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Under natural circulation conditions, the reverse flow phenomenon may occur within some U-tubes. This will result in the flow resistance coefficient of the steam generator (SG) obviously larger than that under forced circulation conditions, and the decrease of nature circulation capability in the primary circuit (PC). The heat transfer characteristics between the secondary circuit (SC) and PC in the SG are very complicated. Expressly, there is an obvious preheating section due to a certain fluid under-heat degree at the inlet of the ascending passage in the SC. In this paper, a type of marine SG is studied and a theoretical model of the SC single channel is established for the preheating sections (PS) corresponding to the ascending section (AS) and the descending section (DS) of U-tubes. Based on this model, the reverse flow characteristics of U-tubes are researched, and the influence of SC operating pressure, U-tubes pitch and circulation ratio on the U-tube reverse flow characteristics are calculated and analyzed. The results show that compared with the existing reverse flow calculation methods, the temperature distribution in the PS of SC increases exponentially and remains unchanged in the boiling section, and the critical flow rate is relatively higher. The increase of SC operating pressure and U-tubes pitch will decrease the mass flow rate of reverse flow, and the influence of circulation ratio has the opposite conclusion.

A hydroponic experiment was carried out to study the effects of UV-B radiation (5.0kJ/m2) on root morphology and root exudates in the local rice variety Baijiaolaojing in a terraced field in the Yuanyang region of China. It was observed that UV-B radiation had the following impact on rice physicochemical properties (1) significant inhibition in both root biomass and the whole biomass of rice, (2) significant increase in the free amino acid and total phenol content secreted by roots on the 40th and 60th day of growth, (3) significant increase in the soluble sugar content in all three growth phases (4) significant increase in oxalic acid and succinic acid, (5) significant decrease in malic acid. The content of tartaric acid was not significantly impacted by the two treatments (natural light 0 kJ/m2, UV-B radiation (5.0kJ/m2). Therefore, UV-B enhancement significantly affects the content of low molecular organic acids in rice, which is closely related to its altered root morphology.

Under natural circulation conditions, the primary circuit of a steam generator (SG) has a tendency to occur flow instabilities. These instabilities due to reverse flow in some vertically inverted U-tubes will increase the flow resistance coefficient and reduce the natural circulation ability in the primary system. To address the lack of existing research on transient reversed flow, in the present work, the reverse flow characteristics in the U-tubes of vertically inverted U-tube steam generator (UTSG) are investigated experimentally and theoretically. By gradually rising the inlet plenum mass flow of steam generator simulator at a constant fluid temperature, the reverse flow characteristics are observed in a thermal hydraulic test facility. Based on the experiment, the flow and heat transfer model in U-tubes are established to study the effects of change rate of mass flow and flow distribution on the reverse flow inside the UTSG. The experimental and theoretical results demonstrate that during the transient process, some U-tubes get reverse flow with the continuous decrease of mass flow and the reverse flow U-tubes also have a significant impact on other U-tubes, which results in a maximum temperature drop of about 35%. With the decrease of mass flow in U-tubes, the critical mass flow of the UTSG will increase and the reverse flow will occur more easily during the transient process. The results can provide a basis for avoiding the occurrence of reverse flow in actual SGs and improving the ability of natural circulation.

Field experiments were conducted in Dianchi basin to study the effects of straw mulching on the quantity of ammoniated bacteria, actinomycetes, and fungi in maize and broccoli soil, using dilution plate counting method. The results showed that: (1) Compared with bare soil and uncovered soil, plastic mulching and straw mulching could increase the number of microorganisms in Maize soil. Straw mulching could significantly increase the number of fungi in maize soil, reaching 6.5×104 CFU·g−1 dry soil, which was 2.0, 1.4 and 2.7 times as much as that of plastic mulching, uncovered and bare soil respectively. The effects of straw mulching and plastic mulching on the number of other types of microorganisms in maize soils were not significantly different. (2) Compared with bare soil, straw mulching could increase the number of fungi in broccoli soil by 83%, and plastic mulching could increase the number of actinomycetes and fungi. Straw mulching could increase the number of microorganisms in soils, which is of great significance to clarify the microbial mechanism of straw mulching to reduce non-point source pollution.

