaced the position of Zn2+ in the lattice without forming the Al2O3 phase and its thickness was 20-25 μm. With the increased annealing time, the intensity of diffraction peaks was decreased, the film exhibited irregular surface morphology gradually, and the resistivity of ZAO films was increased. The lowest resistivity obtained in this study was 3.45×10-5Ω·cm.

RADIATION HAZARD AND PROTECTION OF LOW ENERGY ACCELERATORS

In this paper, the origin and type of radiation hazards as well as the main aspects of radiation protection for low-energy accelerators are discussed in general, and the problems of radiation protection and the experimental results of the operational monitoring of the five accelerators in the institute of Nuclear Science and Technology,Sichuan University, namely, one 1.2 M cyclofron, two Cockroft-waltons and two Van de Graafts, as well as a powerful electron accelerator for industrial irradiation are described. The discussion and evaluation are made according to the requirments of the National standards GB 5172-85.

Environmental Low Energy Gamma Rays Measurements in Brazilian Tropics Region During 2016

Low energy gamma radiation （0.2-10.0） MeV near the Earth＇s surface has several origins. Primary and secondary cosmic radiations with interactions of very high energy protons （〉 1 GeV） in terrestrial atmosphere are the main sources. The second most important source near the surface of the Earth and in the tropical and equatorial regions is the radon gas （Rn-222） that decays in alpha particles and gamma rays in this energy range. Also the telluric radionuclides 238U, 235U, 40K and 232Th in decays produce gamma radiation with different intensities at different locations on the surface of the Earth. Other sources less present are electrical discharges （lightning strikes） and man-made radioactive sources for medical, dental and industrial applications. In this work, it is shown that measurements of these components during all year 2016 are carried out at the ITA （Technological Institute of Aeronautics） campus in Sao Jose dos Campos, SP, Brazil and their possible correlations with atmospheric phenomena.

Differential Cross Sections of F+HD→DF+H Reaction at Collision Energies from 3.03 meV to 17.97 meV

The prototypical reaction of F+HD→DF+H was investigated at collision energies from 3.03 meV to 17.97 meV using a crossed molecular beam apparatus with multichannel Rydberg tagging time-of-flight detection.Significant contributions from both the BornOppenheimer(BO)forbidden reaction F^(*)(^(2)P_(1/2))+HD→DF+H and the BO-allowed reaction F(^(2)P_(3/2))+HD→DF+H were observed.In the backward scattering direction,the contribution from the BO-forbidden reaction F^(*)(^(2)P_(1/2))+HD was found to be considerably greater than the BO-allowed reaction F(^(2)P_(3/2))+HD,indicating the non-adiabatic effects play an important role in the dynamics of the title reaction at low collision energies.Collision-energy dependence of differential cross sections(DCSs)in the backward scattering direction was found to be monotonously decreased as the collision energy decreases,which does not support the existence of resonance states in this energy range.DCSs of both BO-allowed and BO-forbidden reactions were measured at seven collision energies from 3.03 meV to 17.97 meV.It is quite unexpected that the angular distribution gradually shifts from backward to sideway as the collision energy decreases from 17.97 meV to 3.03 meV,suggesting some unknown mechanisms may exist at low collision energies.

A 150 mV-1.2 V Fully-Integrated DC-DC Converter for Thermal Energy Harvesting

With the increasing use of low voltage portable devices and wireless systems, energy harvesting has become an attractive approach to overcome the problems associated with battery life and power source. Among the different types of microenergy scavengers, the TEG （thermoelectric generators） are one of the most commonly used one. Unfortunately, due to the very small amount of voltage delivered by the TEG, an efficient DC/DC （direct current/direct current） conversion and power management techniques are needed. In this paper, a CMOS （complementary metal oxide semiconductor） fully-integrated DC/DC convener for energy harvesting applications is presented. The startup-voltage of the converter is about 140 mV, the output voltage exceeds 1.5 V, with a 20% power efficiency at least. The architecture for boosting such extremely low voltages is based on an ultra-low-voltage oscillator cross connected to two phase charge pump. The overall circuit does not require any external components and can be fully integrated in a standard CMOS low voltage technology. A test-chip has been designed in UMC （united microelectronics corporation） 180 nm CMOS process.

An Evaluation of R134a and R245fa as the Working Fluid in an Organic Rankine Cycle Energized from a Low Temperature Geothermal Energy Source

The characteristics of an organic Rankin cycle designed to operate with a low temperature geothermal source and constant temperature cooling water supplied from freshwater ponds typical to those found near Waddan City in the Al Jufrah region of Libya were examined. Two working fluids were examined and it was concluded that the most suitable for this application was R-245fa. The off design performance of the organic Rankine cycle was examined and it was shown that the cycle is controlled by the performance of the condenser which is cooling water side temperature limited.

