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Dendrobium is the second largest genus of Orchidaceae, distributed in southern and southwestern China. The number of Dendrobium is large, but some taxa have not been discovered. During the investigation of orchid resources in Xizang, two Dendrobium species were discovered, which were identified as D. macraei Lindl. and D. ritaeanum King & Pantl. Both were recorded for the first time in China. The results are as follows: D. macraei is similar to D. plicatile, with the difference that the edge of the middle lobe of lip is entire, apex concave; D. ritaeanum is similar to D. angustifolium, the flowers of the former are very small, and sepals and petals do not have purple stripes, and the lip is triangular up to 1.4 cm in length. The detailed morphological characteristics and photographs of the two species are provided. The specimens are stored in the Herbarium of Xizang Agricultural and Animal Husbandry University. This discovery enriches the local data and the potential medicinal plant resource reserve of orchids in China, and is of great significance to the biodiversity study of orchids and the investigation of medicinal orchid resources.

The application of digital twin technology in the field of intelligent mining needs to face many complex and special technological breakthroughs. This article elaborates on the applicability of digital twins in the field of intelligent mining, and summarizes the research and application status of digital twin technology in coal mine safety, production, and operation management. In terms of coal mine safety management, digital twin technology is mainly applied in disaster warning, risk control, disaster rescue, etc. In terms of coal mine production, digital twin technology is mainly applied in the overall mining working face area, monitoring and control of single machine mechanical equipment status, and predictive maintenance of mechanical equipment. Starting from five dimensions: physical entity, virtual entity, connection interaction, digital twin data, and functional services, this paper explores the key common problems that urgently need to be solved in the field of intelligent mining. The physical entity dimension needs to focus on breaking through the research and development of comprehensive perception and control equipment. The virtual entity dimension needs to conduct in-depth research on physical, behavioral, and rule models. The connection interaction dimension needs to tackle key technologies for underground 5G network transmission in coal mines. The twin data dimension needs to solve problems such as high-performance computing. The functional service dimension needs to develop simulation software and artificial intelligence algorithms to better adapt to the on-site environment. This article looks forward to the development trend of digital twin technology in the field of intelligent mining from the aspects of disaster prevention design, production system design, geological environment prediction in the planning, development, and construction stages of mines, disaster warning and prevention, optimization of production scheduling decisions, and full life cycle management of production equipment in the production and operation stage of mines. It is believed that fine twinning should be carried out for key components or equipment, core links, important or dangerous places, areas, etc.

The intelligent mine comprehensive control platform is an important support for achieving safe and efficient production in coal mines. However, there are still problems in the research and practice process, such as inconsistent conceptual descriptions of the control platform, and deviation from the core development direction in the development and construction of the control platform functions. In order to clarify the development direction and path of the later functional development and on-site application process of the control platform, the essence of the control platform is analyzed. It is concluded that the essence of the control platform centered on data flow involves three aspects: data access, data fusion, and data comprehensive application. By comparing and integrating the existing intelligent mine acceptance management measures of the National Energy Administration, major coal producing provinces, and major energy central enterprises, the functional requirements of the control platform are subdivided into basic support functions, expanded supplementary functions, and key core functions. Taking the three major functions as the main line, this paper summarizes the research and application progress of control platforms and proposes a development path. The basic support functions have problems such as insufficient data access stability, maturity, and practicality. The functions should be developed towards standardization and reliability. Expanding supplementary functions can meet the personalized needs of enterprises, but it is not the core development direction of intelligent comprehensive control. It should be developed towards practicality and complementarity to assist in achieving key core functions such as global interconnection, collaborative control, and independent decision-making. The key core functions should be developed towards standardization and stability. Currently, research on key core functions lacks specific standards and details. In order to achieve the goal of intelligent mine construction, it is necessary to solve the practical difficulties and problems in coal mine sites, and gradually explore new application scenarios and potential needs.

