咸水灌溉下土壤水盐动态和作物生长研究进展

我国淡水资源短缺且分布不均,供求矛盾突出,合理开发利用咸水资源、增辟灌溉水源将成为解决水资源危机的重要途径之一。本文从以下几个方面对国内外咸水资源灌溉利用的研究进展进行了综述,以期为咸水安全灌溉提供指导。(1)咸水灌溉对土壤水盐运移的影响,主要包括咸水灌溉后不同土层土壤水盐分布规律、不同灌溉水矿化度对土壤水盐运移的影响、灌溉方式对土壤盐分积累的作用;(2)咸水灌溉对作物生长的影响,主要包括咸水灌溉与作物产量、品质的关系;(3)咸水灌溉对作物生理变化的影响及其作用机理,主要包括咸水灌溉对植株脯氨酸含量、抗氧化酶活性、丙二醛含量、叶绿素含量及光合作用的影响。

麦田秸秆覆盖的节水增产机理及覆盖技术

1987～1990年度的试验表明:农田秸秆覆盖是一项节水量大、节水效果很好的非工程措施,它能产生调节地温、蓄水保墒、保护表土、抑制杂草、培肥地力、改良土壤等良性生态效应,使农作物产量大幅度提高,从而降低了耗水系数;同时能把减少的棵间蒸发无效水,通过“土壤水库”的调节,转化为叶面蒸腾有效水,提高了用水效率.若按经济灌溉制度进行灌水,则调节效果更加显著.

河南省粮食安全保障研究

利用GIS技术和作物生长机理模型对河南省的粮食生产潜力进行了测算 ,并在对粮食需求量分析的基础上 ,得出通过保护耕地数量和提高土地生产力 ,河南省不仅可以解决自身的粮食安全保障问题 。

Soil-structure interaction of unsymmetrical trench installation culvert

The computation of the design load on culverts in the current Chinese General Code for Design of Highway Bridges and Culverts （CGCDHBC）is primarily based on the linear earth pressure theory, which cannot accurately reflect the changes in vertical loads on trench installation culverts. So the changes in vertical earth pressure and soil arching effect in the backfill for an unsymmetrical trench installation culvert are studied based on a full scale experiment and finite element （FE） simulation. The variation laws of foundation pressure and settlement are also analyzed. Meanwhile, the influence of eccentric load induced by an unsymmetrical trench installation on the interaction of a soil- structure system is discussed. Results show that soil arch is formed when the backfill on the culvert reaches a certain height. It can relieve the earth pressure concentration on the crest of the culvert, but it is instable. The earth pressures obtained by full scale experiment and numerical simulation are greater than those calculated by the current CGCDHBC method. The eccentric load effect on the culvert has a significant influence on the stress states and deformation of the soil-structure system.

Effects of Excessive Mg2+ on the Germination Characteristics of Crop Seeds

[ Objective ] The research aimed to reveal theeffects of excessive Mg^2＋ on the germination characteristics of maize and soybean. [ Method ] Eleven concentration gradients of Mg^2＋ including 0, 40, 80, 120, 160,200,240,280,320,360 and 400 mmol/L were set up to study the effects of different treatments on such indices as the germination potential, germination rate, fresh weight, dry weight, root length, plant height and stem diameter of maize and soybean. [ Result] With the increasing of Mg^2＋ concentration, the germination of maize delayed and the germination rate of soybean obviously decreased, reaching the significant difference at 0.05 level. When Mg^2＋ concentration increased, the fresh weight and dry weight of maize and soybean decreased, but maize and soybean showed some adaptability. The growth of radicles and seedlings in maize and soybean were obviously inhibited by Mg^2＋ , and atrophy and dysplasia phenomena appeared. [ Conclusion] Excessive Mg^2＋ stress has different effects on the germination potential and germination rate of different crops and has obvious poisoning effects on the root and stem growth of crops.

