Research Plan on the Strategic Development of High-value Eco-agriculture in the Middle-lower Reaches of Yangtze River

At present,high-value eco-agriculture research in China is till limited and controversial,theoretical innovation and practices on eco-agriculture should be conducted.The key problems which should be solved urgently on the development of high-value eco-agriculture in the middle-lower reaches of Yangtze River now including：the connotation and characteristics of high-value eco-agriculture,the construction of high-value eco-agriculture system and the policies of the development of high-value eco-agriculture.Therefore,the strategic development research on high-value eco-agriculture mainly includes the following aspects：development of agriculture modernization and theory and practices of eco-economics;theory of high-value eco-agriculture;practice of high-value eco-agriculture in the middle-lower reaches of Yangtze River;construction of high-value eco-agriculture in the middle-lower reaches of Yangtze River;development strategy and system innovation of high-value eco-agriculture in the lower and medium reaches of Yangtze River.

Study on Regionalization of High Efficiency Eco-agriculture in Eco-economic Zone of Poyang Lake

The high efficient eco-agricultural zone in Eco-economic Region of Poyang Lake was divided into three different areas. 12 indicators including per capita cultivated land,forest coverage,comprehensive utilization rate of straw,the ratio of the effective irrigation area to the arable land,amount of pesticide usage per unit area of arable land,the output value ratio of planting industry,the output value ratio of forestry and fruit industry,the output value ratio of stock farming,the output value ratio of fishery,the proportion of sown area of crop,proportion of sown area of oil plants and the proportion of sown area of vegetable were screened to construct the indicator system of regionalization of high efficient eco-agriculture. The average index values of the high efficient eco-agricultural regionalization of three regions were obtained,the development direction of the efficient eco-agriculture construction of three areas were analyzed according to the natural resources characteristics f eco-agricultural and requirements of high efficient eco-agricultural development of the regions.

Development mode of the E-commerce of eco-agriculture products in China

With the extensive use of the Internet and mobile technology, E-commerce in China has shown tremendous growth advantages and market potential, especially in promoting the access of eco-agriculture products. The E-commerce of agriculture products has shown diversification on the mainstay. "Three products, one indication"(pollution-free, green product, organic product, geographical indication) has becomes the primary character. Although the market of fresh products occupies a limited and meager profit, the blue sea effect has caused capital to enter into a large-scale development. It is very clearly shown after the analysis that the market of eco-agricultural E-commerce is vast and the expansionist policy for E-commerce environment is favorable. Meanwhile the required hardware and software of network in E-commerce are basically equipped with rapid development of service technology and strong driving force for innovation and development as well as an endless stream of new models and platforms. The whole phrase of development can be divided into five major stages. Through the analysis of five perspectives, such as platform, driver, participant, food supplier and Taobao, 16 types of agro-products E-commerce models and their different types of e-payment support systems are summarized, revealing the two major bottlenecks of development, namely the markets with limited share and low profit-making and the impact of cold chain services on E-commerce development. The thesis finally fortells the ten trends for the future development.

Broadband high-efficiency dielectric metalenses based on quasi-continuous nanostrips

Benefiting from the abrupt phase changes within subwavelength thicknesses,metasurfaces have been widely applied for lightweight and compact optical systems.Simultaneous broadband and high-efficiency characteristics are highly attractive for the practical implementation of metasurfaces.However,current metasurface devices mostly adopt discrete micro/nano structures,which rarely realize both merits simultaneously.In this paper,dielectric metasurfaces composed of quasi-continuous nanostrips are proposed to overcome this limitation.Via quasi-continuous nanostrips metasurface,a normal focusing metalens and a superoscillatory lens overcoming the diffraction limit are designed and experimentally demonstrated.The quasi-continuous metadevices can operate in a broadband wavelength ranging from 450 nm to 1000nm and keep a high power efficiency.The average efficiency of the fabricated metalens reaches 54.24%,showing a significant improvement compared to the previously reported metalenses with the same thickness.The proposed methodology can be easily extended to design other metadevices with the advantages of broadband and high-efficiency in practical optical systems.