Neutron spatial-time kinetics equations are composed of multiple mutually coupling variables, and solving the equations is relatively complex and time-consuming. Thus, it is difficult to meet the demand for actual fast calculations. In the present work, the quasi-static orthogonal (QSO) method is proposed to solve space-time reactor neutron kinetics equations for a cylindrical homogeneous core. Under the conditions of quasi-static approximation, the neutron flux density is decomposed into a range function and shape function using the factorization method. The analytical solutions in the axial and radial directions of the shape function are obtained using this QSO method. Also, the range function is transformed into the form of a point reactor model for the series solutions. Then the analytical solutions of the three-dimensional spatial-time reactor neutron kinetic equations are derived under non-steady state conditions. Applying the results to the operating reactors departs from the steady state conditions, and the variation of neutron flux density with time and space is obtained. Compared with other analytical methods and numerical solutions, this QSO method is relatively simple and effective under the conditions of the non-steady and delayed neutron impact.

Pot experiments were carried out to study the effects of intercropping by Chenopodium ambrosioides L. and maize on the root exudates of soluble sugar and amino acids, in order to understand the relationship between root exudates and cadmium accumulation in plants. The results showed that, compared with monoculture system: (1) after intercropping with maize, the content of soluble sugar in root exudates of C. ambrosioides increased by 106.54%, the content of amino acids increased by 52.73%, the available Cd content in rhizosphere soil increased by 12.09%, the root Cd content increased by 15.52%. (2) The content of soluble sugar in root exudates of maize increased by 40.41%, the content of amino acids increased by 70.59%, the available Cd content in rhizosphere soil increased by 29.35%, the shoot Cd content of maize increased by 208.26%. (3) There were significantly posotive correlations between the contents of soluble sugar and amino acids secreted by C. ambrosioides and maize roots and the available Cd content in soil. In addition, there was a significant positive correlation between the available Cd content in soil and the Cd contents in the shoots and roots of plants. The results showed that the increase of soluble sugar and amino acid content of root exudates under the intercropping system caused the change of the available Cd content in the rhizosphere soil, which eventually changed the accumulation of Cd in the shoot and root of C. ambrosioides and maize.

