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In order to explore the effectiveness of the laboratory’s self-developed equipment - horizontal box cage stacked peanut pods room temperature ventilation drying equipment, this study used this equipment to conduct drying experiments on newly harvested peanut pods. The research focused on analyzing the drying rate of peanuts, changes in temperature and humidity within the pile, and energy consumption, and the results were then compared with natural sun drying and similar drying equipment. The research has found that under the same weather conditions (mainly cloudy and rainy weather), the moisture content of peanuts reduced from an initial 43.77% to below 10% within 9 days with a horizontal box cage stacked peanut pods room temperature ventilation drying equipment. The drying rate was 43% higher than that of natural drying. The drying energy efficiency of peanut pods was 2.64×106 J/kg, and the moisture content of the inner and outer layers of the stacked peanut pods decreased uniformly. This study has demonstrated that the horizontal box cage stacked peanut pods drying equipment can be used for the emergency drying of newly harvested peanut pods.

In order to study the quality change of coffee malt premixed powder with the extension of storage period, the coffee malt premixed powder was stored at the environment where the temperature is 25 ℃ and 35 ℃, respectively, and the relative humidity is 50% respectively. Its moisture, fatty acid value and falling value were monitored during the whole storage period. The volatile compounds were separated and identified by solid phase microextraction accompanying gas chromatography-mass spectrometry during the whole storage period. The results demonstrated that with the extension of storage period, the overall moisture content shows a falling trend, while the fatty acid value and falling value show an overall rising trend. The higher the storage temperature, the more significant the change is 41 kinds of main volatile compounds of coffee malt ready mixed powder were identified. It mainly includes 13 kinds of aldehydes, 15 kinds of heterocycles, 7 kinds of esters, 4 kinds of alcohols and 2 kinds of ketones. Among them, the relative concentration of aldehydes (n-hexanal, nonanal, trans-2-nonenal) showed an increasing trend with the extension of storage period.

Background: The pathogen of angiostrongyliasis is the parasite Angiostrongylus cantonensis, and the transcriptome profiling of the male adult was unclear. We aimed to understand how the male adults adapt, so the expression profile of A. cantonensis adult males was analyzed. Methods: In order to improve the understanding of the transcriptome of adult males, RNA from three groups of male adult A. cantonensis was extracted and reverse transcribed to construct cDNA libraries. After sequencing, annotation of unigenes and transcripts was performed by querying the NR (Non-Redundant Protein Sequence Database), GO (Gene Ontology) and COG/ KOG (Clusters of Orthologous Groups of proteins/euKaryotic Ortholog Groups) databases. Results: For each group of adults, 43,260,894 raw reads and 43,200,341 clean reads were obtained. After successful assembly, 87,649 unigenes and 146,895 transcripts were obtained. Annotation of the unigenes and transcripts was identical and male adults expressed a series of genes encoding proteins specific to the male gender at the adult stage, such as proteins involved in energy metabolism, energy synthesis and transport. Expression of the ribosome pathway suggests a relationship with the physical activities during the adult male stage. Conclusion: The transcriptome analysis is a good reference to understand further the expression profile of male adult A. cantonensis.

With the rapid development of satellite internet, the shortage of bandwidth and spectrum resources has become increasingly prominent.Satellite laser communication has the characteristics of large bandwidth and no spectrum constraints, which makes it an effective means to alleviate the shortage of radio frequency resources and improve the communication bandwidth.Through the investigation of the development of satellite laser communication at home and abroad, this paper summarizes the future technical development trend in this field.The key technologies such as network reconstruction and efficient coding are studied via simulation, which provide theoretical and technical reference for the research of satellite laser communication in China.

Objective: To optimize the drying characteristics of dragon fruit freeze-drying process. Methods: Based on the fractal theory and the theory of heat and mass transfer in porous media, the COMSOL software was used to numerically simulate red pitaya slices with a thickness of 8, 10, 12, 14 mm and a radius of 40 mm to simulate the sublimation and drying stage of pitaya. The heat and mass transfer process in the internal porous medium, the real-time displacement of the ice interface during the ice sublimation process is obtained, the sublimation period is predicted, and the experimental verification is carried out. Results: The simulated data were in good agreement with the experimental data, and the error was small. The maximum relative error of dehydration rate was 12.6%, and the absolute error was 0.18 g/h; the maximum absolute error of water content was 5.4%. Under the same initial quick-freezing temperature, with the increase of thickness, the time of sublimation drying stage increases nonlinearly; the larger the pore diameter of dragon fruit, the larger the effective diffusion coefficient, the faster the drying speed, and the lower the product quality. Conclusion: Based on the fractal theory, a good numerical simulation of the freeze-drying process of dragon fruit can be achieved, and 10 mm is the optimal thickness of red dragon fruit.