Research on industrialization of eco-agriculture:theoretical framework and the case of Yunnan,China

The industrialization of eco-agriculture has applied modern science technology in accordance with ecological principles and has promoted agricultural production.As a subsystem of agricultural industrial clusters,the industrialization of eco-agriculture is the specific applications of cluster concept in the industrialization of eco-agriculture development.Industrialization of eco-agriculture cluster will achieve eco-agriculture and interact with industrial cluster which forms eco-agriculture integration and composite industry and ultimately realize the new benign circulation eco-agriculture model.According to the ecological engineering basic principles of recycling of the overall coordination,industrialization of eco-agriculture is focusing on the main systems operating coordination between the various subsystems and its various factors,and will maintain a reasonable ecological and economic structure to ensure the recycling of natural resources.Industrialization of eco-agriculture in Yunnan has adjusted the agricultural production structure to keep the stability of the gross grain production and economic development and has taken effective measures to vigorously improve land use and land productivity.Various ways of improving soil fertility has vigorously promoted other water-saving agricultural technologies.Ecological protection of rice no-tillage,cultivation of crop cultivation of the integrated control crop disease pests grass and agricultural production have taken the sustainable development.

High-efficiency Carbonation Modification Methods of Recycled Coarse Aggregates

To solve the problem of only surface carbonation and realize high-efficiency carbonation of recycled coarse aggregate,the method of carbonated recycled coarse aggregate with nano materials pre-soaking was first put forward.The carbonation effect of modified recycled coarse aggregate with three different carbonation methods was evaluated,and water absorption,apparent density and crush index of modified recycled coarse aggregate were measured.Combined with XRD,SEM,and MIP microscopic analysis,the high-efficiency carbonation strengthening mechanism of modified recycled coarse aggregate was revealed.The experimental results show that,compared with the non-carbonated recycled coarse aggregate,the physical and microscopic properties of carbonated recycled coarse aggregate are improved.The method of carbonation with nano-SiO_(2) pre-soaking can realize the high-efficiency carbonation of recycled coarse aggregate,for modified recycled coarse aggregate with the method,water absorption is reduced by 23.03%,porosity is reduced by 44.06%,and the average pore diameter is 21.82 nm.The high-efficiency carbonation strengthening mechanism show that the pre-socked nano-SiO_(2) is bound to the hydration product Ca(OH)_(2) of the old mortar with nano-scale C-S-H,which can improve the CO_(2) absorption rate,accelerate the carbonation reaction,generate more stable CaCO_(3) and nano-scale silica gel,and bond to the dense three-dimensional network structure to realize the bidirectional enhancement of nano-materials and pressurized carbonation.It is concluded that the method of carbonation with nano-SiO_(2) pre-soaking is a novel high-efficiency carbonation modification of recycled coarse aggregate.

The Unified Concept of Eco-agricultural Tourism

The origination of 'eco-agricultural tourism' concept is introduced,similar concepts are discriminated,and a unified concept is suggested with proper reasons.

High-efficiency Planting Techniques of Five Crops a Year for Fresh Edible "Faba Bean/Spring Mazie+Soybean-Autumn Maize/Autumn Soybean"

The high-efficiency planting mode for five crops a year of fresh edible ＂faba bean/spring maize＋soybean-autumn maize/autumn soybean＂ was introduced, and its yield and economic benefits were compared with the planting mode of three crops a year of ＂faba bean-spring maize/red bean＂. The results showed that the planting method for fresh edible ＂faba bean/spring maize＋soybean-autumn maize/autumn soybean＂ was much easier to operate with the input-output ratio of about185.6%, and its yield and economic benefits were 2.09 and 1.83 times of that of the planting mode for three crops a year, significantly improving the agricultural yield and income of farmers. In addition, the cropping index of the planting mode for fresh edible fresh edible ＂faba bean/spring maize ＋soybean-autumn maize/autumn soybean＂ reached up to 350%, and planting faba bean once a year and soybean twice a year could make the biological fixation amount of nitrogen increase 350-450kg/m^2, which equaled to up to 700 kg/m^2 of urea, showing significant ecological and social benefits. Based on the comparison results, the high-yield culture techniques of the planting mode of fresh edible ＂faba bean/spring maize＋soybean-autumn maize/autumn soybean＂ were summarized.

Strength and Weakness of Eco-agricultural Sightseeing Development in Baise City and Corresponding Strategies

The development of eco-agricultural sightseeing in Baise City shows a sound foundation and outstanding advantages as well as a rapid growth trend in recent years, however, there are also problems to be settled, such as shortage of talents, insufficient planning, low level of development, limited products and lack of competitive products. In view of such a condition, development concepts should be reformed first, competitive and special products made, marketing and propaganda enhanced to promote the healthy, coordinated and ordered development of eco-agricultural sightseeing in Baise City, Guangxi Zhuang Nationality Autonomous Region.

