Internet of Things for the Future of Smart Agriculture: A Comprehensive Survey of Emerging Technologies

This paper presents a comprehensive review of emerging technologies for the internet of things(IoT)-based smart agriculture.We begin by summarizing the existing surveys and describing emergent technologies for the agricultural IoT,such as unmanned aerial vehicles,wireless technologies,open-source IoT platforms,software defined networking(SDN),network function virtualization(NFV)technologies,cloud/fog computing,and middleware platforms.We also provide a classification of IoT applications for smart agriculture into seven categories:including smart monitoring,smart water management,agrochemicals applications,disease management,smart harvesting,supply chain management,and smart agricultural practices.Moreover,we provide a taxonomy and a side-by-side comparison of the state-ofthe-art methods toward supply chain management based on the blockchain technology for agricultural IoTs.Furthermore,we present real projects that use most of the aforementioned technologies,which demonstrate their great performance in the field of smart agriculture.Finally,we highlight open research challenges and discuss possible future research directions for agricultural IoTs.     

土地当量经和复种指数的应用研究

当地当量比是耕作学中的重要概念，目前仅在间混作中初步应用，且不同教材看法不一。本文在分析间混作土地当量比应用现状的基础上，揭示了土地当量比的实质，对不同复种方式土地当量比的定义、计算公式及其应用进行了阐述，对土地当量比的意义进行了讨论。     

营养液低氧胁迫对网纹甜瓜幼苗生长和生理代谢影响

在水培条件下,研究了营养液低氧胁迫对网纹甜瓜幼苗生长指标、光合作用和生理代谢物质含量的影响。结果表明,低氧处理显著抑制了幼苗的生长,鲜重、干重等生长指标和叶绿素含量、净光合速率等光合指标均显著降低;低氧胁迫诱导幼苗不定根和根系活力显著增加;低氧胁迫下幼苗MDA、H2O2含量显著增加,但是幼苗体内可溶性糖、氨基酸、游离态多胺和热稳定蛋白含量也显著提高。与西域一号相比,星光生长较快,较高的光合速率、根系活力和生理代谢物质含量,缓解了低氧胁迫对幼苗的伤害。     

农田农情参数遥感监测进展及应用展望

农情参数是指反映作物生长过程及其产出的状态指标,关键农情参数主要包括作物长势、单产、物候和旱情等,可用于指导农田的生产管理。遥感是关键农情参数获取的有效手段,然而目前农情参数的遥感监测大多停留在大尺度、宏观监测的层面上,由于缺乏高时空分辨率、高准确度、低成本的农田信息获取技术,业务化的农田尺度农情参数获取受到了诸多因素的制约与限制。导致难以为农田生产管理提供及时的信息支持,这已经影响到精准耕作的发展与应用。文章在总结目前长势、单产、物候和旱情等几个主要农情参数遥感监测研究进展的基础上,分析了这些技术在农田尺度应用的瓶颈,并从新数据源和农情参数监测新模型两个角度出发,对农田尺度农情参数的获取进行了展望。     

Nanoporous Gold Catalyst for the Oxidative N-Dealkylation of Drug Molecules: A Method for Synthesis of N-Dealkylated Metabolites

A novel method for the selective catalytic N-dealkylation of drug molecules on a nanoporous gold (NPG) catalyst producing valuable N-dealkylated metabolites and intermediates is described. Drug metabolites are important chemical entities at every stage of drug discovery and development, from exploratory discovery to clinical development, providing the safety profiles and the ADME (adsorption, distribution, metabolism, and elimination) of new drug candidates. Synthesis was carried out in aqueous solution at 80 °C using air (oxygen source) as oxidant, in single step with good isolated yields. Different examples examined in this study showed that aerobic catalytic N-dealkylation of drug molecules on NPG has a broad scope supporting N-deethylation, N-deisopropylation and N-demethylation, converting either 3° amines to 2° amines, or 2° amines to 1° amines.     

The Use of Chemicals in Agriculture

This paper examines the use of agrochemicals in modern agriculture and horticulture. It begins by reflecting on the uncertainties of agricultural and horticultural production prior to the use of synthetic chemicals, then discusses the improved quantity and quality of output which is possible using agrochemicals. The social, environmental and agricultural hazards attendant upon chemical use are also considered. Provided that proper safeguards are observed, the use of agrochemicals is a sine qua non for the majority of farmers and growers in the UK.     

人尿中环丁甲羟氢吗啡及其代谢物的GC／MS分析研究

环丁尿羟氢啡阳性尿经酶解、醚洗、乙酸乙酯－异丙醇提取、衍生化后，用ＧＣ／ＭＳＤ进行分析，检出了环丁甲羟氢吗啡及其１种代谢物，方法灵敏简便。     

旱地农业降水高效利用技术应用研究

旱地农业建设必须借助科技进步，提高天然降水的有效利用，具体应围绕提高降水利用率和水分利用效率，在积极应用传统旱地农业技术的基础上，加强高新技术和常规技术相结合，重点推广雨水集蓄利用技术。     

Exploration of the land potential for the production of biomass for energy in the Netherlands

The energy potential for energy crops and biomass residues in the Netherlands is assessed. The analysis explores the possible use of land for biomass production in the future. Various government memorandums and analyses of the expected future land use in various sectors have served as the basis for the assessment of the supply of and the demand for land in the future. In this study the potential supply of agricultural land is based on expected productivity increments in agriculture and assumptions with respect to the future demand for agricultural products. Various future claims for infrastructure, forestry, urban areas and nature are subtracted from the expected supply. The net projected supply of land ranges from zero to 52 000 ha in 2000 to 110 000-250 000 ha in 2015. The supply of agricultural land depends however on a number of supra-national factors, such as the European agricultural policy, world market developments and the agricultural production in the countries in Eastern Europe. Uncertainties remain, therefore, and the projected supply of agricultural land should be considered as a possible scenario based on current trends. If the calculated land potential is used for energy crops like miscanthus and short rotation coppice, this land could contribute 0-10 PJ in 2000 and 27-59 PJ in 2015. Secondary biomass yields, such as those from forestry, agricultural residues, wood from prunings, etc., could contribute a further 34 PJ in 2000, decreasing to approximately 28 PJ in 2015. Taken together these potentials could satisfy 1-1.5% of the energy requirements of the Netherlands in 2000 and 1.5-2.5% in 2015, provided that energy farming is an economically feasible activity for farmers.     

Quality retention during the chilled distribution of farmed turbot (Psetta maxima): effect of a primary slurry ice treatment

The quality and shelf‐life of chilled farmed turbot (Psetta maxima) was evaluated by sensory, microbiological and biochemical procedures after being subjected to a two‐step refrigeration storage in slurry ice and flake ice, respectively. Turbot specimens were stored for 10 or 17 days in slurry ice, and then were transferred to flake ice for 1–3 days to simulate the sale conditions in the market. The results were compared with control batches stored only in flake ice and processed in parallel. Storage of turbot in the two‐step strategy resulted in a better maintenance of sensory quality, especially with regard to its mucus production and gill odour development, better control of microbial activity, especially of aerobes, and the slowing down of some biochemical degradation mechanisms such as the nucleotide degradation pathway and trimethylamine production. As a consequence, the shelf‐life was extended significantly. From these results it can be concluded that the refrigerated transport of farmed turbot in slurry ice enhances its shelf‐life, before its transfer into flake ice in the retail market.