Artificial neural network prediction of mechanical properties of hot rolled low carbon steel strip

Conventionally, direct tensile tests are employed to measure mechanical properties of industrially pro- duced products. In mass production, the cost of sampling and labor is high, which leads to an increase of total pro- duction cost and a decrease of production efficiency. The main purpose of this paper is to develop an intelligent pro- gram based on artificial neural network （ANN） to predict the mechanical properties of a commercial grade hot rolled low carbon steel strip, SPHC. A neural network model was developed by using 7 x 5 x 1 back-propagation （BP） neural network structure to determine the multiple relationships among chemical composition, product pro- cess and mechanical properties. Industrial on-line application of the model indicated that prediction results were in good agreement with measured values. It showed that 99.2 % of the products＇ tensile strength was accurately pre- dicted within an error margin of ~ 10 %, compared to measured values. Based on the model, the effects of chemical composition and hot rolling process on mechanical properties were derived and the relative importance of each in- put parameter was evaluated by sensitivity analysis. All the results demonstrate that the developed ANN models are capable of accurate predictions under real-time industrial conditions. The developed model can be used to sub- stitute mechanical property measurement and therefore reduce cost of production. It can also be used to control and optimize mechanical properties of the investigated steel.

Apply of Low-Carbon Technology in Building Energy Conservation in Hot Summer and Cold Winter Area

Building energy conservation is the basis for carbon emission reduction, through elaborating the relationship between low carbon and energy efficient building. It points out that the construction of energy-saving emission reduction is an effective means to solve the problems of high energy consumption of the building, and it is also an important measure for China＇s carbon emission reduction. According to the climate characteristics in hot summer and cold winter area, low carbon technology suitable for the construction of energy-efficient hot summer and cold winter area is proposed which is based on the analysis of the current main building energy-saving technical measures.

Progress of entransy analysis on the air-conditioning system in buildings

It is of great importance to improve the energy performance of the air-conditioning system for building energy conversation. Entransy provides a novel perspective to investigate the losses existing in the air-conditioning system. The progress of entransy analysis in the air-conditioning system is comprehensively investigated in the present study. Firstly missions and characteris- tics of the air-conditioning system are analyzed with emphasis on heat or mass transfer process. It is found that reducing the temperature difference, i.e. reducing the entransy dissipation helps to improve the performance. Entransy dissipations and thermal resistances of typical transfer processes in the air-conditioning system are presented. Characteristics of sensible heat transfer process and coupled heat and mass transfer processes are researched in terms of entransy dissipation analysis. Reasons leading to entransy dissipation are also clarified with the help of unmatched coefficient 4. Principles for reducing the entransy dissipation and constructing a high temperature cooling system are summarized on the basis of case studies in typical handling processes. It＇s recommended that reducing mixing process, improving match properties are main approaches to reduce the entransy dissipation. The present analysis is beneficial to casting light on the essence of the air-conditioning system and proposing novel approaches for performance optimization.

Heat Transfer and Aerodynamics of Complex Shroud Leakage Flows in a Low-Pressure Turbine

A numerical investigation on over-shroud & inter-shroud leakage flow has been carried out to explore the underneath flow physics at the stage of shrouded Low Pressure(LP) turbine.Compared with the No inter-Shroud gap's Leakage flow Model(NSLM) and With inter-Shroud gap's Leakage flow Model(WSLM),the aerodynamic characteristics and the heat transfer performance have been studied.Through the aerodynamic point of view,it is concluded that due to the pressure difference between the rotor's passage and the over-shroud cavity,in the stream-wise direction,flow structure has been modified,and the inter-shroud leakage flow may even cause flow separation in the vicinity of the blade passage's throat.In the circumferential direction,separation flows appear over the rotor's shroud surface(upper platform of the shroud).Meanwhile,from the point of view of heat transfer,further provision on contour maps of the non-dimensional Nusselt number reveals that the reattachment of leakage flow would enhance the heat transfer rates and endanger the rotor's labyrinth fins over the shroud.However,due to the limited amount of inter-shroud leakage flow(current computational model),temperature distribution variation along the blade surface(near the rotor's tip section) seems to have only minor insignificant differences.At the end of the paper,the author puts forward some recommendations for the purpose of future successful turbine design.

