Chalcogen heteroatoms doped nickel-nitrogen-carbon single-atom catalysts with asymmetric coordination for efficient electrochemical CO_(2) reduction

The electronic configuration of central metal atoms in single-atom catalysts(SACs)is pivotal in electrochemical CO_(2) reduction reaction(eCO_(2)RR).Herein,chalcogen heteroatoms(e.g.,S,Se,and Te)were incorporated into the symmetric nickel-nitrogen-carbon(Ni-N_(4)-C)configuration to obtain Ni-X-N_(3)-C(X:S,Se,and Te)SACs with asymmetric coordination presented for central Ni atoms.Among these obtained Ni-X-N_(3)-C(X:S,Se,and Te)SACs,Ni-Se-N_(3)-C exhibited superior eCO_(2)RR activity,with CO selectivity reaching~98% at-0.70 V versus reversible hydrogen electrode(RHE).The Zn-CO_(2) battery integrated with Ni-Se-N_(3)-C as cathode and Zn foil as anode achieved a peak power density of 1.82 mW cm^(-2) and maintained remarkable rechargeable stability over 20 h.In-situ spectral investigations and theoretical calculations demonstrated that the chalcogen heteroatoms doped into the Ni-N_(4)-C configuration would break coordination symmetry and trigger charge redistribution,and then regulate the intermediate behaviors and thermodynamic reaction pathways for eCO_(2)RR.Especially,for Ni-Se-N_(3)-C,the introduced Se atoms could significantly raise the d-band center of central Ni atoms and thus remarkably lower the energy barrier for the rate-determining step of ^(*)COOH formation,contributing to the promising eCO_(2)RR performance for high selectivity CO production by competing with hydrogen evolution reaction.

Influence of Diversity of Prototypical Ethnic Culture in Diversity of Glutinous Rice in Southeast of Guizhou

There were quite abundant prototypical ethnic cultures and plant diversity in Qiandongnan （ Southeast of Guizhou） ,where the primitive natural ecology was also perfectly conserved. It was honored by World Native Culture Fund as One of the Eighteen Ecological and Cultural Conservations in the World. The prototypical ethnic culture of Southeast of Guizhou, as a stable life-style and economic culture type of the local people, came into being in the process of the local minorities＇ communicating, blending and struggling against the natural environment in the long course of history. It could be seen from this research that there were our preliminary research that there are quite abundant resources in Southeast of Guizhou in terms of prototypical ethnic cultures and genetic diversity of glutinous rice. A full reflection of the culture of Glutinous Rice could be seen in the local minority people＇s daily life, production, custom, religious belief, etc. These showed that the formation and great vitality of the genetic diversity of glutinous rice was not only determined by the diversity of local prototypical ethnic cultures but also to its own biotic condition and its adaptation to natural ecology. It was showed that prototypical ethnic cultures had positive impact on the conservation and utilization of Glutinous Rice diversity.

Primary Succession of Algal Community Structure in Desert Soil

The microbiotic crust study is among new focuses in investigating on the desertification control. Based on determination of algal crusts with different successive ages (4-, 8-, 17-, 34-, 42-year-old) and unconsolidated sand in the desert area, species composition and clustering analyses were carried out in this study. Results on successional orientation revealed that (1) the abundance of Cyanophyta, specially of Scytonema javanicum gradually decreased; (2) the abundance of Chlorophyta, Bacillariophyta and a species of Cyanophyta, Phormidium tenue increased; (3) the biodiversity increased gradually with the community succession; and (4) biomass of microalgae increased at the early stage, but decreased at the later stage due to the abundance of lichens and mosses. But, the speed of natural succession was so slow that the community-building species was still the first dominant species after 42 years, except that its dominant degree decreased just slightly. However, successive speed and trend were affected by water, vegetation coverage, terrain, time and soil physico-chemical properties as well, especially Mn content in the soil appeared to have a threshold effect.

Effects of Grassland Eco-Protection Compensation and Reward System

Grassland ecological protection compensation and reward policy is the largest-scale investment concerning themost extensive areas since foundation of the PRC. It will be the long-term implementationpolicy for grassland ecological protection. In this study,based on macro-perspective, the policy effects ofgrasslandproductivity, ecological protection, animal husbandryoutput, pastoralists＇ income were ana- lyzed. The resultsshow that, afterimplementation of the policy, naturalgrass production and grasslandtheoretical stocking rateincreased. The averagenatural grasslandlivestockoverloading ratedecreased significantly, comprehensivenationalgrasslandvegetation coverageis increasing. Besides, adult cattleandbeef yield arefluctuated. Sheep head, adult sheep, sheep production, milk productionincreasedin varying degrees. The per capita netincomeof farmers and pastoralists, livestock income, the proportion oflivestockincomewere higher than those beforeimplementation of the policy.