This paper reviews the general situation of the development and innovation practice of China's coal industry in the past 50 years promoted and witnessed by the Journal of Mine Automation from coal mine mechanization to automation and intelligence. This paper expounds on the innovation process of coal mine automation and intelligence. It focuses on the analysis of the research and development and practice of coal mine information infrastructure, automation and intelligent equipment and systems. The integration and unified hosting of heterogeneous networks is the information foundation for coal mine automation and intelligence. On the basis of the continuous maturity of the heterogeneous network of the backbone network and access network, the wired communication transmission rate has reached over 10 Gibit/s. The wireless communication technologies such as 5G and WiFi6 have been widely applied, providing a reliable communication platform for the intelligent construction of coal mines. Wired communication, wireless communication, IP broadcasting, personnel locaiton monitoring system, and video monitoring system are integrated to build a multi-network integrated communication system, achieving integrated carrier network and unified location service. The development of intelligent automation equipment in coal mines is rapid. It explores adaptive cutting technology based on transparent geology, automatic coal release control technology on the basis of technologies such as memory cutting of coal mining machines and automatic following and moving of hydraulic brackets at coal mining working face. On the basis of achieving profiling cutting, positioning navigation, and remote control, the excavation working face has made breakthroughs in technologies such as drilling anchor integration, multi-machine collaboration, and cutting template planning of roadheader based on geological model, achieving good results. The development of intelligent equipment for coal flow transportation systems is supported by intelligent variable frequency energy-saving transmission. The integrated research and application of coal mine robots are achieved. The mature application of inspection robots is obtained. The breakthroughs in intelligent auxiliary operation robots are achieved. The development of a multi-scene robot cluster scheduling and command system forms a robot cluster. The automation and intelligent construction of coal mines have officially entered the stage of intelligent mine comprehensive control from single system automation, comprehensive mine automation, and the Internet of Things. The realization of intelligent perception, intelligent self-control, high-speed transmission, collaborative control, and intelligent decision-making is an inevitable requirement for the development of intelligence. The paper proposes key directions for the iterative development of coal mine intelligent technology, including the establishment of high-precision transparent geological models, the normal and reliable operation of unmanned operating systems, the construction of intelligent compatibility and collaboration mechanisms for coal mine giant systems, the intelligent collaborative control of the entire process of 'excavation, mining, transportation, washing, and sales', and the optimization of a flexible coal production and supply system.

As a typical complex production system with multi business collaboration, coal mines face problems such as poor collaboration and linkage in safety, production, and operation under the dynamic sales demand and uncertain production environment. Digital twin technology can provide technical support for achieving data fusion, collaborative control, and intelligent linkage in the global business system of coal mines. This article analyzes the integration and collaborative control of diversified businesses in coal mines from two aspects: internal integration of professional businesses and integration between professional businesses. The internal integration of professional businesses includes three parts: safety monitoring business integration, production collaboration business integration, and operational business integration. We have constructed a business dynamic collaborative management and control architecture based on digital twins. It includes a physical object perception layer, a virtual space simulation layer, and a collaborative management and control decision-making layer. A triple-driven dynamic collaborative control model for the coal mine global business has been proposed. It includes 'proactive static planning of decision algorithms, predictive collaborative control of twin models, and real-time data dynamics collaborative control'. In the twin world, the multi-business virtual model for coal mine 'safety - production - operation' is constructed. The proactive static planning for safety assurance, production linkage, and business management is carried out to formulate the optimal initial work plan for business collaborative control. The numerical simulation method is used to achieve the predictive operation of virtual models in the information world. After the effectiveness of control measures is verified, decision instructions are promptly issued to the physical world. Therefore, the disturbances from passive processing after the event are transformed into active control before the event, improving the effectiveness of control decisions. When there are unforeseen disturbances in the twin world during the operation of coal mining enterprises' business, based on real-time monitoring data, decision algorithms are used to determine the level of disturbance events. The corresponding emergency plans are triggered. The dynamic collaborative management and control of the diversified business of the enterprise are achieved.

