《透气孔》中人物的生存困境

《透气孔》是作家马卡宁创作于20世纪80年代的中篇小说。马卡作为现实主义作家的代表人物,在这部小说创作中聚焦于前苏联战后重建结束后的社会现实状况,着力描绘人们在“安乐化”过程当中的身心变化历程。本文从“生存困境”“伦理关系困境”“精神困境”三个方面对于小说中的主要人物所处的现实困境进行了分析,同时对于作品的当代社会意义进行了进一步的思考。

Mathematical Model of Gas Permeation Through PTFE Porous Membrane and the Effect of Membrane Pore Structure

Membrane-based separation processes are new technology combined membrane separation with conventional separation. Hydrophobic porous membranes are often used in these processes. The structure of hydrophobic porous membrane has significant effect on mass transfer process. The permeabilities of five kinds of gas, He, N2, O2, CO2 and water vapor, across six polytetrafluoroethylene(PTFE) flat membranes were tested experimentally. Results indicated that the greater the membrane mean pore size and the wider the pore size distribution are, the higher the gas permeability. A gas permeation model, including the effects of membrane structure parameter and gas properties, was established. A comprehensive characteristic parameter (including porosity, thickness and tortuosity) was found more effective to express the influence of membrane structure in gas permeation process. The predicted permeation coefficients were in good agreement with experimental data.

Gas separation using sol–gel derived microporous zirconia membranes with high hydrothermal stability

A microporous zirconia membrane with hydrogen permeance about 5 × 10-8mol·m-2·s-1·Pa-1, H2/CO2 permselectivity of ca. 14, and excellent hydrothermal stability under steam pressure of 100 k Pa was fabricated via polymeric sol–gel process. The effect of calcination temperature on single gas permeance of sol–gel derived zirconia membranes was investigated. Zirconia membranes calcined at 350 °C and 400 °C showed similar single gas permeance, with permselectivities of hydrogen towards other gases, such as oxygen, nitrogen, methane, and sulfur hexa fluoride, around Knudsen values. A much lower CO2permeance（3.7 × 10-9mol·m-2·s-1·Pa-1）was observed due to the interaction between CO2 molecules and pore wall of membrane. Higher calcination temperature, 500 °C, led to the formation of mesoporous structure and, hence, the membrane lost its molecular sieving property towards hydrogen and carbon dioxide. The stability of zirconia membrane in the presence of hot steam was also investigated. Exposed to 100 k Pa steam for 400 h, the membrane performance kept unchanged in comparison with freshly prepared one, with hydrogen and carbon dioxide permeances of 4.7 × 10-8and ~ 3 × 10-9mol·m-2·s-1·Pa-1, respectively. Both H2 and CO2permeances of the zirconia membrane decreased with exposure time to 100 k Pa steam. With a total exposure time of 1250 h, the membrane presented hydrogen permeance of 2.4 × 10-8mol·m-2·s-1·Pa-1and H2/CO2 permselectivity of 28, indicating that the membrane retains its microporous structure.

Analysis of mine's air leakage based on pressure gradient matrix between nodes

Air leakage may significantly affect the effectiveness of mine ventilation by in- creasing the cost of ventilation and arousing problems for ventilation management.Fur- thermore,air leakage may accelerate the process of coal spontaneous combustion and cause gas explosion,thus greatly threatens the safety of coal production.The estimation of air leakage,therefore,have great practical significance.For any ventilation system of coal mines,there is a defined pattern of pressure gradient which drived the mine air to flow in the network,drives possible air leakage to go shortcut as well.Air leakage may occur through ventilation structures such as ventilation doors and fractures of the surroun- dig coal and rock of airways.A concept and the relevent calculation method of the pres- sure gradient matrix was put forward to assist the analysis of potential air leakage routes. A simplified example was used to introduce the application principle of'pressure gradient matrix in identifying all the potential air leaking routes,which offers a deeper understand- ing over the ventilation system and the prevention of coal spontaneous combustion.

Effects of High Temperature Stress on Microscopic and Ultrastructural Characteristics of Mesophyll Cells in Flag Leaves of Rice

The microscopic and ultrastructural characteristics of mesophyll cells in flag leaves of two rice lines （a thermosensitive line 4628 and a thermo-resistant line 996） under high temperature stress （37℃ during 8：00-17：00 and 30℃ during 17：00-8：00） were investigated using an optical and a transmission electron microscopy. The membrane permeability and malondialdehyde content increased under the high temperature stress, and the increase of both variables was greater in the line 4628 than in the line 996. Under the high temperature stress, the line 996 showed tightly arranged mesophyll cells in flag leaves, fully developed vascular bundles and some closed stomata, whereas the line 4628 suffered from injury because of undeveloped vascular bundles, loosely arranged mesophyll cells and opened stomata. The mesophyll cells in flag leaves of the line 4628 were severely damaged under the high temperature stress, i.e. the chloroplast envelope became blurred, the grana thylakoid layer was arranged loosely and irregularly, the stroma layer disappeared, many osmiophilic granules appeared within the chloroplast, the outer membrane of mitochondria and the nucleus disintegrated and became blurred, the nucleolus disappeared, and much fibrillar-granular materials appeared within the nucleus. In contrast, the mesophyll cells in flag leaves of the line 996 maintained an intact ultrastructure under the high temperature stress. From these results, it is suggested that the ultrastructural modification of the cell membrane system is the primary plant response to high temperature stress and can be used as an index to evaluate the crop heat tolerance.