Ausforming effects on anisotropy of mechanical properties in HSLA martensitic steel

In order to clarify effects of prior pancaked austenitic structure on microstructure and mechanical properties of transformed martensite in ausformed steel,a super-thin pancaked austenite was processed by multi-pass rolling in a 0.03-2.6Mn0.06Nb-0.01Ti(wt%) low alloy steel.The evolution of prior pancaked austenite grain during multi-pass rolling was studied using Ni-30Fe model alloy.Related with the structure and texture in the prior super-thin pancaked austenite in Ni-30Fe alloy,the texture and anisotropy of mechanical properties of transformed martensite in the studied ausformed steel were focused on.There were mainly three kinds of rolling texture components in the super-thin pancaked austenite:Goss {110} 001,copper {112} 111 and brass {110} 112.They were further transformed into the weak {001} 110 and strong {112} 110,{111} 112 texture components in the martensitic structure.The orientation relationship(OR) of lath martensite transformation from pancaked austenite in the ausformed steel deviated larger from the exact Kurdjumov-Sachs(K-S) OR than in the case of equiaxed austenite without deformation.The tensile and yield strengths of the ausformed martensitic steel first decreased and then increased as the angle between tension direction and rolling direction increased.The main reason for the anisotropy of strength was considered as the texture component {112} 110 in martensite.However,the anisotropy of impact toughness was more complex and the main reasons for it are unknown.

Effects of inclusions on microstructure and properties of heat-affected-zone for low-carbon steels

The characteristics of inclusions in two types of low-carbon steels by different deoxidization methods have been investigated by using the welding thermal simulation, the optical microscopy and scanning electron microscopy. In addition, the effects of inclusions on microstructure and properties of heat-affected-zone were studied. The nucleation and growth of intragranular acicular ferrite was observed in situ by the laser scanning confocal microscopy. The distribution of Mn element near the inclu- sion was also analyzed by the auger electron spectroscopy. The results showed that the inclusions in A1 killed steel are mainly aluminum oxides, manganese sulfide and titanium nitrides, and that the inclusions in Ti killed steel are mainly titanium oxide, manganese sulfide complex inclusion and single manganese sulfide. The auger electron spectroscopy showed that there is an Mn-depleted zone near the interface of TiOffMnS complex inclusion in the size of 1-3 gm. It could be the effective nucleus of intragranular acicular ferrite which could divide the prior austenite grains, inhibit the growth of low-temperature microstruc- ture, and refine the final microstructure, so as to improve the toughness of heat-affected-zone significantly.

Experimental Investigation on Film Cooling Performance of Pressure Side in Annular Cascades

Experimental investigations were conducted to study the film cooling performance in a low speed annular cascades using Thermochromic Liquid Crystal (TLC) technique. The test blade was placed in the second stage, where 18 blades were installed with chord length of 124.3 mm and height of 99 mm. A film hole with diameter of 4 mm, angled 28° to the tangential of the pressure surface in streamwise, was set in the middle span of the blade. The Reynolds number based on the outlet mainstream velocity and the blade chord length of the second stage varied from 1.52×105 to 2.00×105. All measurements were made with the blowing ratio varying from 0.3 to 3.0. Air and CO2 worked as coolant to achieve the coolant-to-mainstream density ratio of 1.03 and 1.57. The results show that the film coverage and cooling effectiveness scale up with the blowing ratio. Higher density ratio can generate larger film cooling coverage and effectiveness. The higher the Reynolds number, the larger the film coverage and cooling effectiveness.

Lattice instability of V_2AlC at high pressure

We investigate the elastic and thermodynamic properties of nanolaminate VzA1C by using the ab initio pseudopotential total energy method. The axial compressibility shows that the c axis is always stiffer than a axis. The elastic constants revealed the structural instability at about 500 and 732 GPa. Furthermore, elastic constants C44 reached its maximum at about 550 GPa, dif- fering with the other four C^1, G2, C13 and 6＂33 constants. The Poisson＇s ratio investigations demonstrated that a higher ionic or weaker covalent contribution in intra-atomic bonding and the degree of ionicity increases with pressure. The G/B and B]C44 investigations revealed that VzAIC is brittle and the brittleness decreases with pressure. Also, we found that V2A1C is elastic anisotropic materials and the degree of anisotropy rapidly rises with pressure. Study on Debye temperature and Grtineisen pa- rameter observed weak temperature and strong pressure responses, whereas the sensitive dependence in the thermal expansion coefficient and Helmholtz free energy are clearly seen.