The comprehensive control of coal mine disasters is a key problem to be solved in the process of intelligent mine construction. It is an inevitable requirement for the construction of intelligent mines to realize the normalization control of coal mine disasters with the help of digital twin technology. Based on the connotation and essence of the digital twin, this paper analyzes the recognition rule of the digital twin and puts forward the application mode of digital twin technology in coal mine disaster research combining with data interactive process of mine disaster digital twin. Real-time monitoring is carried out by coal mine underground disaster monitoring sensor. The monitoring data is uploaded to the cloud through the edge communication module and cloud communication module. The digital twin numerical simulation software is deployed in the cloud. The monitoring data uploaded by the sensor is used as the initial condition parameter, boundary condition parameter and effect verification parameter. The best optimization parameters and solutions are sought through real-time simulation analysis and continuous trial and error. When the technical means are mature in the twin world, they can be used to analyze, judge and make decisions on the best parameters and solutions for virtual entities. The decision instructions can be sent to underground actuators to control the action of disaster prevention equipment. This paper discusses the practical application of digital twin enabling disaster predictive management and control from three aspects: disaster monitoring scheme optimization, disaster rehearsal and precise planning of disaster avoidance route, and post-disaster rescue scheme formulation and accident investigation. Based on the 'cloud-pipe-edge-end' architecture of the industrial Internet, the digital twin service system for coal mine disasters is constructed. The key technologies of digital twin for mine disasters are analyzed. The technologies include intelligent sensing and execution equipment for coal mine disasters, simulation software for coal mine disasters and common support technologies. It is expected to provide reference for the construction of digital twin-enabling intelligent mines.

The shallow thick coal seam in the western mine area in China usually adopts the extraction ventilation method. The surface air leakage makes the wind flow disorderly, and the oxygen of the air penetrates the goaf and interacts with the residual coal in goaf to oxidize the coal. Therefore, the coal spontaneous combustion is likely to occur, and the harmful gas such as carbon monoxide exceeds the standard, causing seriously effects on the normal mining of the mine. At present, field measurements, theoretical analysis and experimental research methods are generally used to analyze the gas concentration field and temperature field of coal spontaneous combustion in goaf caused by surface air leakage. However, the spontaneous combustion experiment of surface air leakage is relatively complex. It is difficult to use theoretical analysis and experimental research methods to obtain the influence law of surface air leakage on coal spontaneous combustion in goaf from a three-dimensional perspective.In order to solve the above problems, according to the characteristics of shallow thick coal seam in northwest China, a three-dimensional numerical calculation model is established. Combined numerical simulation and field measurement methods are used to analyze the distribution of 'three zones' in the surface air leakage goaf area of shallow thick coal seam. The methods also analyze the distribution law of O2 concentration field, CO concentration field, temperature field and pressure field in goaf under different working conditions. Moreover, the field validation is carried out by the ZD5 coal mine fire multi-parameter monitoring device. The results show that the distribution of the 'three zones' and the O2 concentration field in goaf are greatly affected by the surface air leakage. It is found that O2 is easily accumulated at the top of the goaf, which changes the gas flow field distribution in goaf. The concentration range of high volume fraction O2 (volume fraction 18%-23%) in goaf is 0-270 m along the strike direction of the goaf and 3-20 m along the vertical direction of the goaf. In particular, O2 is sufficient in the range of 0-80 m along the strike direction of the goaf and 3-8 m along the vertical direction of the goaf. In this area, there is a certain amount of residual coal and heat is not easily dissipated, raising the risk of coal spontaneous combustion. The pressure at the corner of return air roadway in goaf is the smallest, -10 Pa, the pressure at the return air roadway outlet is the lowest, and the pressure at the air inlet is the highest. The pressure gradually increases along the inclined direction, the vertical direction and the strike direction. The temperature distribution is similar to the CO distribution in goaf. The goaf floor is little affected by the air leakage from the surface, but largely affected by the corner of the intake air roadway of the working face. The heat accumulation and CO accumulation are basically the same as the situation of no air leakage. From the middle of the goaf, the temperature and CO are mainly affected by the surface air leakage, presenting an 'O' ring distribution. At the top of the goaf,the temperature and CO reach maximum values at the junction of each fracture zone and the goaf, then decrease along both sides. The maximum value appears at the junction of the deepest fracture zone and the goaf.