Transformation of Metallothionein Gene into Mushroom Protoplasts by Application of Electroporation

Metallothionein gene (MT) has been transferred into mushroom protoplasts by electroporation. It is a low molecular weight, cysteine-rich and metal-binding protein. MT can bind metals. Its synthesis is induced by Zn ion. Thus the expression of MT gene in mushroom can improve the accumulation of Zn in this fungus. This transgenic mushroom, consumed as a kind of vegetable, can supply the necessary Zn to people who are short of the element. When protoplasts were prepared, the concentration (C) of protoplasts is 6.745 x 10(6) /mL. After protoplast electroporation, the transformation rate of protoplasts is 0.01 %. Polymerase chain reaction (PCR) analysis showed that the gene had been integrated into the mushroom chromosome, SDS-PAGE, Western blot analysis indicated that the MT gene had been expressed in the transgenic mushroom. The expressing level, detected by ELISA, is 0.6 % - 0.8 %. Tested for metal resistance, the wild-type mushroom growth was inhibited on die medium containing 1.0 - 1.2 mmoL/L ZnSO4. While the transgenic mushroom was inhibited on the medium containing 1. 5 - 2.0 mmol/L ZnSO4. The mycelium can develop into hymenophore in the medium of rice bran: sawdust = 1: 3, and not in the medium of rice bran: sawdust = 1: 4.

No C_4 Plants Found at the Haibei Alpine Meadow Ecosystem Research Station in Qinghai, China: Evidence from Stable Carbon Isotope Studies

Using the measurement of stable carbon isotopes in leaves as a tool to investigate photosynthetic pathway of 102 plant species grown at an alpine meadow ecosystem, at the foot of the Qilian Mountain, Qinghai, China. The results indicate that the delta C-13 values of plants have a narrow range from -28.24parts per thousand to -24.84parts per thousand, which means that none of the species examined belongs to C-4 and crassulaceous acid metabolism (CAM) photosynthetic pathway and all of these species perform photosynthesis through the C-3 pathway. This is likely due to a long-term adaptation to environments at the alpine meadow ecosystem.

Research Progress of Vulnerability Assessment on Grassland Ecosystem under Climate Change

[Objective] The aim was to review on vulnerability evaluation of grassland ecosystem under climate change.[Method] In the research,vulnerability evaluation methods of ecosystem under climate changes,at home and abroad,and the related cases and research progress in China were reviewed.In addition,the future of evaluation research was predicted.[Result] Ecosystem vulnerability to climate change is an important part of climate change research.It is necessary and urgent to improve evaluation methods and reduce uncertainty of future vulnerability evaluation to make evaluation more comprehensive and objective.Furthermore,evaluation on effects of human activity on natural ecosystem vulnerability should be highlighted.[Conclusion] The research provided reference for establishment of a new management model for ecosystem adaptability to climate and sustainable development of grasslands in northern China.

Advances in Grassland Ecosystem Research in Northern Tibetan Plateau

With the aggravation of global change, the response and adaptation of the unique ecosystem in Qinghai-Tibet Plateau to global change have been increasingly concerned by scientific community day by day, which makes the sensitivity and fragility of this ecosystem in response to global change widely recognized by scholars. On the basis of introducing the present research process on the degenerate mechanisim, measures of and approaches to recovery, carbon cycle and primary productivity toward global change, we put forward several propositions on studying the alpine grassland ecosystem in Northern Tibetan Plateau.

Flow Cytometric Evidence for Hydroxyl Radical-induced Apoptosis in Tobacco Protoplasts

Protoplasts prepared from tobacco (Nicotiana tabacum L., cultivar BY-2) suspension cells have similar morphological characteristics to those in animal cells. The hallmarks of apoptosis such as condensation and peripheral distribution of nuclei, TUNEL positive reaction, and DNA ladders were observed when tobacco protoplasts were treated with the hydroxyl radical generating system (1.0 mmol/L FeSO4/0.5 mmol/L H2O2). In animals, the loss of transmembrane potential (DeltaPsi(m)) and the exposure of phospholipid phosphatidylserine (PS) are believed to be the main apoptosis events. To test whether these significant processes take place in plants, flow cytometry was used to detect annexin V binding and changes in DeltaPsi(m). Results showed that the PS turned out from inner membrane and DeltaPsi(m) gradually decreased during the apoptosis. All these apoptotic characteristics proved that hydroxyl radicals can cause typical programmed cell death (PCD) in tobacco protoplasts and this design can be served as an effective experiment system to explore the mechanism of plant apoptosis.

