压力波动吸附过程中变压时间对气相浓度的影响

本文从理论上考察了压力波动吸附过程中变压时间效应，在简单初始条件下推导了其气相浓度的数学表达式，与用正交排列法所求解值相符。此次，我们使用了线性推力模型。与此，详细考察了变压时间是否影响各种传质系数下的气相浓度研究。研究表明，时间并不影响气相中两种极端情况下，即很大或很小传质系数的浓度作用，但时间对于小的传质系数影响较大。同时还详细讨论了变压步骤情况。

Impact of remote ischemic preconditioning on wound healing in small bowel anastomoses

AIM： To investigate the influence of remote ischemic preconditioning （RIPC） on anastomotic integrity. METHODS： Sixty male Wistar rats were randomized to six groups. The control group （n = 10） had an end- to-end ileal anastomosis without RIPC. The preconditioned groups （n = 34） varied in time of ischemia and time of reperfusion. One group received the amino acid L-arginine before constructing the anastomosis （n = 9）. On postoperative day 4, the rats were re-laparotomized, and bursting pressure, hydroxyproline concentration, intra-abdominal adhesions, and a histological score concerning the mucosat ischemic injury were collected. The data are given as median （range）.RESULTS： On postoperative day 4, median bursting pressure was 124 mmHg （60-146 mmHg） in the control group. The experimental groups did not show a statistically significant difference （P 〉 0.05）. Regarding the hydroxyproline concentration, we did not find any significant variation in the experimental groups. We detected significantly less mucosal injury in the RIPC groups. Furthermore, we assessed more extensive intra-abdominal adhesions in the preconditioned groups than in the control group. CONCLUSION： RIPC directly before performing small bowel anastomosis does not affect anastomotic stability in the early period, as seen in ischemic preconditioning.

Evolution and Generation of Dynamics of Two-Mode Squeezed States of Time-Dependent Coupled Boson System

The system of the Hamiltonian involving a driving part,a single mode part,and a two-mode squeezedone and a two-mode coupled one is discussed using the Lewis-Riesenfeld invariant theory.The time evolution operatoris obtained.When the initial state is a coherent state,the quantum fluctuation of the system is calculated,and it isdependent on the squeezed part and the two-mode coupled part,but not dependent on the driving one.

Creep and tensile properties of press molding joined GMT-sheets

GMT-sheet is used in automobile bumper with high rigidity and strength, and its joining strength is influenced by lap length, one of the joined molding conditions. Fracture strength was calculated by dividing fracture load with cross-sectional area. Total five repeated measurements were made to obtain the average value. Tensile test was conducted at room temperature for 10 specimens. In addition, the effect of compression ratio on creep and tensile performance during lap joined molding was discussed. With increasing lap length, the lap joining efficiency of GMT-sheet was increased. However, higher compression ratio reduced the joining efficiency. Creep test on GMT-sheet showed abrupt fracture without tertiary creep. This can be explained by the weak thermal resistance of the resin. If GMT-sheet was exposed to high temperature for a long time, it was easily failed by external force.

Modeling heat transfer for phase transition during pressure assisted thawing treatment

The thawing time of ice and freezed Salomon fish during high pressure assisted thawing process was evaluated by computer simulation using a finite element and the results were compared with those under atmospheric pressure. The apparent specific heat method was adopted to treat the release of latent heat. The effects of different factors on the high pressure assisted thawing process were analyzed. The time reductions of different sample dimensions were estimated and the temperature contour of thawing at different conditions was obtained. The results showed that the temperature gap of phase transition was the main factor, which could shorten the thawing time. Moreover, a second order relationship was obtained between pressure and phase transition time.

Influence of specimen uniformity on mechanical behaviour of unsaturated soil

Pressure plate instrument is employed during drying, and unconfined compressive strength test is performed on the unsaturated specimen. Curves of shear force versus shear displacement, and curves of saturation degree versus time are investigated. The results show that the specimens with similar curves of saturation degree versus time have nearly identical mechanical behavior. In particular, the uniform specimens should be chosen within the lower equilibrium saturation degree because steady test results are presented. Further, the conclusion is verified by the repeated test. Thus, the method for distinguishing the uniform unsaturated specimen is obtained. In the light of the method, an improved test process is proposed. The uniform specimens should be chosen by this method under the specific matric suction, and then shear tests are carried out on the chosen unsaturated specimen. Namely, initial value of unsaturated soil is not zero matric suction but a specific suction.