Wong Kar Wai is a Hong Kong film director. However, his films cross not only the regional boundary between Hong Kong and Mainland China, but also the border between China and foreign countries. He brings Hong Kong film to the world. His films are representative of the nostalgia. He likes to create in his films a nostalgic atmosphere of Shanghai, his hometown. In this ambience, we can see his desire to seek his roots. His films often depict the Hong Kong people’s authentic mental state at different times. The films in the 1990s show the anxiety of Hong Kong people when the return of Hong Kong (1997) approach. The trilogy of 1960s shows the desire of Hong Kong people for seeking their roots. That's why his films have a good reputation among the audience and the critics in Hong Kong, even if the box office is usually low. Hong Kong people prefer stories that tell their lives and their true feelings. The Mainland Chinese has a different taste of the people of Hong Kong. They like the style and the stories of Wong Kar Wai. The Grandmaster (2013) was particularly admired. The theme of the Sino-Japanese war is a common theme to show the love for the motherland and the national spirit. How to shoot this theme by a Hong Kong director is also a focal point for the Mainland public. And Chinese thoughts are shown in this film. The Chinese philosophy influences not only the thoughts of the Kungfu masters of this film, but also the thoughts of Mainland audience. Wong has a good reputation in France, particularly at the Cannes film festival. He is a big fan of the New Wave. Not only the theme, but also the shooting style is influenced by the films of the New Wave. The theory of author’s film is often show in his films. The permanent theme of his films is the communication of people in modern life. But the films with complicates stories are less admired than those with the simple stories. Therefore, the story of Mr. Chow and Mrs. Su of In the Mood for Love (2000) and 2046 (2004) is much preferred by the French audience. In the films of Wong Kar Wai, we can find out the references of foreign films, and the typical Chinese characteristics. This is the reason why his films are admired by the regional audience and the foreign audience as well.; Wong Kar Wai est un cinéaste hongkongais, mais ses films dépassent non seulement la frontière régionale entre Hong Kong et la Chine continentale, mais aussi la frontière entre la Chine et l’étranger. Il apporte le cinéma régional de Hong Kong au monde. Ses films sont représentatifs pour montrer la nostalgie. Il aime recréer dans ses films une ambiance nostalgique de Shanghai, sa ville natale. Dans cette ambiance, on peut voir son envie de chercher ses racines. Ses films décrivent souvent l’état mental authentique des Hongkongais aux époques différentes. Les films sortis dans les années 1990 montrent l’anxiété des Hongkongais quand la Rétrocession de 1997 s’approche ; la trilogie des années 1960 montrent la volonté des Hongkongais de chercher leurs racines. C’est pourquoi ses films ont une bonne réputation parmi les spectateurs et les critiques hongkongais même si les box-offices sont faibles. Les Hongkongais préfèrent les histoires qui montrent leur vie et leurs sentiments réels. Les Chinois continentaux ont un goût différent des Hongkongais. Les spectateurs continentaux aiment le style et les histoires des films de Wong. The Grandmaster (2013) est particulièrement admiré. Le thème de la guerre sino-japonaise est un thème populaire pour montrer l’amour pour la patrie et l’esprit national. La façon de présenter ce thème par un réalisateur hongkongais est aussi un point d’attraction pour le public continental. Et la pensée chinoise est beaucoup montrée dans ce film. La philosophie influence non seulement les pensées des maîtres de kung-fu du film, mais aussi celles des spectateurs continentaux. Wong a une bonne réputation en France, particulièrement au Festival de Cannes. Il est un grand admirateur de la Nouvelle Vague. Non seulement le thème, mais aussi la façon de tourner les films est influencée par les films de la Nouvelle Vague. La théorie du film d’auteur apparaît beaucoup dans ses films. Le thème permanent de ses films est celui de la communication des personnes dans la vie actuelle. Mais les histoires compliquées sont moins admirées par rapport aux histoires plus simples. Donc l’histoire de monsieur Chow et madame Su d’In the Mood for Love (2000) et de 2046 (2004) est préférée par les spectateurs français. Dans les films de Wong Kar Wai, on peut découvrir les références des films étrangers, et aussi les caractéristiques typiquement chinoises. C’est bien la raison pour laquelle ses films sont admirés par les spectateurs régionaux et en même temps par les spectateurs étrangers.

Gene expression levels of the four common drivers using data from GTEX. (DOCX 280 kb)

Survival analysis for 353 patients with only gene expression data using the four common drivers. (DOCX 24 kb)

A potential problem of reversed labels between tumor and normal in the aCGH data of 32 patients. Intensity values in these samples are suggested to be reversed before any further analysis. (DOCX 55 kb)

In this study, we constructed a visible model for drug/gene dual delivery. Firstly, we prepared a series of pyrene fluorophore bearing cationic amphiphiles (Py-amines), which could be further employed as amphiphilic gene carriers and antitumor polyamine drug models. Then, the Py-amines fluorescent amphiphiles were utilized to bind/load plasmid DNA via electrostatic interactions to form nano-sized particles in aqueous solution. The average size, zeta potential and morphology of the self-assembled Py-amines/pDNA complexes were found to be largely dependent on the molecular structures of Py-amines amphiphiles. Moreover, the Py-amines and their pDNA complexes showed an evident cell proliferation inhibition capability in H1299 (human lung cancer) cells. Notably, the lysosomal localization of the Py-amines/pDNA complexes could be directly visualized using fluorescence microscopy in vitro. In summary, this current study could provide new and visible approach to design polyamine-based anti-tumor drug/plasmid DNA dual delivery systems, which could facilitate a greater understanding of the intracellular trafficking/localization of polyamine-based cationic gene/drug payloads.