Air Filter Simulation by Geodict

In this paper, we discussed the relationship of filter effictency and pressure drop with the porosity, fiber diameter and filter thickness by Oeodict. We found that filter efficiency will increase when filter porosity and fiber diameter decreasing or filter thickness increasing. And the pressure drop has a linear relationship with filter thickness and non-linear relationship with filter porosity and fiber diameter. We also compared the simulation results with the real test results by TSI 3160. Although there are some differences, I think Ocodict can be used to predict filter effictency and pressure drop.

Pore-scale simulation of gas-water flow in low permeability gas reservoirs

A novel method was developed to establish a realistic three dimensional(3D) network model representing pore space in low permeability sandstone.Digital core of rock sample was established by the combination of micro-CT scanning and image processing,then 3D pore-throat network model was extracted from the digital core through analyzing pore space topology,calculating pore-throat parameters and simplifying the shapes of pores and throats.The good agreements between predicted and measured porosity and absolute permeability verified the validity of this new network model.Gas-water flow mechanism was studied by using pore-scale simulations,and the influence of pore structure parameters,including coordination number,aspect ratio and shape factor,on gas-water flow,was investigated.The present simulation results show that with the increment of coordination number,gas flow ability in network improves and the effect of invading water on blocking gas flow weakens.The smaller the aspect ratio is,the stronger the anisotropy of the network is,resulting in the increase of seepage resistance.It is found that the shape factor mainly affects the end points in relative permeability curves,and for a highly irregular pore or throat with a small shape factor,the irreducible water saturation(Swi) and residual gas saturation(Sgr) are relatively high.

21世纪的文学是形象和思维的体系——马卡宁访谈录

作者前言:2002年9月至2003年8月,笔者在俄罗斯走访了许多活跃在今日文坛上的著名作家。与他们的相约相识,长谈短晤,使我触摸到了当代俄罗斯文学发展的脉搏。早在出国前,我就拟定了一份准备拜访的作家名单。这个名单是按照老中青结合、爱国派与自由派兼顾、包含现实主义和后现代主义作家的原则制定的。现在看来,这个计划基本上都实现了。我想这得益于两个方面:一是俄罗斯人性格比较外向,热情好客,乐于介绍自己和了解别人;二是俄罗斯人对中国怀有一种特殊的感情,对中国现况也非常感兴趣。在我所走访的近十位作家中,佩列文和索罗金都曾自费到中国旅游;乌利茨卡娅坦言,她近来已很少接见来访者,因为我是从中国来的,她才愿意相见;而马卡宁更是向我历数他年轻时同中国人交往的点点滴滴,怀念之情溢于言表。在我实现采访计划的整个过程中,他都给了我最真诚的鼓励和最切实的帮助。这些作家以各具特色的形象气质、言谈风度走入我的视野,在我面前展开了他们丰富多彩的人生经历和生活状态。一如小说中的人物,令我难以释怀。与他们的亲切交往——地铁或广场的相会,酒吧或家中的详谈,河边或街头的漫步,时常萦绕在我的记忆中。在此,我愿意把这些仍然带着新鲜色彩的谈话记述下来,与读者分享这次独特的文学之旅。

High and selective capture of low-concentration CO2 with an anion-functionalized ultramicroporous metal-organic framework

CO2 capture,especially under low-pressure range,is of significance to maintain long-duration human operation in confined spaces and decrease the CO2 corrosion and freezing effect for the liquefaction of natural gas.Herein,we for the first time report a novel anion-functionalized ZU-16-Co(TIFSIX-3-Co,TIFSIX=hexafluorotitanate(TiF62−),3=pyrazine),which exhibits one-dimensional pore channels decorated by abundant F atoms,for efficient CO2 capture at a concentration around 400–10,000 ppm.Among its isostructural MFSIX-3(M=Si,Ti,Ge)family materials,ZU-16-Co with fine-tuned pore size of 3.62Åexhibits the highest CO2 uptake at 0.01 bar(10,000 ppm)and 1 bar(2.63 and 2.87 mmol g−,respectively).The high CO2 capture ability of ZU-16-Co originates from the fine-tuned pore dimensions with strong F⋯C=O host-guest interactions and relatively large pore volumes coming from its longer coordinated Ti-F-Co distance(3.9Å)in c direction.The excellent carbon trapping performance was further verified by dynamic breakthrough tests for CO2/N2(1/99 and 15/85)and CO2/CH4(50/50)mixtures.The adsorption and separation performances,resulting from the fine-tuned pore system with periodic arrays of exposed functionalities,demonstrate that ultramicroporous ZU-16-Co can be a promising adsorbent for low-concentration carbon capture.