Analytical investigation for stress measurement with the rheological stress recovery method in deep soft rock

Due to the difficulty and weakness of current stress measurement methods in deep soft rock, a new rheological stress recovery method of the determination of the three-dimensional(3D) stress tensor is proposed. It is supposed that rock stresses will recovery gradually with time and can be measured by embedding transducers into the borehole. In order to explore the applicability and accuracy of this method, analytical solutions are developed for stress measurement with the rheological stress recovery method in a viscoelastic surrounding rock, the rheological properties of which are depicted as both the Burger's model and a 3-parameter solid model. In such conditions, explicit analytical expressions for predicting time-dependent pressures on the transducer are derived. A parametric analysis is then adopted to investigate the influences of the grout solidification time and the mechanical properties of the grout layer. The results indicate that this method is suitable for stress measurement in deep soft rock, the characteristics of which are soft, fractured and subjected to high geo-stress.

An elastic-viscous-plastic model for overconsolidated clays

The influences of time on clays are discussed first,and the concept of the instant normal compression line is proposed by analyzing the existing theories and experimental results.Based on the creep law,the relationship between the aging time and the overconsolidation parameter is built.With the reloading equation of the UH model(unified hardening model for overconsolidated clays) used to calculate the instant compression deformation,a one-dimensional stress-strain-time relationship is proposed.Furthermore,the evolution of this relationship is analyzed,and the characteristic rate that is a function of the overconsolidation parameter is defined.Then a three-dimensional elastic-viscous-plastic constitutive model is suggested by incorporating equivalent time into the current yield function of the UH model.The new model can describe not only creep,rate effect and other viscous phenomena,but also shear dilatancy,strain softening and other behaviors of overconsolidated clays.Besides,compared with the modified Cam-clay model it requires only one additional parameter(the coefficient of secondary compression) to consider the creep law.Finally,because the proposed model can be changed into the UH model under instantaneous loading,the elastic-plastic and elastic-viscous-plastic frameworks are unified.

Variational Formulation of 1-D Unsteady Compressible Flow in a Deforming Tube

The variational principles for 1-D unsteady compressible flow in a deforming tube derived in a previous paper are improved essentially by reconstructing the initial/final-integral terms according to a new method suggested in a recent paper. As a result, the inherent shortcoming of variational principles of being unable to admit physically rational initial/final-value conditions in initial/boundary-value problems is successfully eliminated. Thus, a new theoretical basis for the time-space finite-element analysis is provided.

Panda X-III： Searching for neutrinoless double beta decay with high pressure ^(136)Xe gas time projection chambers

Searching for the neutrinoless double beta decay(NLDBD)is now regarded as the topmost promising technique to explore the nature of neutrinos after the discovery of neutrino masses in oscillation experiments.Panda X-III(particle and astrophysical xenon experiment III)will search for the NLDBD of136Xe at the China Jin Ping Underground Laboratory(CJPL).In the first phase of the experiment,a high pressure gas Time Projection Chamber(TPC)will contain 200 kg,90%136Xe enriched gas operated at10 bar.Fine pitch micro-pattern gas detector(Microbulk Micromegas)will be used at both ends of the TPC for the charge readout with a cathode in the middle.Charge signals can be used to reconstruct the electron tracks of the NLDBD events and provide good energy and spatial resolution.The detector will be immersed in a large water tank to ensure～5 m of water shielding in all directions.The second phase,a ton-scale experiment,will consist of five TPCs in the same water tank,with improved energy resolution and better control over backgrounds.

Variations of shear wave splitting in the 2013 Lushan Ms7.0 earthquake region

In this paper, variations of shear wave splitting in the 2013 Lushan Ms7.0 earthquake sequence were studied. By analyzing shear wave particle motion of local events in the shear wave window, the fast polarization directions and the delay time between fast and slow shear waves were derived from seismic recordings at eight stations on the southern segment of the Longmenshan fault zone. In the study region, the fast polarization directions show partition characteristics from south to north. And the systematic changes of the time delays between two split shear waves were also observed. As for spatial distribution, the NE fast polarization directions are consistent with the Longmenshan fault strike in the south of focal region, whereas the NW fast direction is parallel to the direction of regional principal compressive stress in the north of focal region. Stations BAX and TQU are respectively located on the Central and Front-range faults, and because of the direct influence of these faults, the fast directions at both stations show particularity. In time domain, after the main shock, the delay times at stations increased rapidly, and decreased after a period of time. Shear-wave splitting was caused mostly by stress-aligned microcracks in rock below the stations. The results demonstrate changes of local stress field during the main shock and the aftershocks. The stress on the Lushan Ms7.0 earthquake region increased after the main shock, with the stress release caused by the aftershocks and the stress reduced in the late stage.