In order to realize the synergistic utilization of calcium silicon slag, fly ash and blast-furnace slag, this paper researched on hydration mechanism of calcium silicon slag composite geopolymer through preparation experiments of the calcium silicon slag composite geopolymer under different ratio of fly ash / blast-furnace slag.The results show that the calcium silicate slag base geopolymer is a binary composite cementitious material mainly composed of C—S—H and C(N)—A—S—H, which is formed by the hydration of β-calcium silicate itself and alkali-activated hydration.Compared with crystalline minerals, glass minerals are more prone to reaction with Ca(OH)2 and sodium silicate, resulting in a large amount of unreacted mullite remaining in the hydrates of 7 d when the fly ash / blast-furnace slag ratio is more than 0.5, but the mullite will continue to hydrate with the extension of curing time, and worm-like tetranatrolite and strip-like beidellite will be formed at 28 d.At the same time, when fly ash / blast-furnace slag ratio is 1.0, micromorphology of calcium silicate slag composite geopolymer is the most evenly distributed and dense, and its 28 d compressive strength reaches maximum 37.9 MPa.So, it indicates that the best synergistic effect among calcium silicon slag, fly ash and blast-furnace slag can be released under this condition.

With the full deployment of 5th generation mobile communication network, the optical communication industry has entered the stage of comprehensive and rapid development. According to the demand of data center optical module market, the optical module will develop to high speed and low price in the future. The 400 Gbit/s Quad Small Form Factor Pluggable-Double Density (QSFP-DD) studied in this paper is based on the theory of near Gauss Beam. The optical path is designed and simulated by ZEMAX software, and the spherical parameters are optimized by the optimization function. The coupling efficiency is 74.8%, and the coupling efficiency under different offset is analyzed to get the error range. After analyzing the Fresnel reflection of the contact surface, and comparing the performance of the device under different grinding angles and the high-temperature fiber transmission test of the module, an oblique 8 ° for adaptation is selected. According to the requirements of the protocol, the optical design of this paper with 8 ° angle optical fiber can meet the requirements of the use of the scene.

AlCoCrCuFe high-entropy alloy was fabricated by melting-casting method. The phase structure, microstructure and friction and wear property for this alloy without and with CeO2 doping were investigated by XRD, SEM, EDS, microhardness tester and friction-wear tester, respectively. The results show that AlCoCrCuFe alloy has BCC+FCC dual phase structure. 1%(mass fraction)CeO2 addition improves the diffraction peak of AlCoCrCuFe alloy. The microstructure of two above alloys is typical dendrite structure. The interdendrite region is mainly Cu-rich and Ce-rich area, and the dendrite microstructure is layered grid structure of spinodal decomposition. After CeO2 adding, the microhardness increases from 441.5HV to 475.3HV, and the friction coefficient and the mass loss rate decrease from 0.55 and 1.44% to 0.4 and 1.28%, respectively.

As an emerging two-dimensional layered transition metal disulfide nanomaterial with typical graphene-like structure, molybdenum disulfide (MoS2) nanosheets have attracted wide attention due to their excellent electrical, optical and thermodynamic properties and their large specific surface area, and it is widely used in the field of electrochemistry. The research status and development trends of MoS2-based hybrid nanomaterials in the fields of electrochemical sensors for life, food, drug, environment and electrochemical hydrogen evolution reaction were reviewed.

Reciprocating sliding friction and wear tests were carried out on polyetheretherketone (PEEK) and natural patella cartilage using the pin-on-disk configuration at different normal loads, slipping velocity and friction pairs under 25% fetal bovine serum, where natural femoral cartilage and CoCrMo were used for comparison to PEEK. The influence of normal load, slipping velocity and friction pair on the friction and wear behavior was studied. The results show that under 25% fetal bovine serum conditions, the friction coefficient of femoral cartilage/patella cartilage is the smallest among that of PEEK/patella cartilage and CoCrMo/patella cartilage, the coefficient of friction of PEEK/patella is obviously lower than that of CoCrMo/patella and the wear surface of CoCrMo/patella is more seriously damaged than that of PEEK/patella. The friction coefficient of PEEK/patella decreases with the increase of normal load especially under the low loads (10-20N) and increases with the increase of slipping velocity especially under the high slipping velocity conditions (10-20mm/s). The wear surface damage increases with the increase of normal load and slipping velocity. The normal load is more effective than slipping velocity.