In view of problem that current numerical simulation of combined hazards of gas and coal spontaneous combustion in goaf only considers fluid effects, and does not consider influence of other physical fields, multi-field coupling numerical simulation software Comsol-Multiphysics is used to establish coupling model of gas and coal spontaneous combustion in goaf. Distribution law of gas and O2 in stope of working face and goaf is analyzed, and influence of drainage volume and air intake volume on gas concentration in high-level drainage roadway and O2 concentration in floor of goaf is explored to comprehensively determine the optimal drainage volume and air intake volume. The results show that with the increase of drainage volume, gas drainage concentration increases first and then decreases, and the width of oxidation temperature rise zone in goaf has a positive correlation with growth,comprehensively considering gas drainage effect and natural ignition prevention, the optimal drainage volume 90 m3/min is recommended for high-level drainage roadway; with the increase of air intake volume, gas concentration and scalar quantity of the high-level drainage roadway first increase and then decrease, the width of oxidation temperature rise zone on the air intake side of the goaf obviously increases, and the maximum at 109.3 m, the width of oxidation temperature rise zone on the return air side has a small change,comprehensively considering gas drainage effect and natural ignition prevention, the optimal air intake volume at the test face is 1 500 m3/min.

Equus Linnaeus animals, as large non-ruminant herbivores, harbor a diverse array of microorganisms in their gastrointestinal tract, and the microbial composition varies across different segments of the gut. These microorganisms play a crucial role in the efficient utilization of feed, especially for nutrients that cannot be readily degraded by endogenous enzymes or are minimally susceptible to endogenous enzymatic breakdown. The intestinal microbiota of Equus Linnaeus animals interacts with the host, participating in energy metabolism and immune regulation. External factors (such as diet composition and environmental conditions) and internal factors (including age, gender, and genetic background) can disrupt the balance of intestinal microorganisms, leading to digestive system disorders such as diarrhea, colic, and colitis. The article provides an overview of core microbial communities in the Equus Linnaeus animals intestinal tract, community structures in different gut segments, factors influencing gut microbiota, and the relationship between gut microbiota and overall health. The aim is to serve as a reference for research related to the intestinal microbiota of Equus Linnaeus animals. [ABSTRACT FROM AUTHOR]

To explore phosphorus (P) rate effect on protein and metal content of flaxseed, and to provide a basis for establishment high efficient P fertilizer management, field experiments were conducted in 2018 and 2019 with 2 factors randomized block by 5 P levels (0, 40, 80, 120, 160 kg P2O5 · hm-2) for 3 cultivars (Longyaza 1, Longya 14 and Zhangya 2). Seed protein, potassium, calcium, sodium and magnesium contents of flaxseed were investigated. Results showed that flaxseed yield, seed potassium, calcium and magnesium contents improved in different degrees with P application rate. Compared with no P, average seed yield, seed potassium, calcium and magnesium contents increased 17.6%, 11.6%, 17.6% and 12.5% respectively. Phosphorus did not affect seed sodium and protein contents. Considering yield, seed potassium, calcium and magnesium contents between years, P rate of 80 kg P2O5 · hm-2 was the most appropriate, which synergistically increased yield, flaxseed calcium and magnesium contents, and also reduced environmental risks by excess P fertilizer. [ABSTRACT FROM AUTHOR]

For problems that the choice of pumping time and pump type of beam tube monitoring system with long gas pipeline lacks theoretical support and only depends on experience, so as to lead large error, flow conductance of beam tube and effective pumping speed and pumping time of beam tube vacuum system were calculated through discriminating gas flow state in gas pipeline. Three kinds of vacuum pump and gas pipeline with four length were selected for combination experiment to verify accuracy of theoretical calculation conclusion. Based on calculation and experiment results, suggestions for selecting gas pipeline and pump in beam tube monitoring system are put forward.