SWOT Analysis of Eco-agricultural Tourism Development in Zhenjiang City,Zhejiang Province of China

Concept and significance of eco-agricultural tourism was introduced, SWOT Analysis was applied to analyze strengths, weaknesses, opportunities and threats of eco-agricultural tourism development in Zhenjiang. Its strengths were concluded as excellent natural conditions, diversified species, abundant eco-agricultural tourism resources, advantageous location; weaknesses as low development level, serious homogeneity of products, low technical level of peasants, lack of management staff and technician, seriously degraded eco-environment; opportunities as preferential policies, joint development of "Ningbo-Zhenjiang-Yangzhou" Tourist Zone; threats as backward concepts and non-standard management order. Through fully analyzing development strategies of its eco-agricultural tourism, it was stressed that present industrial structure should be adjusted, environment protected; scientific planning, functional division and government supervision enhanced; combined advantages of natural resources integrated to promote the sustainable development of agro-tourism; eco-agricultural resources well planned, new ideas introduced in the design of tourist products.

Construction of Eco-agricultural Tourist Product Mode from the Perspective of Circular Economy

Concepts and connotations of circular economy and eco-agricultural tourism were introduced,and feasibility of applying circular economy in eco-agricultural tourism was further studied.It was stressed that development of eco-agricultural tourism complies with the theme of resource recycling,moreover,both eco-agricultural tourist products and circular economy value environment protection,and target at the win-win of ecological and economic benefits.From the perspective of circular economy,the construction of eco-agricultural tourist product mode was studied,construction of eco-agricultural tourist areas,catering and accommodation areas and traffic construction of eco-agricultural scenic areas were discussed.The study stressed that connotations of circular economy can be used to restrain eco-agricultural tourism,and realize recycling and sustainable development of resources.

Study on Planning and Design Mode of Eco-agricultural Demonstration Base in Poyang Lake Eco-economic Zone

Guided by the Planning of Poyang Lake Eco-economic Zone, traffic and geographic conditions of the Eco-agricultural Demonstration Base in the study area were analyzed, and design principles proposed as "adaptation to local conditions, scientific planning, benign circulation and sustainable development". Detailed planning and design was interpreted from the perspectives of infrastructure planning and functional area planning. Specifically, infrastructure construction should focus on traffic design, water, power and gas supply design, and also architectural design; while functional areas should be gradually developed from south section to central and then north section. It was to establish a design and planning mode that can be widely applied.

Adiabatic cooling for cold polar molecules on a chip using a controllable high-efficiency electrostatic surface trap

We propose a controllable high-efficiency electrostatic surface trap for cold polar molecules on a chip by using two insulator-embedded charged rings and a grounded conductor plate. We calculate Stark energy structure pattern of ND3 molecules in an external electric field using the method of matrix diagonalization. We analyze how the voltages that are applied to the ring electrodes affect the depth of the efficient well and the controllability of the distance between the trap center and the surface of the chip. To obtain a better understanding, we simulate the dynamical loading and trapping processes of ND3 molecules in a ｜J, KM = ｜1,-1 state by using classical Monte–Carlo method. Our study shows that the loading efficiency of our trap can reach ～ 88%. Finally, we study the adiabatic cooling of cold molecules in our surface trap by linearly lowering the potential-well depth（i.e., lowering the trapping voltage）, and find that the temperature of the trapped ND3 molecules can be adiabatically cooled from 34.5 m K to ～ 5.8 m K when the trapping voltage is reduced from-35 k V to-3 k V.

INVESTIGATION OF SURFACE TEMPERATURE IN HIGH-EFFICIENCY DEEP GRINDING

A new thermal model with triangular heat flux distribution is given in high-efficiency deep grinding. The mathematical expressions are driven to calculate the surface temperature. The transient behavior of the maximum temperature on contact area is investigated in different grinding conditions with a J-type thermocouple. The maximum contact temperatures measured in different conditions are found to be between 1 000 ℃ and 1 500 ℃ in burn-out conditions. The experiment results show good agreement with the new thermal model.

High-Efficiency Mid-Infrared Picosecond MgO:PPLN Single Resonant Optical Parametric Oscillator

We demonstrate a high-emciency mid-infrared picosecond optical parametric oscillator （OPO） based on MgO doped periodically poled lithium niobate （MgO：PPLN） with a laser diode array （LDA） pumped Innoslab amplifier as the pumping source. Under a 16 W synchronously pumping power, 4.5 W of idler light at 2896nm is obtained. A tuning range of idler light from 2688nm to 3016nm is achieved, within which the highest optical-optical conversion ettlciency from pump power to OPO output is 35.1%. Moreover, a signal light of -500mW from 1644 to 1700nm with a repetition rate of 233.8 MHz is generated.