Primary Mechanisms for Novel Compound Pivanampeta Against Atherosclerosis in Rat and Rabbit Model of Atherosclerosis

Aim To investigate the anti-atherosclerotic mechanisms of the novel compoundpivanampeta in the early and later stages of atherosclerosis evolution. Methods Rats or rabbits wererandomly assigned to the control, the model and the pivanampeta-treated groups. The rats or rabbitsin the model group and the pivanampeta-treated group were fed with hypercholesterol diet. Thecarotids of rabbits were cut into pieces and stained with HE. The rat or rabbit serum levels of TC,LDL-CHO, HDL-CHO, IL-8, ET-1, PGI_2, TXA_2, and NO were assayed. The expressions of MCP-1 and IL-8mRNA on rabbit carotid were determined by semi-quantitative RT-PCR. Results Pivanampeta exerted aninhibitory effect on TXA_2 formation without PGI_2 production in the early and later stages ofatherosclerosis. The significantly increased release of NO and the decreased release of IL-8 in theanimals in pivanampeta-treated group were both detected in the rat atherosclerosis model. In therabbit atherosclerosis model the expressions of IL-8 and MCP-1 mRNA in pivanampeta-treated groupwere decreased significantly. However, the treatment with pivanampeta had no effect on the levels ofplasma cholesterol, MDA and SOD. Conclusion The increase of serum NO contents and the decrease ofplasma TXA_2 level, as well as its inhibition of expression of IL-8 and MCP-1 are probably involvedin the mechanisms underlying the anti-atherosclerotic effects of pivanampeta.

Methanol Perturbing Modeling Cell Membranes Investigated using Linear and Nonlinear Vibrational Spectroscopy

Cell membranes play a crucial role in many biological functions of cells. A small change in the composition of cell membranes can strongly influence the functions of membrane-associated proteins, such as ion and water channels, and thus mediate the chemical and physical balance in cells. Such composition change could originate from the introduction of short-chain alcohols, or other anesthetics into membranes. In this work, we have applied sum frequency generation vibrational spectroscopy （SFG-VS）, supplemented by attenuated total reflectance Fourier transform infrared spectroscopy （ATR-FTIR）, to investigate interaction between methanol and 1,2-dimyristoyl-d54-sn-glycero-3-phosphocholine （d54-DMPC） lipid bilayers. Lipid＇s hydrocarbon interior is deuterated while its head group is hydrogenated. At the same time, CH3 symmetric stretch from methanol and lipid head amine group has different frequency, thus we can distinguish the behaviors of methanol, lipid head amine group, and lipid hydrocarbon interior. Based on the spectral feature of the bending mode of the water molecules replaced by methanol, we determined that the methanol molecules are intercalated into the region between amine and phosphate groups at the lipid hydrophilic head. The dipole of CH3 groups of methanol and lipid head, and the water O-H M1 adopt the same orientation directions. The introduction of methanol into the lipid hydrophilic head group can strongly perturb the entire length of the alkyl chains, resulting that the signals of CD2 and CD3 groups from both leaflets can not cancel each other.

Popularization and Application of Haidaosu(5% Amino-oligosaccharin)as a Plant Immunity Inducer in Main Crops Cultured by Corps

The plant immunity inducer, amino-oligosaccharin, has remarkable effects in disease resistance, cold tolerance, growth promotion, yield increase and quality improvement. This paper introduced the action mechanism of amino-oligosaccharin, its main application effects on crops and application techniques. In 2013-2014, ex- periments were conducted on a variety of crops at multiple locations by Xinjiang Corps as well as popularization and application in 2013-2014, and it was shown by the popularization and application that the application of amino-oligosaccharin could promote plant growth, reduce the incidence of crop diseases and improve crop yield and product quality.

Boiling Heat Transfer in an Acoustic Cavitation Field

An experimental study has been carried out investigatesystematically the effects of acoustic cavi- tation parameters andfluid subcooling on boiling of acetone around a horizontal circulartube. The experimental results show that acoustic cavitation enhancedremarkably the boiling heat transfer and decreased the incipientboiling superheat and that cavitation bubbles effect on boiling heattransfer reduced with cavitation distance. For boiling curves in aform of h-q', elevated cavitation distance shift nucleate boilingcurves to the right of the cor- responding ordinary pool boilingcurve. The associated mechanism of heat transfer enhancement isanalyzed with the consideration of cavitation bubble influence onvapor embryo.