In view of problems of water wasting and environment pollution existed in industrial circulating water system, a polarizing control system of industrial circulating water based on ARM was designed. The system uses polarizing energy detection circuit to real-timely detect water quality parameters of circulating water, then the parameters are processed by STM32F103 to get PWM polarizing energy control signal which is integrated, isolated and amplified by polarizing energy output circuit to drive polarizing body, so as to produce polariaing field to act on circulating water. The actual application showed that the system can control circulating water system running at high concentration rate, which replaces dosing treatment process of circulating water system and reaches goals of reducing water consumption and preventing water pollution.

The all-optical vector signal processing technology is of great significance in the evolution of optical network due to its low delay and high efficiency. Therefore, a comprehensive introduction to the technical background and application scheme of the current all-optical signal processing was given. The all-optical signal modulation format was firstly introduced, and the basic characteristics and receiving modes of each modulation format were described. Furthermore, the nonlinear optical effects, which were the basis of all-optical signal processing, were classified and introduced. The occurrence conditions, occurrence process, optical phenomena and common nonlinear media were also illustrated. The advantages of all-optical signal processing technology were briefly introduced and three typical research fields of all-optical signal regeneration, all-optical format conversion and all-optical phase quantization were introduced in detail. Finally, the application prospect of future all-optical vector signal processing technology was prospected. [ABSTRACT FROM AUTHOR]

In order to study the law of stress evolution of coal contained gas and characteristics of gas radiation in acoustic field, a self-developed coal gas desorption set was used to build physical model of coal gas radiation in acoustic field. The total stress of coal body, gas pressure and velocity of gas radiation in the process of coal gas radiation in acoustic field were monitored. Experimental results show that the total stress of coal body decrease with time according to logarithmic law in acoustic field. Experiments also show that the mechanical damage effect and periodic vibration effects of acoustic waves can promote coal gas desorption and radiation. [ABSTRACT FROM AUTHOR]

Air samples were collected at urban and rural sites in Xiamen from January to April 2014. The concentrations of 48 ambient volatile organic compounds (VOC) species were measured by the method of cryogenic pre-concentrator and gas chromatography-mass spectrometry (GC/MS). The ozone formation potential (OFP) of VOCs was also calculated with the method of maximum incremental reactivity (MIR). The results showed that the average mixing ratios of VOCs in winter were 11.13 x 10(-9) and 7.17 x 10(-9) at urban and rural sites, respectively, and those in spring were 24.88 x 10(-9) and 11.27 x 10(-9) at urban and rural sites, respectively. At both sites, alkanes contributed the most to VOCs, followed by aromatics and alkenes. The ratios of B/T showed that vehicle and solvent evaporation were the main sources of VOCs at urban site. While at rural site, transport of anthropogenic sources was another important source of VOCs besides local biomass emissions. Ten main components including propene, n-butane, i-butane, n-pentane, i-pentane, n-hexane, benzene, toluene, ethylbenzene and m/p-xylene accounted for 61.57% and 45.83% of total VOCs at urban and rural sites in winter, respectively, and 62.83% and 53.74% at urban and rural sites in spring, respectively. Aromatics contributed the most to total OFP, followed by alkenes. Alkanes contributed the least to OFP with the highest concentration. C3, C4 alkenes and aromatics were found to be the more reactive species with relatively high contributions to ozone formation in Xiamen. Comparing the average MIR of VOCs at the two sites, it was found that the reactivity of VOCs at rural site was higher than that at urban site.