According to the requirements of sustainable development, through scientific planning of engineering design activities, the sustainable concept of "green design" is introduced into the design of transmission line. The green design method is elaborated in four aspects: electrical design of transmission line, design of tower foundation, structural design of tower body and cable design, which guide the "green construction" of saving resources, protecting environment, improving efficiency and ensuring quality, so as to achieve the goal of saving resources and reducing the negative impact on the environment to the maximum extent. Therefore, the sustainable concept of "green design" has far-reaching promotion significance and prospects.

Based on the recently developed active-passive multifunctional all-digital HF surface wave radar hardware platform of Wuhan University, an experiment study of integrated technology for shortwave communication and Over-The-Horizon Radar (OTHR) application is carried out. Firstly, from the point of communication are demonstrated the key technologies of orthogonal frequency division multiplexing (Orthogonal Frequency Division Multiplexing, OFDM) in the short-wave communication. Secondly, from the point of radar detection are analyzed OFDM parameters design guidelines and its impact on the over-the-horizon radar detection performance. After the description of some key technologies related to communication signal demodulation and radar signal processing, the configuration parameters of hardware platform and experimental results are provided. The results show that the OFDM wave is done well in radar-communication integration systems, which is of great significance on the netted OTHR detection research.

Aiming at triple hidden terminal problems in wireless sensor networks,an adaptive duty cycle based multi-channel MAC protocol was proposed,called MCR.MCR efficiently handled triple hidden terminal problems with multiple channel reservation.By minimizing the lower bound of average times of channel switching in MCR,the optimal duty cycle in theoretical analysis was obtained.To investigate values of multiple channel reservation and dynamic duty cycling in MCR,extensive simulation and real testbed experiments were conducted.The results show that compared with other protocols,when the number of channels is larger or loads are heavy,M-cube improves throughput and energy effi-ciency significantly.

AbstractCd(OH)2nanobelts have been synthesized in high yield by a convenient polyol method for the first time. XRD, XPS, FESEM, and TEM were used to characterize the product, which revealed that the product consisted of belt-like crystals about 40 nm in thickness and length up to several hundreds of micrometers. Studies found that the viscosity of the solvent has important influence on the morphology of the final products. The optical absorption spectrum indicates that the Cd(OH)2nanobelts have a direct band gap of 4.45 eV.

BackgroundGabapentin has been adopted in Enhanced Recovery After Surgery protocols as a means to reduce opioid consumption while maintaining adequate post-operative analgesia. The purpose of our study was to review and compare changes in length of stay, opioid use, and patient reported pain scores after the addition of gabapentin into five, distinct pain protocols for posterior spinal fusion in adolescent idiopathic scoliosis.MethodsA retrospective review was completed using a database of electronic medical data from a single pediatric orthopedic healthcare system that was queried for patients with adolescent idiopathic scoliosis who underwent first-time posterior spinal fusion. Perioperative data including demographics, hospital length of stay, surgical details, opioid use, patient reported pain scores, and non-opioid analgesic use were collected.ResultsFrom December 2012 to February 2019, 682 hospitalizations for posterior spinal fusion in adolescent idiopathic scoliosis were identified with complete inpatient data; 49% were administered gabapentin. For the gabapentin cohort, the system saw no statistically significant effect on length of stay or pain averaged over POD#0-3. Opioid use was statistically lower averaged over POD#0-3. Individual sites saw variation on length of stay and opioid use compared to the system.ConclusionIn conclusion, system-wide data showed gabapentin containing protocols reduced opioid use while maintaining clinically equivalent analgesia. However, variations of individual site results make it difficult to conclude the degree to which gabapentin were responsible for this effect.

This paper mainly analyzes and compares several well-known algorithms for indoor positioning. By many nodes jump tests, relation between RSSI and distance and relation between LQI and packet error rate can be obtained. Then based on the relations, LQI confidence coefficient is classified. By comparing these different kinds of algorithms, this paper perfects the algorithm of fuzzy fingerprint indoor positioning, which can shorten the time required to process off-line data. At last, this algorithm was verified by indoor and outdoor experiments, by which we can know that this algorithm greatly lower RSSI error. And it is concluded that this algorithm has a better positioning accuracy.