加气灌溉对温室番茄生长、产量及品质的影响

本试验目地是探明加气灌溉不同灌水量和加气灌水频率对温室番茄生长、产量和品质的影响,为实际生产应用奠定基础。采用温室小区对照试验,设置3个不同作物-皿系数Kcp(Kcp=0.8、Kcp=1.0、Kcp=1.2)和2个加气灌水频率(1次/3d、1次/6d)共组成6个处理,均以对应的不加气灌溉为对照,比较不同处理对番茄植株生长及果实产量和品质的影响。结果表明,在相同的灌溉频率及灌水量下,加气灌溉可以提高番茄的生长量、产量及品质,加气灌溉的番茄株高较不加气灌溉增加1.44%、茎粗增加3.02%、产量增加19.49%;加气灌溉有利于温室番茄茎粗、株高的生长,并且对番茄的产量和品质均有利。加气灌溉处理时,在相同的灌水量条件下,1次/6d较1次/3d的加气灌水频率,株高增加了8.08%,茎粗增加了6.33%,产量增加了26.01%。由此得出:加气灌溉对植株生长量及果实产量和品质的影响明显优于不加气处理;灌水频率为1次/6d且Kcp=1.0的处理最有利于番茄生长量的积累、产量的提高和品质的改善。

PREPATATION OF SPODUMENE-DERIVED LOW EXPANSION COEFFICIENT GLASS CERAMIC IN THE SYSTEM Li_2O-Al_2O_3-SiO_2

In this paper ,spodumene mineral was used as raw material for fabricating glass ceramic with the addition of MgO,ZnO and TiO2,ZrO2. The expansion coefficient of the materials is 5. 5×107/℃ . Also the effects of the heat treatment on the crystallzing behaviour has been discussed by XRD and DTA.

Self-excited vibration of driveline for vehicle launch

The launch shudder phenomenon induced by self-excited vibration of driveline was stud- ied with a compact car equipped with AMT as research object. The research showed that self-excited vibration was closely related with damping of driveline, the variation of friction coefficient, equiva- lent radius of friction plate and applied force of pressure plate. Six DOFs torsional vibration model of vehicle driveline was established according to the parameters of the certain compact car. The simula- tion was carried out and the result was compared with test data. It was found that the negative slope of friction coefficient with relative slip speed does not necessarily lead to self-excited vibration and the frequency of self-excited vibration on 1st gear is near to the 1st order of torsional natural frequen- cy. The influence of each viscous damping in driveline on self-excited vibration was analyzed by sim- ulation and the results showed that increasing the torsional dampings of half-axles and tires properly was effective to improve launch shudder phenomenon.

Phenol Oxidation by Combined Cavitation Water Jet and Hydrogen Peroxide

The paper presents results of phenol oxidized under the conditions of high temperature created during collapse of cavitation bubbles.The degradation efficiency has been greatly improved by using cavitation water jets combined with H2O2 as demonstrated in laboratory tests.Various factors affecting phenol removal ratio were ex-amined and the degradation mechanism was revealed by high performance liquid chromatography(HPLC).The re-sults showed that 99.85% of phenol was mineralized when phenol concentration was 100 mg·L-1 with pH value of 3.0,H2O2 concentration of 300 mg·L-1,confining pressure of 0.5 MPa,and pumping pressure of 20 MPa.The in-termediate products after phenol oxidation were composed of catechol,hydroquinone and p-benzoquinone.Finally,phenol was degraded into maleic acid and acetic acid.Furthermore,a dynamic model of phenol oxidation via cavi-tation water jets combined with H2O2 has been developed.

Slide stability of hydraulic structures on subbed soil

The study on slide stability of hydraulic structures on subbed soil was made. Using the slide test results of dragged concreting base plates on subbed soil pits, the decreased value of bearing capacity on slide after re- bound and repression influence of subbed soil was determined, and the envelope of ultimate slide shear resistance was also quantitatively determined. Due to the lack of similar mechanisms of slide stability on subbed soil and base plate of hydraulic structures, different safety coefficients for the slide stability were adopted. It was suggested to use the maximum compressive stress O＇m~ of eccentric load to predict structure displacement, slide and creepy slippage of subbed soil, to determine the sliding creepy contour and limit the maximum load on subbed soil. Two hydraulic structures that had been put into operation were reviewed by this method, and the results accorded with the real conditions.

