非知青化:知青小说家族中的变异与分离——知青文学近年发展趋势探讨之二

作为新时期小说发轫阶段重要一翼的知青小说(所谓知青文学无疑主要指知青小说,或者说它主要靠小说这种样式来支撑),曾有过一段较为萧条的光阴,但近两三年来明显呈现出东山再起的复兴状态。

石头河灌区青化万亩节水示范园管理与运行存在的问题及对策

文中结合青化万亩节水示范园运行与管理工作之实际,深入地分析了存在的主要问题,提出了解决这些问题的措施和建议,对今后节水示范园区各项工程设施的完善与节水灌溉技术的进一步推广具有一定的参考价值。

A review of the catalytic preparation of mesophase pitch

Because of its high purity and excellent orientation, mesophase pitch is a superior precursor for high-performance car-bon materials. However, the preparation of top-notch mesophase pitch faces challenges. Catalytic polycondensation at low temperat-ures is more favorable for synthesizing mesophase pitch, because it circumvents the high-temperature free radical reaction of other thermal polycondensation approaches. The reaction is gentle and can be easily controlled. It has the potential to significantly im-prove the yield of mesophase pitch and easily introduce naphthenic characteristics into the molecules, catalytic polycondensation is therefore a preferred method of synthesizing highly spinnable mesophase pitch. This review provides a synopsis of the selective pre-treatment of the raw materials to prepare different mesophase pitches, and explains the reaction mechanism and associated research advances for different catalytic systems in recent years. Finally, how to manufacture high-quality mesophase pitch by using a cata-lyst-promoter system is summarized and proposed, which may provide a theoretical basis for the future design of high-quality pitch molecules.

Projected changes in extreme snowfall events over the Tibetan Plateau based on a set of RCM simulations

Extreme snowfall events over the Tibetan Plateau(TP)cause considerable damage to local society and natural ecosystems.In this study,the authors investigate the projected changes in such events over the TP and its surrounding areas based on an ensemble of a set of 21st century climate change projections using a regional climate model,RegCM4.The model is driven by five CMIP5 global climate models at a grid spacing of 25 km,under the RCP4.5 and RCP8.5 pathways.Four modified ETCCDI extreme indices-namely,SNOWTOT,S1mm,S10mm,and Sx5day-are employed to characterize the extreme snowfall events.RegCM4 generally reproduces the spatial distribution of the indices over the region,although with a tendency of overestimation.For the projected changes,a general decrease in SNOWTOT is found over most of the TP,with greater magnitude and better cross-simulation agreement over the eastern part.All the simulations project an overall decrease in S1mm,ranging from a 25%decrease in the west and to a 50%decrease in the east of the TP.Both S10mm and Sx5day are projected to decrease over the eastern part and increase over the central and western parts of the TP.Notably,S10mm shows a marked increase(more than double)with high cross-simulation agreement over the central TP.Significant increases in all four indices are found over the Tarim and Qaidam basins,and northwestern China north of the TP.The projected changes show topographic dependence over the TP in the latitudinal direction,and tend to decrease/increase in low-/high-altitude areas.

50万吨原油保卫战——延长油矿管理局青化砭油矿2004年原油稳产大战纪实

引子 2003年,延长油矿管理局青化砭油矿创造了特低渗油田原油年增产量27万吨,实现了年产50万吨的辉煌业绩。这一神来之笔的神奇之处在于:在上世纪60、80、90年代,延长油矿原油勘探队,曾经在延安市宝塔区冯庄、梁村、青化砭三乡镇的部分区域三进三出进行勘查,但每一次的物化碳研究结果都无一例外地将该地区列为3-4类区,宣告这里无可开采原油。然而,时隔多年以后。

50万吨:谱写跨越式发展新篇章——延长油矿管理局青化砭油矿2003年原油产量突破50万吨记

一个激荡人心的消息响彻整个陕北高原:延长油矿管理局青化砭油矿在2003年岁尾,原油产量一举突破50万吨大关。在去年产量23万吨的基础上,实现大跨越,开创了该矿的历史新纪元! 50万吨,穿越时空的世纪之光。

奇迹,诞生在山坳里——来自延长油矿管理局青化砭油矿的报告

从延安驱车沿210国道东行,过姚店,北行20里便到中国解放战争史上著名的"青化砭战役"的所在地——青化砭小镇。半个多世纪前,党中央、毛主席转战陕北时,曾在这里打响了"三战三捷"的第一仗——青化砭战役。从此,这个默默无闻的小镇名扬天下,载入中国革命战争的史册。弹指一挥间,旧貌变新颜。如今。

Global CO_(2) concentration change induced by“trigger-connectors”model,especially since about 24 Ma?A preliminary hypothesis