In this paper, the relationship between the liquid structure and the corresponding solidified microstructure of an Al-Si-Mg-P alloy was studied. Experimental results show that Mg can reduce the phosphorous-modification effect if it was added after adding Al-P alloy. However, when it is added before adding Al-P alloy, Mg has no effect on the phosphorous-modification. It is considered that the difference in liquid structure induced by changing the adding order of Mg should be responsible for the above phenomenon, and was investigated by ab initio molecular dynamics simulation (AIMD). It was believed that the high-active Mg atoms could bond P atoms to form P-Mg clusters and then reduce the modification effect of AlP, when pure Mg was added into the prepared Al-Si-P melt. When the pure Mg was added into Al-Si melt before adding Al-P alloy, the Mg atoms would be first occupied by Si atoms to form Mg-Si clusters, and thus lose the ability to eliminate P-Al clusters which dissolve into melt later, leading to a good phosphorous-modification effect.

Generation of haploid gametes by meiosis is a unique property of germ cells and is critical for sexual reproduction. Leaving mitosis and entering meiosis is a key step in germ cell development. Several inducers or intrinsic genes are known to be important for meiotic initiation, but the regulation of meiotic initiation, especially at the protein level, is still not well understood. We constructed a comparative proteome profile of female mouse fetal gonads at specific time points (11.5, 12.5, and 13.5 days post coitum), spanning a critical window for initiation of meiosis in female germ cells. We identified 3666 proteins, of which 473 were differentially expressed. Further bioinformatics analysis showed that these differentially expressed proteins were enriched in the mitochondria, especially in the electron transport chain and, notably, 9 proteins in electron transport chain Complex I were differentially expressed. We disrupted the mitochondrial electron transport chain function by adding the complex I inhibitor, rotenone to 11.5 days post coitum female gonads cultured in vitro. This treatment resulted in a decreased proportion of meiotic germ cells, as assessed by staining for histone γH2AX. Rotenone treatment also caused decreased ATP levels, increased reactive oxygen species levels and failure of the germ cells to undergo premeiotic DNA replication. These effects were partially rescued by adding Coenzyme Q10. Taken together, our results suggested that a functional electron transport chain is important for meiosis initiation. Our characterization of the quantitative proteome of female gonads provides an inventory of proteins, useful for understanding the mechanisms of meiosis initiation and female fertility.

Vacuum pressure sensors play a significant role in industry and scientific research. However, there are still many challenges for further application of vacuum pressure sensors due to their complex fabrication and high cost. In this work, we have fabricated a graphene vacuum pressure sensor by one-step laser scribing within 25 min. The resistance of the sensor decreases with declining vacuum pressure. Four linear segments are obtained in the relationship between the resistance response and the vacuum pressure ranging from 7.5 × 10−4 Torr to 2.35 Torr at room temperature. Besides, the graphene sensor exhibits a high sensitivity of 1.2 × 10−2 Torr−1 and a rapid response time of 9 s, which are superior to previously reported sensors. The sensing mechanism of the graphene vacuum pressure sensor is investigated. Under the influence of van der Waals interactions between the stacked graphene multilayers, the void space among the neighboring graphene layers reduces with decreasing vacuum pressure, resulting in a decrease of the sheet resistance. The designed graphene vacuum pressure sensor with the distinguished features of high performance, small size, low cost, and simple fabrication shows great feasibility and tremendous potential for vacuum measurement applications.

Polyploidy plays an important role in the evolution of plant genomes. To enable the investigation of the polyploidy events within the genus Anemone, we developed eighteen microsatellite markers from the hexaploid species A. amurensis (Ranunculaceae), and tested their transferability in five closely related species. The number of total alleles (NA) for each resulting locus varied from one to eight. The polymorphism information content (PIC) and Nei’s genetic diversity (NGD) for these microsatellites ranged from 0.00 to 0.71 and 0.00 to 0.91, respectively. For each population, the NA was one to seven, and the values of PIC and NGD varied from 0.00 to 0.84 and 0.00 to 0.95, respectively. In addition, most of these microsatellites can be amplified successfully in the congeneric species. These microsatellite primers provide us an opportunity to study the polyploid evolution in the genus Anemone.