Evaluation on Service Function of Plain Forest Ecosystem in Northwest China

[Objective] The paper aimed to evaluate the plain forestry＇ service function in Northwest China.[Method] Based on general and representative investigations with county used as the minimum unit,evaluation on service function of plain forestry ecosystem in Northwest China was carried out by measuring the quality and quantity.[Result] In 2005,the plain forestry in Northwest China plays a profound role in water and soil conversation,carbon sequestration by vegetation and soil,oxygen release by plants,sulfur dioxide absorption and and so on.[Conclusion] This paper laid foundation for research on service function of plain forest ecosystem in Northwest China.

Investigation of electrostriction appliance and its applicationfor bionics flapping aircraft

A novel design for an electrostriction appliance derived from the theory and application of electromagnetics is presented. The working principle, that is the application of gravitation and elasticity together to realize the ＂shrinking＂ and ＂extending＂ effect from the distortion and transforming power into mechanical energy, is briefly explained. The characteristic parameter relationships are established and the experimental research is performed. Experimental results show that this sort of electrostriction appliance can perform well as regards driving force and beeline displacement, and furthermore, its self-weight is smaller. This makes it suitable for beeline drivers with a high application value, especially for the driver of the bionic appliance. In the application of the electrostriction appliance to a bionics-flapping aircraft, the wings can work with a flapping angle in the range of a certain value by controlling the ＂shrinking＂ and ＂extending＂ of the electrostriction appliance. It can reduce the startup power and the impact load of the driver. The flapping extent of the wings will change when the voltage which is put into the electrostriction appliance varies. This makes it more flexible as the bionics-flapping aircraft realizes different actions of flying.

The Influence of Plant Diversity and Functional Composition on Ecosystem Stability of Four Stipa Communities in the Inner Mongolia Plateau

The main purpose of this study was to examine the effects of plant species diversity and functional composition (the identity of the plant functional groups) on ecosystem stability of Stipa, communities in the Inner Mongolia Plateau. The research work was based on a 12-year study (from 1984 to 1995) of species abundance, diversity, and primary productivity of four Stipa communities, i.e. S. baicalensis Roshev., S. grandis P. Smirn., S, krylovii Roshev., and S. klemenzii Roshev. respectively. The Shnnon-Wiener index was used as a measurement of plant diversity, while functional composition was used to differentiate the functional groups that were included in the communities. The plant species of four Stipa communities were classified into functional groups based on the differences in life forms and ecological groups, which influence their performance in resource requirements, seasonality of growth, tolerance to water stress, and life history. Plant species were classified into five functional groups based on their differences in life form, shrubs and half shrubs, perennial bunch grasses, perennial rhizome grasses, forbs, annuals and biennials. Based on their differences in water requirement these species were classified into four functional groups: xerads, intermediate xerads, intermediate mesophytes, and mesophytes. The results showed: 1) Plant species diversity stabilized ecosystem processes. Shannon-Wiener index were 2.401 4, 2.172 0, 1.624 8, 0.354 3 from S. baicalensis community to S. grandis, S. krylovii and S. klemenzii community, respectively. The dynamics of the aboveground net primary productivity (ANPP) for a 12-year's period showed a reverse pattern, the coefficients of variation of the four communities were 21.94%, 20.63%, 29.21% and 39.72% respectively. 2) The Life form functional group component of diversity was a greater determinant of the ecosystem processes than the species component of diversity. The effects of perennial bunch grasses, perennial rhizome grasses and forbs on community stability were highly significant. 3) The ecological group component of diversity was also a great determinant of the ecosystem processes. The effects of xerads, intermediate xerads, and mesophytes on community stability were also very strong.

Contributions of Chinese Botanists to Plant Tissue Culture in the 20th entury

This paper looks back to the development of plant tissue culture in China in the last century. Since 1934, tissue culture studies in China has kept up with the international development in the fields. Progress has been made by Chinese in nearly every branches of tissue culture, including in vitro organogenesis, shoot tip culture, anther culture, ovary culture, endosperm culture, protoplast culture as well as mass cell culture. On the basis of reviewing the articles written by Chinese on plant tissue culture, the internationally recognized contributions are specially mentioned. The applications of plant tissue culture to agriculture and industry in China are also introduced.

Appropriate Garden Design of Primitive Ecology Based on the Indigenization of Environmental Ethics

The accelerating urbanization process leads to aggravated environmental problems, thus garden design which is a creative activity connecting human and nature has attracted much attention, and also garden designers have had to rethink about environmental ethics and morals. This study, from the perspective of environmental ethics, duly proposed the brand-new concept of 'appropriate garden of primitive ecology', proceeded from the orientation, form, value, theoretical basis, realistic significance, culture and consumption psychology of 'garden of primitive ecology', fully developed outstanding ecological wisdoms and morals in traditional Chinese garden culture, boosted garden designs to the environmental ethics level of eco-justice, to seek for the approach to 'garden of primitive ecology' with indigenous Chinese environmental ethic characteristics.