Background,aim,and scope The tectonic uplift of the Cenozoic Tibetan Plateau has produced a chain effect,which is an excellent location for Earth system science research,and its uplift process,mechanism and environmental effects are the hot spot and frontier of the current research.The“Tibetan Plateau uplift-weathering-CO_(2) concentration-global climate change”model was put forward by Raymo and Ruddiman to interpret the Late Cenozoic climate change.However,there are still some questions suspended,such as does the weathering of the Tibetan Plateau have the ability to control the global climate?How to explain the modern-like global CO_(2) concentration starting at about 24 Ma?Here,a short space was taken to present a brainstorm about the above questions on account of existing geological pieces of evidence.Materials and methods In this paper,we integrate the formation and evolution of the Yangtze River and Pearl River,the origin and development of the Asian inland aridification-monsoon system,the Cenozoic tectonic uplift process of the Tibetan Plateau,and the westerly winds to discuss and analyze the relationship between the Cenozoic CO_(2) concentration changes and the uplift of the Tibetan Plateau and why the CO_(2) concentration similar to the present was formed at about 24 Ma.Results Similar correspondence of the surface uplift history of Xizang,other global mountains,and the declining CO_(2) concentration could support the theory Tibetan Plateau weathering inf luences CO_(2) concentration.Starting from 24 Ma,the most important character was the uplift and erosion of Xizang and Himalaya,collaborating with Ocean Iron Fertilization(OIF)together as an entity to control the atmospheric CO_(2) concentration because the great Asian rivers,Asian monsoons,and westerlies connected Xizang and surrounded seas together through materials transportation.Discussion Paleogeographic reconstructions from 40 Ma to 20 Ma illustrate that the main topographic change occurred in the Andes,Cordillera orogenic belt,and Xizang.We comprise a comprehensive set of evidence from independent data,which correspond temporally with the tipping point(about 24 Ma)of the atmospheric CO_(2) and we noticed that modern-like Asia monsoon,inland aridity,Asian great rivers,and climate zone formed at about 24 Ma and also there are tectonic activities for the Andes and Rockies.We raised the possibility that the modern-like atmospheric CO_(2) concentration at about 24 Ma was caused by the above geological factors.Here the rivers,monsoon,and westerlies are termed as“connectors”.In addition,these Asian rivers originated from Xizang,the monsoon,and inner Asian aridification are strongly a function of the uplift and growth of Xizang,thus,Xizang here is named as“trigger”.The distinct character of“trigger-connectors”model is that this not only takes the monsoon,westerlies,and the global great rivers into consideration but also expands the range which inf luences atmospheric CO_(2) concentration,from local points to a vast area since about 24 Ma,such as from Tibetan Plateau to Asia,including surrounded seas,after about 24 Ma.However,because the opening of the Late Oligocene-Early Miocene Antarctic periphery straits is highly coincident with the onset of modern-like global atmospheric CO_(2) concentration,we are forced to consider that they also had a significant impact on the reduction of atmospheric CO_(2) concentrations at this time.Conclusions“Trigger-connectors”was put forward to explain the Cenozoic CO_(2) variation,especially modern-like global CO_(2) concentration since about 24 Ma.Recommendations and perspectives Here we use the“trigger-connectors”model to explain the formation of modern-like CO_(2) concentrations starting at about 24 Ma,but there are still some problems.The most important premise for the“trigger-connectors”model is the constructed Cenozoic CO_(2) concentration record is reliable,which is the foundation of our hypothesis.In the future,potential improvements should focus on topographic reconstructions of Xizang and the global mountains.Here we have concentrated on Xizang in the considered timeslices but still,pay less attention to other global orogenic belts.Collaborations with geologist experts in those regions could provide valuable feedback to evaluate their potential role of them in CO_(2) evolution.What is more,considerable progress may be achieved with the addition and consideration of more and new geological data.

Experimental study of water aging on asphalt during service life of pavements

In order to further simulate the real condition of pavements during the service life,moisture is considered in long-term aging tests based on the existing researches about thermal aging and oxidation aging of asphalt.Water is injected into the pressure aging vessel（PAV）to simulate the aging process during the service life.The performance-based strategic highway research program（SHRP）parameters G/sinδ and S（t）are adopted to evaluate the high-temperature properties and low-temperature properties of the aged asphalt,respectively.The Thailand 90# asphalt,the modified Thailand 90# asphalt and the Shell 70# asphalt are used in the test.It is found that the moisture has a significant influence on parameter G/sinδ when combined with heat and oxygen,so water aging makes high-temperature performance decay more seriously.But the low-temperature performance does not change remarkably after water aging.Since the influences of temperature,oxygen and water are taken into account in the PAV test,the accuracy of asphalt aging tests can be improved and the long-term aging process of asphalt pavement can be exactly simulated.