Due to the widespread use of antibiotics, there is a large amount of antibiotics in the soil. After entering the soil, antibiotics will undergo a series of biogeochemical processes under the action of various environmental factors: adsorption, migration, transformation, degradation or enrichment in plants and animals. By summarizing the relevant literature, it was found that the factors that affect the biogeochemical process of antibiotics including the types of antibiotics, temperature, the types of soil and illumination.

In all drugs contaminated with the environment, antibiotic abuse has become a global problem because of its high rate of consumption in veterinary and human medicine, and antibiotic-induced bacterial resistance and toxicological damaged to organisms in the environment are increasingly being studied at home and abroad. In this paper, the residues of antibiotics in soil were introduced, and the ecological toxicological effects of antibiotics were reviewed, and a new idea was provided for future research.

A novel glucose biosensor based on the electrochemical detection of enzymatically generated H 2 O 2 was constructed by the effective immobilization of glucose oxidase (GOD) via glutaraldehyde cross-linking with a poly(thionine) (PTH)-modified Au electrode, followed by coating with a Nafion outer layer to obtain high selectivity. An electrochemical quartz crystal microbalance (EQCM) was used to track various modification procedures. The mass of the deposited PTH via cyclic voltammetric electropolymerization of thionine in aqueous H 2 SO 4 was estimated from the “dry” frequency shift after fully removing the PTH layer via its acidic degradation, allowing us to evaluate the electroactivity per unit mass of PTH. A Nafion/glucose oxidase-glutaraldehyde/poly(thionine)/Au electrode was thus constructed for glucose sensing. We found that the PTH film is a good matrix to immobilize more GOD, and the performance of the constructed sensor is significantly improved compared with its absence, though its mediator effect on the enzyme electrode is negligible. Influence of various experimental parameters on glucose sensing, including the applied potential, solution pH and electroactive interferents, was investigated. At an optimal potential of 0.7 V versus the KCl-saturated calomel electrode (SCE), the glucose biosensors were linear with glucose concentration from 0.005 to ∼5 mmol L −1 , with high sensitivity (13.5 A mol −1 cm −1 ), short response time (within ca. 10 s) and good anti-interferent ability. The Michaelis constant ( K m app ) of the immobilized GOD was estimated to be 5.47 mmol L −1 . The biosensor exhibited good storage stability, i.e., 83% of its initial response was retained after 1-month storage in a pH 7.0 phosphate buffer at 4 °C. The effective enzymatic specific activity (ESA, defined as enzymatic activity per gram of enzyme) of immobilized GOD was estimated to be 6.85 kU g −1 on the basis of the mass of immobilized GOD (from EQCM) and the quantity of hydrogen peroxide as the product of the enzymatic reaction (from amperometric detection), and the leakage of H 2 O 2 from the Nafion/GOD-GA/PTH/Au enzyme electrode at the detection potential, as characterized by a scanning electrochemical microscope (SECM), was found to be an important factor influencing the ESA estimation.

We present a simple and effective strategy for high yield synthesis of well-dispersed, core–shell Au–Pt nanodendrites (CS Au–Pt NDs) via overgrowth of platinum on in situ 5.5 nm gold nanoparticles in water at room temperature. The sizes of the resulting CS Au–Pt NDs are 14 nm, which should be the smallest so far to the best of our knowledge. The average dimensions of the small Pt branches on the Au nanoparticle surfaces are about 2.6 nm × 4.2 nm, which lead to a significantly increased electrochemically active surface area (up to 35.2 m2 g−1). It is found that the morphology of CS Au–Pt NDs is dependent on the reaction conditions such as the incubation time of citrate–HAuCl4 solution, the mixing time of citrate–HAuCl4–K2PtCl4 solution before AA addition, and Pt-to-Au and AA-to-Pt molar ratios. In comparison with commercial Pt black (0.12 A mgPd−1), the resulting Au–Pt5 NDs show a superior catalytic activity towards methanol oxidation (0.45 A mgPd−1) due to the electronic interaction between the Au cores and Pt branches in bimetallic Au–Pt NDs and the high fraction of atomic steps, kinks, and corner atoms on the surfaces of the Pt branches.