Culture of Embryonic Stem Cell by Primordial Germ Cells of Down Producing Goat

[Objective] The paper was to establish embryonic stem cell system of goats. [Method] Numerous primordial germ cell colonies were derived from gonadal ridge and the surrounding tissues in 20 millimeter fetuses of down producing goat. Primordial germ cells and goats embryonic fibroblasts obtained from conceptus of equivaient gestational age were co-cultured. [Result] The colonies showed some characteristics of embryonic stem cells, such as the morphology of nest-like, they continued to be AKP positive and the ability to be continuously passed [Conclusion] These cells were pluripotent and ES-like cells.

Mechanism of microcystin removal from eutrophicated source water by aquatic vegetable bed

For purifying raw water for tap water treatment, the aquatic vegetable bed （AVB） experiment has been carded out in a hypertrophic waterfront of Taihu Lake, China. The average removal rates of total microcystin-RR and microcystin-LR are 63.0% and 66. 7%, respectively. Experiments indicate that lpomoea aquatica can absorb microcystin by using enzyme-linked immunosorbent assay （ELISA）, and the roots absorb more toxins than leaves and stems. Fluorescence in situ hybridization （FISH） is used to analyze the density of microcystin degrading bacteria in the AVB sediment. Two species of microcystin degrading bacteria are detected, which indicate that microcystin bio-degradation process happened in the AVB. Protozoa and metazoa are abundant in root spheres. Aspidisca sp., Vorticella sp., Philodina sp., and Lecane sp. are dominant species. The predation functions of protozoa and metazoa have a positive effect on the removal of cyanobacteria and microcystin.

Research process of the calcium signaling in cyanobacteria

The potential involvement of calcium in signalling in cyanobacteria has been investigated in recent years. Enough evidences showed that the cyanobacteria were capable of sensing and distinguishing different environmental stimuli, and making responses in ways of Ca^2＋ transients, which were the results of influx or efflux of Ca^2＋ aroused by different environmental stimuli. The calcium signal elicited by nitrogen starvation was crucial to heterocyst differentiation in filamentous cyanobacteria Anabaena species. Identification of a calcium-binding protein （CcbP） from Anabaena sp. PCC 7120 provided further evidence, and the degradation and down-regulation of CcbP accounted for the generation of calcium signal when nitrogen starvation exits. However, the encoding and decoding mechanisms of the calcium signals in cyanobacteria still remain unclear. In order to reveal the exact role of it, a detailed, systematic investigation will be needed, especially for the calcium dynamics at the single cell level.

A New Model on Origin and Evolution of Biology

Modified classical Boltzmann entropy as generalized entropy, then proposed Maximum Generalized Entropy Principle fusing physics and biology, and established a new model for biological origin and evolutions based on this principle, finally took protein evolution for an example to analyze. The model provided some reference for biological complexity research.

Progress in Research on Intercellular Movement of Protoplasm in Higher Plants

Since nuclear extrusion was rediscovered in young Allium scale by S.H.WU in the years of 1950's systematic investigations on this phenomenon were carried out with various kinds of microscopic techniques and plant materials to collect more effective evidence to clarify the debate about whether the nuclear extrusion is an artifact or normal event. In the cooperative research of S. H. WU and C. H. LOU the normality of the occurrence of nuclear extrusion either in growing part of plant or in senescent tissue has been confirmed. This event is intimately associated with the physiological state of the tissues/cells and may play an important role in redistribution and reutilization of cell contents. Based on the results obtained a hypothesis of intercellular movement of protoplasm as a means of translocation of organic material in plants was suggested. Chromatin extrusion was also discovered in the pollen mother cells (cytomixis) of certain angiosperms by G. C. ZHENG and his team. Intercellular migration of chromatin appears most frequently at the stage of synizesis. Cytomixis has been studied in relation to variation and evolution. Chromosome aberration has been considered to be closely associated with chromatin extrusion. By vital microscopic observations of the live tissues of garlic (Allium sativum L.) bud and wheat (Triticum aestivum L.) ovule combined with cinemicroscopy and video recording it has been uncovered that, not only the nuclear material but also the cytoplasm could traverse the intercellular channels by vigorous contraction and expansion, and they may simultaneously extrude out of a cell but often asynchronously migrate from one cell to another. The involvement of cytoplasmic constituents in intercellular migration was also detected in pollen mother cells with electron microscopy. Regarding the mechanism of intercellular movement a series of experiments provide convincing evidence showing that this kind of movement is an active metabolic process closely coupled with energy metabolism, and the motive power for driving the extrusion may be supplied by the contractile proteins in protoplasm.