Effect of Structural Parameters on the Performance of NS High-efficiency Composite TraysⅠ.The Effect of Aperture and Opening Ratio on NS High-efficiency Composite Trays

In this paper,the structure and characteristics of the NS high-efficiency composite trays based on the doublelayer aperture jet sieve plate and compositely structured packing were investigated.The effect of aperture and opening ratio of plate on the fluid dynamics of the NS high-efficiency composite trays,such as the dry tray pressure drop,the wet tray pressure drop,the entrainment,the froth height,the leakage and mass transfer characteristics,were investigated.As a result, the low pressure drop,the high efficiency and the high capacity are the main advantages of the NS high-efficiency composite trays compared to other types of trays.According to this study,small aperture is useful for reducing the pressure drop and entrainment with a high mass transfer efficiency;while large aperture can achieve high capacity and efficiency in a broader operating range at the same pressure drop and entrainment.

Toward high-efficiency perovskite solar cells with one-dimensional oriented nanostructured electron transport materials

The unique advantages of one-dimensional(1D)oriented nanostructures in light-trapping and chargetransport make them competitive candidates in photovoltaic(PV)devices.Since the emergence of perovskite solar cells(PSCs),1D nanostructured electron transport materials(ETMs)have drawn tremendous interest.However,the power conversion efficiencies(PCEs)of these devices have always significantly lagged behind their mesoscopic and planar counterparts.High-efficiency PSCs with 1D ETMs showing efficiency over 22%were just realized in the most recent studies.It yet lacks a comprehensive review covering the development of 1D ETMs and their application in PSCs.We hence timely summarize the advances in 1D ETMs-based solar cells,emphasizing on the fundamental and optimization issues of charge separation and collection ability,and their influence on PV performance.After sketching the classification and requirements for high-efficiency 1D nanostructured solar cells,we highlight the applicability of 1D TiO_(2)nanostructures in PSCs,including nanotubes,nanorods,nanocones,and nanopyramids,and carefully analyze how the electrostatic field affects cell performance.Other kinds of oriented nanostructures,e.g.,ZnO and SnO_(2)ETMs,are also described.Finally,we discuss the challenges and propose some potential strategies to further boost device performance.This review provides a broad range of valuable work in this fast-developing field,which we hope will stimulate research enthusiasm to push PSCs to an unprecedented level.

Developing high-efficiency base editors by combining optimized synergistic core components with new types of nuclear localization signal peptide

The clustered regularly interspaced short palindromic repeats(CRISPR)–CRISPR-associated protein(Cas) system has been widely used for genome editing. In this system, the cytosine base editor(CBE) and adenine base editor(ABE) allow generating precise and irreversible base mutations in a programmable manner and have been used in many different types of cells and organisms. However, their applications are limited by low editing efficiency at certain genomic target sites or at specific target cytosine(C) or adenine(A) residues. Using a strategy of combining optimized synergistic core components, we developed a new multiplex super-assembled ABE(sABE) in rice that showed higher base-editing efficiency than previously developed ABEs. We also designed a new type of nuclear localization signal(NLS) comprising a FLAG epitope tag with four copies of a codon-optimized NLS(F4NLS^(r2)) to generate another ABE named F4NLS-sABE. This new NLS increased editing efficiency or edited additional A at several target sites. A new multiplex super-assembled CBE(sCBE) and F4NLS^(r2) involved F4NLS-sCBE were also created using the same strategy. F4NLS-sCBE was proven to be much more efficient than sCBE in rice. These optimized base editors will serve as powerful genome-editing tools for basic research or molecular breeding in rice and will provide a reference for the development of superior editing tools for other plants or animals.

Approaches for High-Efficiency III-V/Si Tandem Solar Cells

The Si tandem solar cells are very attractive for realizing high efficiency and low cost. This paper overviews current status of III-V/Si tandem solar cells including our results. The analytical results for efficiency potential of Si tandem solar cells and loss analysis of Si bottom cells as well as bandgap energy optimization of sub-cells are presented. The 2-junction and 3-junction Si tandem solar cells have potential efficiencies of 36% and 42%, respectively. ERE (external radiative efficiency) analysis for Si solar cells is analyzed in order to clarify properties of Si bottom solar cells. Properties of single-crystalline Si heterojunction solar cell fabricated in this study were analyzed. The current status of efficiencies of our Si bottom cell, upper III-V 2-junction solar cell and III-V/Si 3-junction tandem solar cell was shown to be 5.2% and 28.6% and 33.8%. Achievement of Jsc of 12 mA/cm2 for Si bottom cell is necessary to realize high-efficiency 3-junction Si tandem solar cells with an efficiency of more than 37%. In addition, this paper presents ERE analysis of III-V 2-junction upper solar cells for improving III-V/Si 3-junction tandem solar cells. Several ways to improve efficiency of III-V/Si 3-junction tandem solar cells by reducing non-radiative recombination, optical and resistance losses are shown.