Experimental research on thermal transport properties of crystallized palladium-based alloys

Palladium-based alloy is a kind of material with a high glass forming ability and can be easily formed into an amorphous state. After an annealing process, it can also be maintained at a crystallized state. To study the thermal and electrical transport properties of crystallized palladium-based alloys, the steady-state T-type method, standard four-probe method, and AC heating-DC detecting T-type method were used to measure the thermal conductivity, electrical conductivity, and Seebeck coeffi- cient of crystallized Pd4oNiloCu3oP2o and Pd43Nilo- Cu27P2o alloys respectively. The results show that compared to amorphous samples, the thermal conductivity and electrical conductivity of crystallized palladium-based alloys are significantly higher, while the Seebeck coeffi- cient is lower. The ratio of crystallized and amorphous thermal conductivity is higher for Pd43Ni10Cu27P2o alloy fiber which has a higher glass forming ability, while the ratio of electronic thermal conductivity almost remains constant for both alloy fibers. The results also show that the slope of electrical resistivity to temperature is a function of elemental composition for crystallized quaternary palla- dium-based alloy fibers. The sensitivity of thermal conductivity and electrical conductivity to the composition is high, while the correlation between Seebeck coefficient and composition is relatively weak.

Electrical properties and thermal sensitivity of Ti/Y modified CuO-based ceramic thermistors

The Ti/Y modified CuO-based negative temperature coefficient （NTC） thermistors, Cu0.988-2yY0.008TiyO （TYCO; y-- 0.01, 0.015, 0.03, 0.05 and 0.07）, were synthesized through a wet-chemical method followed by a traditional ceramic sintering technology. The related phase component and electrical properties were investigated. XRD results show that the TYCO ceramics have a monoclinic structure as that of CuO crystal. The TYCO ceramics can be obtained at the sintering temperature 970℃-990℃, and display the typical NTC characteristic. The NTC thermal-sensitive constants of TYCO thermistors can be adjusted from 1112 to 3700 K by changing the amount of Ti in the TYCO ceramics. The analysis of complex impedance spectra revealed that both the bulk effect and grain boundary effect contribute to the electrical behavior and the NTC effect. Both the band conduction and electron-hopping models are proposed for the conduction mechanisms in the TYCO thermistors.

An improved cooperative spectrum detection algorithm for cognitive radio

The ability to detect the primary user＇s signal is one of the main performances for cognitive radio networks. Based on the multi-different-cyclic-frequency character- istics of the cyclostationary primary user＇s signal and the cooperation detection advantage of the multi-secondary-user, the paper presents the weighted cooperative spectrum detection algorithm based on cyclostationarity in detail. The core of the algorithm is to detect the primary user＇s signal by the secondary users＇ cooperation detection to the multi-different-cyclic-frequency, and to make a final decision according to the fusion data of the independent secondary users＇ detection results. Meanwhile, in order to improve the detection performance, the paper proposes a method to optimize the weight on basis of the deflection coefficient criterion. The result of simulation shows that the proposed algorithm has better performance even in low signal-to-noise ratio （SNR）.

A microextraction approach for rapid extraction and separation of Mn(Ⅱ) and Co(Ⅱ) using saponified D2EHPA system

In this paper,we proposed a microextraction approach for the extraction and separation of Mn(Ⅱ)and Co(Ⅱ)from sulfate solution simulating leachate of spent lithium-ion battery cathode materials using saponified di-(2-ethylhexyl)phosphoric acid system.The effects of the following operational variables were investigated:equilibrium pH,tri-«-butyl phosphate concentration,saponification rate,two-phase ratio and residence time.The results showcased that the microextractor can reach the extraction equilibrium within 20 s,thereby greatly reducing necessary extraction time comparing to that of conventional processes.The volumetric mass transfer coefficient showed 8-21 times larger than that of batch device.With the help of microextractor,95%of Mn(Ⅱ)was extracted with a single theoretical stage at a chosen two-phase ratio of 3:1,and the separation factor β_(Mn/Co) was as large as 65.5.In the subsequent stripping step,more than 99%of manganese from loaded phase was easily stripped under optimal conditions.The microextraction approach greatly enhances the mass transfer while enabling a continuous and controllable extraction process within a simple structure design.When extracting spent electrode material with microextractors,the comprehensive recovery of mangenese can reach 96%.The microextraction approach has a good applicability in the spent lithium-ion battery cathode materials recycling at both bench and industrial scales.

A Bilinear Immersed Finite Volume Element Method for the Diffusion Equation with Discontinuous Coefficient

This paper is to present a finite volume element(FVE)method based on the bilinear immersed finite element(IFE)for solving the boundary value problems of the diffusion equation with a discontinuous coefficient(interface problem).This method possesses the usual FVE method’s local conservation property and can use a structured mesh or even the Cartesian mesh to solve a boundary value problem whose coefficient has discontinuity along piecewise smooth nontrivial curves.Numerical examples are provided to demonstrate features of this method.In particular,this method can produce a numerical solution to an interface problem with the usual O(h2)(in L2 norm)and O(h)(in H1 norm)convergence rates.