Glucose oxidase (GOD) was codeposited into a polymer grown from oxidation of dopamine (DA) at an Au electrode in a neutral phosphate aqueous solution for the first time. The electrochemical quartz crystal impedance analysis (EQCIA) method was used to monitor the GOD-immobilization process. Effects of concentrations of phosphate buffer, DA and GOD were investigated, and the optimal concentrations were found to be 20.0 mM phosphate buffer (pH 7.0), 30.0 mM DA and 5.00 mg ml−1 GOD. A glucose biosensor was thus constructed, and effects of various experimental parameters on the sensor performance, including applied potential, solution pH and electroactive interferents, were examined. At an optimal potential of 0.6 V versus the KCl-saturated calomel electrode (SCE), the current response of the biosensor in the selected phosphate buffer (pH 7.0) was linear with the concentration of glucose from 0.05 to 9 mM, with a lower detection limit of 3 μM (S/N = 3), short response time (within 15 s) and good anti-interferent ability. The Michaelis constant ( K m app ) was estimated to be 9.6 mM. The biosensor exhibited good storage stability, i.e. 96% of its initial response was retained after 7-day storage in the selected phosphate buffer at 4 °C, and even after another 3 weeks the biosensor retained 86% of its initial response. In addition, the enzymatic specific activity and enzymatic relative activity of the GOD immobilized in the polymer from dopamine oxidation (PFDO) were estimated from the EQCIA method to be 1.43 kU g−1 and 3.7%, respectively, which were larger than the relevant values obtained experimentally using poly(o-aminophenol) and poly(N-methylpyrrole) matrices, suggesting that the PFDO is a better matrix to immobilize GOD.

The immobilization of glucose oxidase (GOD) via its dip-dry coating on a Prussian blue (PB) modified Au electrode followed by deposition of an outer poly(o-phenylenediamine) (PoPD) film and then glutaraldehyde (GA) cross-linking was investigated for amperometric glucose sensing, based on the reduction of enzymatically generated H2O2 catalyzed by the electroactive PB layer of the PoPD/GOD-GA/PB/Au electrode. The quartz crystal microbalance (QCM) was used to monitor various electrode-modification processes, and the effective enzymatic specific activity (ESA, defined as enzymatic activity per gram of enzyme) of immobilized GOD was estimated based on the mass of immobilized GOD (from QCM) and the quantity of hydrogen peroxide as the product of the enzymatic reaction (from amperometric detection) for the first time. The ESA of native GOD under our experimental conditions was also estimated via amperometric detection of enzymatically generated H2O2 at a PB-modified Au electrode. Effects of various experimental parameters on glucose sensing, including the applied potential, solution pH and electroactive interferents, were investigated. At an optimal potential of −0.05 V versus saturated KCl calomel electrode (SCE), the current response of the biosensor in the selected phosphate buffer (pH 7.0) was linear with glucose concentration from 0.05 to 10 mmol L −1 , with detection limit of 8 mol L −1 , short response time (within ∼5 s) and good anti-interferent ability. The Michaelis constant ( K app ) of the immobilized GOD was estimated as 19.6 mmol L −1 . The biosensor exhibited good storage stability, i.e., 88% of its initial response was retained after 30-day storage in pH 7.0 phosphate buffer at 4 ◦ C. Since the present sensor-fabrication platform is rather general and advantageous in saving biochemical reagents, it is recommended for the development of other biosensors based on other substrate electrode materials, e.g. glassy carbon that has been tested in this work with satisfactory results. © 2005 Elsevier B.V. All rights reserved.

It has been shown that the traditional small deformation plasticity can be transplanted to the finite deformation plasticity by using the logarithmic strain measure only. In this way, the mathematical problem of how to find the derivative of a tensor function aris-es. In this paper, a general method for finding the derivative of a tensor function is proposed. Several metai forging examples are given. During the calculation, the mesh regeneration is not even invoked.