Impacts and Countermeasures of Climate Change on Animal Husbandry in Qinghai Plateau and Its Surrounding Area

The paper aims to study the impacts and countermeasures of climate change on animal husbandry in Qinghai plateau and its surrounding area,and evaluate the effect of countermeasures.Results showed that：First,the annual mean temperature,annual mean maximum temperature and annual mean minimum temperature showed an increasing trend in Qinghai plateau during the time from 1961 to 2008; the annual precipitation had not obvious change,but the obvious feature of seasonal change; wind speed and sunshine hours showed a decreasing trend during the time from 1961 to 2008.Secondly,under the current climate condition,grassland productivity showed a decreasing trend,and the grassland theoretical capacity affected by grassland productivity decreased too; warm winter was in favor of livestock overwintering safely,which resulted in a high level of the survival rate of young stock; temperature increasing and precipitation decreasing were beneficial to the fatness of livestock,but the meat yield of livestock was affected by some negative factors such as grassland degradation; livestock diseases had a close relationship with weather condition,and adverse weather condition may arose many diseases of livestock.Thirdly,in view of the current problems of livestock production,we took a series of countermeasures including grass industry construction,livestock improvement,developing new modes of animal husbandry,control and prevention of stockbreeding diseases and insect pests and recovery of meteorological disasters,which played a important role in promoting grassland productivity,solving the problem of the imbalances between livestock and forage,protecting the ecological environment and improving livestock performance.

Seasonal Changes in Photosynthetic Characteristics of Ammopiptanthus mongolicus

Seasonal changes in the photosynthetic characteristics of Ammopiptantus mongolicus (Maxim. )Chen f. were studied. When the net photosynthetic rate decreased with the elevation of air temperature, thestomatal conductance and stomatal limitation value tended to decline simultaneously, while the interoellularCO2 concentration was increased. According to the two criteria discriminating the stomatal limitation of Photosynthesis suggeSted by Fmrquhar and Sharkey, the seasonal changes in these parameters indicated that the decrease in Pn may not be due to stomatal factor. These studies proved that the relative contents of the large subunit of Rubisco and the photochemical activities correlated with the seasonal changes in the net photosyntheticrate, whieh may show that these two factors contribute primarily to the seasonal changeS in CO2 assimilation.

Extraction Characteristics of Anthocyanins from Preliminarily-processed Products of Purple Sweet Potatoes during the Gelatinization Process

Objective] This study aimed to investigate the method for efficient utilization and development of purple sweet potatoes. [Method] Purple sweet potatoes were dried at two specific temperatures and prepared into preliminarily-processed products for gelatinization simulation to analyze the extraction amount of anthocyanins from gelatinized samples at different gelatinization stages. [Result] During the gelatinization process, the extraction rate of anthocyanins from purple sweet potato samples reached the highest as the temperature rised from 90 ℃ to 95 ℃,and the extraction amount of anthocyanins reached the maximum at 15 min postheat preservation at 95 ℃. Purple sweet potato samples dried at 60 ℃ exhibited larger retention amount, larger maximum extraction amount and higher maximum extraction rate of anthocyanins compared with those dried at 110 ℃. [Conclusion] Drying at low temperatures and appropriately shortening the initial gelatinization stage below 90 ℃ is conducive to the retention and extraction of anthocyanins from purple sweet potatoes.

Effect of Irrigation on Groundwater Dynamic Change in the Typical Irrigated Area of Qinghai Province

Under the influence of the natural and human factors, water table of irri- gated area Changes frequently, but it is mainly affected by irrigation water infiltration replenishment during the irrigation. 5 groundwater observation wells were constructed in experimental plot of the Daxia irrigated area to carry out the experiment of the effect of irrigation on groundwater dynamic change in this research. The results showed that the groundwater stage dynarnic change rule of spring and seedling irri- gation stage in the typical plot was fit to the hydrological geology condition of grade- I terrace of Huangshui river valley. On the whole, lateral canal water direction formed a line effect. The No. 1 and No. 2 observation well were the closest to the lateral canal, which received more supplies, and the water level was the highest; the No, 3 observation well took the second place; The No. 4 and No. 5 observation well accepted least supplies, and the water level was the lowest. The rangeability of water table of spring irrigation period was significantly higher than that of seedling irrigation period, this is mainly due to the difference value of intake water volume and drainage water volume of spring irrigation phase was significantly higher than the seedling irrigation phase.