Distribution,Properties,Land Use and Management of Mollisols in South America

Mollisols are common in South America. They cover about 8.87 × 107ha, 1.3 × 107ha and 4.3 × 106ha in Argentina, Uruguay and Southern Brazil respectively, which is 11.5% of the world total. Most of South American Mollisols were developed on Pleistocene and Holocene sediments and lie within the limits of the temperate zone, though the extreme north is bordering subtropical and the extreme south is within a cold-temperate zone. All suborders of Mollisols occur in Argentina, the most extensive being Udolls followed by Ustolls, whereas only Udolls, Aquolls and Albolls occur in Uruguay. Vertisols in Uruguay have many properties similar to Mollisols, and the occurrence of Vertisols is strongly associated with Mollisols. The Pampean Mollisols are a significant component of the global breadbasket of modem times. The main Argentine crops are wheat, corn, sorghum, barmy, soybeans and sunflower, while Mollisols in Uruguay remain mostly dedicated to cattle and sheep grazing though crop production has been increasing very rapidly in the last decade. Throughout South America, research has shown that Mollisols are experiencing losses of soil organic matter and nutrients, and degradation of physical properties after long cropping periods, resulting in soil scientists calling for increased conservation practices to reduce future losses and a deterioration of soil quality, and thus a more sustainable agriculture in the region.

Health-related quality of life of 256 recipients after liver transplantation

AIM:To investigate health-related quality of life(HRQoL) and psychological outcomes in 256 adults who had undergone liver transplantation(LT).METHODS:A stratified random sampling method was used in this follow-up multicenter study to select a representative sample of recipients undergoing either living donor liver transplantation(LDLT) or deceased donor liver transplantation(DDLT).HRQoL was measured by using the Chinese version of Medical Outcome Study Short Form-36(SF-36),and psychological outcomes by using the beck anxiety inventory(BAI) and the self-rating depression scale(SDS).Clinical and demographic data were collected from the records of the Chinese Liver Transplant Registry and via questionnaires.RESULTS:A total of 256 patients were sampled,including 66(25.8%) receiving LDLT and 190(74.2%) undergoing DDLT;15(5.9%) recipients had anxiety and four(1.6%) developed severe depression after the operation.Compared with LDLT recipients,DDLT patients had higher scores in general health(60.33 ± 16.97 vs 66.86 ± 18.42,P = 0.012),role-physical(63.64 ± 42.55 vs 74.47 ± 36.46,P = 0.048),roleemotional(61.11 ± 44.37 vs 78.95 ± 34.31,P = 0.001),social functioning(78.60 ± 22.76 vs 88.16 ± 21.85,P = 0.003),vitality(70.30 ± 15.76 vs 75.95 ± 16.40,P = 0.016),mental health(65.88 ± 12.94 vs 71.85 ± 15.45,P = 0.005),physical component summary scale(PCS,60.07 ± 7.36 vs 62.58 ± 6.88,P = 0.013) and mental component summary scale(MCS,52.65 ± 7.66 vs 55.95 ± 10.14,P = 0.016).Recipients > 45 years old at the time of transplant scored higher in vitality(77.33 ± 15.64 vs 72.52 ± 16.66,P = 0.020),mental health(73.64 ± 15.06 vs 68.00 ± 14.65,P = 0.003) and MCS(56.61 ± 10.00 vs 54.05 ± 9.30,P = 0.037) than those aged ≤ 45 years.MCS was poorer in recipients with than in those without complications(52.92 ± 12.21 vs 56.06 ± 8.16,P = 0.017).Regarding MCS(55.10 ± 9.66 vs 50.0 ± 10.0,P < 0.05) and PCS(61.93 ± 7.08 vs 50.0 ± 10.0,P < 0.05),recipients scored better than the Sichuan general and had improved overall QoL compared to patients with chronic diseases.MCS and PCS significantly correlated with scores of the BAI(P < 0.001) and the SDS(P < 0.001).CONCLUSION:Age > 45 years at time of transplant,DDLT,full-time working,no complications,anxiety and depression were possible factors influencing postoperative HRQoL in liver recipients.

Role of Nitrogen and Nutrients in Crop Nutrition

Nutrition is an important factor for the growth and development of plants. Among the main nutritional elements, there are nitrogen （N） and calcium （Ca）. The N comes from two forms of inorganic ions, ammonium （NH4＋） and nitrate （NO3） whose functions in the plant are the increase in leaf area and improving the succulence of many crops, among other essential physiological processes. Both the deficit and excess NO3- have a negative impact on plants increasing susceptibility to insect pests and pathogens, while Ca as divalent ion absorbed Ca2＋ plays an important role in control of physiological disorders and the resistance of plants to diseases to increase the mechanical strength. The N and Ca have a close relationship in the nutritional role of the plant, because the Ca absorption acting nitrates, so that a proper balance affects plants better growth and higher strength.