Multi-crystal metals have the property of volume conservation in the plastic state. In the infinitesimal deformation plasticity the strain tensor can be split into a deviator part and a volumetric part. The vanishing of the first variant of the strain tensor is equivalent to the volume conservation. Furthermore, the split of the strain into an elastic part and a plastic part is also adopted widely. The flow rule is thus established. These two splits are not confirmed in the finite deformation plasticity. The plasticity criterion and the flow rule are thus facing great challenge. There are various definitions of strain measures in the finite deformation theory. Though the choosing of strain measure is arbitrary in the elastic problem, it is strongly restricted in the plastic problem. By theoretical and experimental studies, it is shown that the logarithmic strain is the only suitable strain measure in the metal forming problem.

We present a conceptual architecture for adaptive human-computer interface of a PT operation platform based on context-awareness. This architecture will form the basis of design for such an interface. This paper describes components, key technologies, and working principles of the architecture. The critical contents covered context information modeling, processing, relationship establishing between contexts and interface design knowledge by use of adaptive knowledge reasoning, and visualization implementing of adaptive interface with the aid of interface tools technology.

Due to the facts that the spatial moment force is non-conservative and the three components of the finite rotation pseudo vector are not independent, the ordinary variational principle, based on a functional achieving its stationary value, is not suitable for the problem subject to non-conservative loading. The finite element method proposed in this paper is based on the virtual work principle, rigid normal assumption, polar decomposition and total Lagrangian formulation.

Using the kinematic description of the revised Mindlin model, the Lagrangian strain derived by Li and the Fe formulation of the degenerated 3-D solid, we propose an exact finite deformation theory for plate and shell. The theory eliminates the need for the restrictions imposed by the existing simplified theories such as small strains, small rotations or small loading steps. Numerical examples are presented to demonstrate the validity and accuracy of the theory compared with 3-D continuum theory.

A finite deformation model based on the Timoshenko beam theory is proposed for the three dimensional beam structures. The exact Green-Lagrangian strains are derived. The Finite Element formulation and the corresponding algorithm are presented for the model. Numerical examples are given to illustrate its validity and effectiveness.

Based on the kinematic property of the beam, plate and shell structures under finite deformation, we propose that the mechanical model of a rigid line segment is suitable to describe the finite deformation of the structures. Using this model and the finite rotation matrix, the complete forms of the Green-Lagrangian strains of these structures can be derived with a unified point of view.

A finite deformation theory is proposed that can describe precisely, the nonlinear geometric behavior of a two-dimensional beam structure. Unlike the existing nonlinear theories, this theory does away with simplifications such as the assumptions of small displacement, small normal or shearing strain, small rotation, as well as small loading step. The finite element method and its formulation of this theory are deduced. Numerical examples performed by the theory proved it valid and computed results obtained by the theory are independent of loading steps.

Nitrogen (N) cycle is very important for forest ecosystem, and soil N mineralization rate is often used as the index of soil N availability and its losses. Using Close-Top incubation method, we measured the N mineralization rate in soils (0-15 cm) of monsoon evergreen broadleaf forest, seasonal rain forest, rubber plantation, heavily disturbed seasonal rain forest, Millettia laptobotrya secondary forest and upland rice field. The results showed that the net N mineralization rate and N nitrification rate were decreased in the sequence of heavily disturbed seasonal rain forestMillettia laptobotrya secondary forestseasonal rain forestmonsoon evergreen broadleaf forestrubber plantationupland rice field. Rubber plantation and upland rice field were the most seriously disturbed land use patterns. Their soil N storage and mineralization rate were very low and exhibited significant variations, compared with other land use patterns. Lower net N mineralization rate correlated with lower N storage, and also, with lower fungi numbers. The N mineralization rate in disturbed forest soil which had recovered for several years was similar to that in primary forest soil, but decreased significantly when the forests were converted to agricultural land.