In situ synthesized Cu-ZSM-5/cordierite for reduction of NO

ZSM-5 zeolites were directly synthesized on the surface of honeycomb cordierite substrates by hydrothermal method and certified by XRD and SEM techniques; the adhesion of ZSM-5 coatings was evaluated by ultrasonic vibration. Cu-ZSM-5/cordierite monolithic catalyst was prepared by ion-exchange and impregnation method and applied for the selective catalytic reduction （SCR） of NO by NH3 using a simulated diesel exhaust. The results show that the cordierite surface is almost completely covered by ZSM-5 crystals and the crystallization time greatly impacts the loadings and adhesion of ZSM-5 coatings on substrate, the NOx removal rate over Cu-ZSM-5/cordierite is above 90% in a temperature range of 240-480℃. Moreover, Cu-ZSM-5/cordierite prepared by different methods shows a wide temperature window （240-540 ℃） with high NO removal activities.

Performance evaluation and chemical property analysis of RWMA binders with 100% artificial reclaimed asphalt

The performance evaluation and chemical property analysis of the recycled warm mix asphalt （RWMA） binders containing 100% artificial reclaimed asphalt （ RA） are presented, and the combined effects of different percentages of the rejuvenator and warm mix additive （WMA） additives on RWMA binders are analyzed through laboratory tests. Three types of WMA additives ad one commercial rejuvenator named GST were selected to restore the artificial RA. The laboratory performace tests including the penetration test, softening test ad rotary, viscosity （RV） test were carried out. In addition, the Fourier transform infrared spectroscopy （FTIR） test was performed to explore the chemical property of RWMA binders. The results of the performance tests indicate that the rejuvenator GST has the ability to restore the artificial RA; choosing the optimum content of WMA additives and rejuvenator is the key to restoring 100% artificial RA, since the combined effects of them play an important role in determining the basic laboratory performance of RWMA binders. The FTIR tests show that the process of recycling mainly adjusts the chemical component of aged asphalt and no remarkable change is observed in the FTI1R spectra of RWMA binders in terms of chemical functional groups with the introduction of WMA additives.

扭转西北战局时的彭德怀同志

1947年3月，国民党军队向解放区的全面进攻被粉碎后，即改为重点进攻陕甘宁边区和山东解放区。3月13日，胡宗南以第一、第二十九两个整编军、十五个旅的十四万兵力，分左右两路，从洛川、宜川地区向延安大举进犯。

Analysis to the Driving Force Model and Drives Factor on the Utilized Changes of Cultivated Land in Qinghai Lake Area

Using path analysis, correlation analysis, partial correlation analysis and system dynamics method to study the driving force of cultivated land in Qinghai Lake Area, and using gradually regression analysis to establish the driving force model of utilized change of cultivated land. Driving factors, action mechanism and process of utilized change of cultivated land were analyzed, and the differences during all factors were compared. The study provides some decision basis for sustainable utilization and management of land resources in Qinghai Lake Area.

有关高校领导班子建设的几个问题

从我访问过的一些高等院校和从阅读的有关材料中得知,目前高等学校校系两级的领导班子都先后进行了调整。调整后的领导班子在革命化、年青化、知识化、专业化等方面都有明显的变化,尤其在年青化、知识化方面表现得更为突出。调整后的校系领导班子成员,年龄多数在四十五到五十五岁之间。更年青的有三十多岁的,年老的也有超过六十岁的。

One-step hydrothermal synthesis of Cu-SAPO-34/cordierite and its catalytic performance on NO_x removal from diesel vehicles

Cu-SAPO-34/cordierite catalysts were prepared via one-step hydrothermal synthesis method and their performances to remove NO x from the diesel vehicle exhaust were evaluated. The morphology, structure, Cu content and valence state were characterized by SEM, XRD, ICP and XPS, respectively. The experimental results show the active component Cu of the catalysts via in situ synthesis could significantly improve the selective catalytic reduction （SCR） activities of NOx and the optimal Cu content is in the range of 0.30%-0.40%（mass fraction）. No N 2 O is detected by gas chromatograph （GC） during the evaluation process, which implies that NOx is almost entirely converted to N2 over Cu-SAPO-34/cordierite catalyst. The conversion rate of NOx to N2 by NH3 over catalyst could almost be up to 100%in the temperature range of 300-670 ℃with a space velocity of 12000 h-1 and it is still more than 60% at 300-620 ℃ under 36000 h-1. The catalysts also show the good hydrothermal and chemical stability at the atmosphere with H 2 O.

导读前线

两个月的暑期长假已经来临,广大的大中小学生们都在为自己的暑假计划着。准备旅游的您,是否需要一些必备的旅行保健常识呢?不用着急,在这一期的杂志中,我们为您准备多多……希望您度过一个快乐的暑假。