The study on the spatial distribution of near surface air pollutants carbon dioxide (CO2) and particulate matters (PM) is essential for understanding the pollution characteristics with mobile measurements. Near surface concentrations of CO2, PM and meteorological parameters were measured in Xiamen city, China along the route passing through different functional areas using the mobile laboratory during different time periods of the day [09:00- 12: 00, 13 :00- 16 : 00, 22 : 00-01 : 00 (local time) ] in spring (April) and fall (November), 2013. Carbon dioxide, PM and meteorological parameters data were analyzed for the spatial distribution of CO2 in different functional areas and the relationship of CO2, and PM2.5. During the study period, the measurements started at the northern part of the city, across the suburban area and ended at about 60 km in the southern Xiamen. The spatial distribution of CO2 along the road showed a high CO2 level in the central area of the city and low values in the outlying areas. Different CO2 concentrations were observed at different functional areas because of the differences in emissions from traffic and industry, the emission and absorption by vegetation, and meteorological conditions. The concentrations of CO, at different areas fell into the following order: areas with heavy traffic (477.33 micromol.mol-1 +/- 6. 11 micromol.mol-1 ) > commercial residential area (454. 95 micromol.mol-1 +/- 5.45 micromol.mol-1 ) > the naturalscenic spot (441.01 micromol.mol-1 +/- 6.24 micromol.mol-1 ) >cultivated land (436.79 micromol.mol-1 +/- 1.87 micromol.mol-1 ) > mountain woodlands (434.06 micromol.mol-1 +/-0.31 micromol.mol-1 ). The average CO, concentration in spring 2013 was measured to be 452.04 micromol mol -1 +/- 20.24 micro.mol. mol-1 with the maximum value of 533.10 micromol.mol-1 at the heavy traffic area in downtown Jiahe on April 12, 2013 and the minimum value of 413.25 micromol.mol-1 on April 10, 2013 at the mountain woodland, which is about 23 km away from the downtown area. The mountain woodland is surrounded by a reservoir and woods and regarded as the background area. The average CO2 concentration in fall 2013 was determined to be 451.80 micromol.mol-1 +/-21.56 micromol.mol-1 with the maximum value of 526.45 micromol.mol-1 at a heavy traffic area of Xiahe road in downtown, on November 19, 2013 and the minimum value of 415.01 p.mol.mol-' at the mountain woodland on November 10, 2013. This phenomenon was called "CO2 dome" by Idso in 1998. In addition, the CO2 concentrations tended to be the highest at night (22:00-01:00) and the lowest in afternoon (13:00-16:00). During overcast days, the CO, concentrations were generally higher than those on clear days. At different functional areas, differences between nighttime (22:00-01:00) and daytime (09:00-12:00 and 13:00-16:00) ranged from -0. 66-29.48 micromol.mol-1 in spring and from -4.01 micromol.mol-1-33.69 micromol.mol-1 in fall. The CO2 concentrations at the urban and the suburban areas were also different in spring and autumn and at different time of the day. The CO2 concentration was in significant correlation with PM2.5 (R =0.73, P < 0. 01) indicating the important impact of traffic pollution on the ambient CO2 concentration.

Objective: To investigate the pharmacokinetics and bioavailability of ginsenoside Rg1 in rats., Methods: Ginsenoside Rg1 was oral administered or intravenous administered to each rat. The plasma concentration of ginsenoside Rg1 was estimated by RP-HPLC. 3P97 software was used to calculate pharmacokinetic parameters., Results: Main parameters of ginsenoside Rg1 after oral or intravenous administered were: AUC(0 --> t), 322.70 +/- 20.78, 99.76 +/- 8.91 microg x h/mL, CL 0.08 +/- 0.02, 3.01 +/- 0.69 L/(kg x h), V 0.23 +/- 0.01, 22.75 +/- 2.09 L/kg, t1/2alpha 0.48 +/- 0.18, 0.87 +/- 0.21 h, t1/2beta 19.57 +/- 2.81, 18.68 +/- 2.74 h, MRT6.91 +/- 0.99, 8.15 +/- 1.05 h(-1), respectively. The relative oral bioavailability of ginsenoside Rg1 was 2.5%., Conclusion: The oral bioavailability of ginsenoside Rg1 is very low.