Analysis of soft rock mineral components and roadway failure mechanism

The mineral components and microstructure of soft rock sampled from roadway floor in Xiagou pit are determined by X ray diffraction and scanning electron microscope. Combined with the test of expansion and water softening property of the soft rock, the roadway failure mechanism is analyzed, and the reasonable repair supporting principle of roadway is put forward.

XU Xiaohui,CHEN Hui'e and WANG Gangcheng College of Construction Engineering,Jilin University,Changchun 130026,China

On the basis of geological investigating work and experimental studies on slide zone soil of one landslide in Tibet,the authors analyzed granulometric composition,clay mineral composition and physical and mechanical properties for the soil in the slide zone.The soil samples are gravel containing fine particle.Particles larger than 2 mm occupy the main proportion with the content 51.5%--68.5%.The relative content of clay minerals is low.The clay minerals are illite smectite mixed layer and kaolinite,and their relative contents are 6%--13% and 4%-11%,respectively.The main mineral ingredient is quartz and the relative content is over 30%.Therefore,the soil’s hydrophily is poor.The cohesion and internal friction angle are high,causing preferable physical-mechanical features of slide zone soil.On the basis of the obtained data,the landslide stability is evaluated by means of limit equilibrium method.The safety factors are 3.191 and 1.92 respectively under both natural and normal water level conditions.The study results show that the landslide is stable.It can provide the appropriate basis and reference for landslide stability evaluation and landslide control in Tibet.

The influence of anoxia design and change aerations time on the treatment from coke plant wastewater

According to a great deal of experimental findings and the oretical analysis, theperformance of SBR process treating organic substance and ammonia was presented for different operating pattern and aeration time.When the operation mode is feeding water,anoxie mixing 2.5 h, settlement, and draining for 1.5 h, the coke plant wastewater can be treated well by the SBR method.

Preliminary studies on the mechanism of blistering cupping therapy

Blistering cupping therapy, as a new type of cupping therapy, has attracted more and more attention of clinical doctor and scholars in home and abroad. Blistering cupping therapy achieves better effects through the formation of blistering fluid after suction. However, it is still controversial whether cupping induced blisters are beneficial to recovery of diseases, and the mechanism is still not completely clear. Here on the basis of the traditional cupping method, we aimed to identify the mechanism of blistering cupping from the levels of biomechanics and molecular biology. The negative pressure attraction induced by cupping suck should be of value in increasing pain threshold and relieving pain as well as improving the blood circulation and metabolism. Furthermore, the blistering fluid induced by cupping was the inflammatory substance actually that discharged through the superficial lymphatic vessels, including immunoglobulin, lysozyme, erythrocytes, etc. which could cause the autogenetic inflammatory reaction of selected cupping area, and further activated certain immune pathways including anti-oxidation, anti-apoptosis, tissue repairing and metabolic regulation. Besides, the formation of scar induced by blistering cupping was not only the result of excessive inflammatory response, but also involved in mobilizing the immune response.

INTERACTION MECHANISM OF ORGANIC MATTER WITH GEL TYPE POLYSTYRENE STRONGLY BASIC ANION EXCHANGE RESIN AND REGENERATION OF THE ORGANISM FOULED RESIN Ⅰ.The interreaction mechanism between strongly basic anion exchange resin and organic matter

It was generally considered that contamination of the gel type polystyrenestrong basic anion exchange resin by organic matter in natural water is the result ofion exchange and Van der waal's adsorption on it. On the basis of laboratory and industrial experiments, this paper confirmed that the interreaction between organicmatter and resin polymer matrix is primarily controled by a Van der waal's adsorption.

van der Waals Interactions in Bimolecular Reactions

The van der Waals (vdW) interaction is very important in fields of physics, biology and chemistry, and its role in reaction dynamics is an issue of great interest. In this review, we focus on the recent progresses in the theoretical and experimental studies on the vdW interaction in bimolecular reactions. In particular, we review those studies that have advanced our understanding of how the vdW interaction can strongly influence the dynamics in both direct activated and complex-forming reactions, and further extend the discussion to the polyatomic reactions involving more atoms and those occurring at cold and ultracold temperatures. We indicate that an accurate description of the delicate vdW structure and long-range potential remains a challenge nowadays in either ab initio calculations or the fitting of the potential energy surfaces. We also present an explanation on the concept of vdW saddle proposed by us recently which may have general importance.