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Three principal components (cellulose, lignin, and hemicellulose) of coconut shell (CS), an abundant tropical biomass, were quantified using the Van Soest method. It was observed that CS had a high content of hemicellulose (30% of the raw CS material). The present study was undertaken to investigate the extractability of hemicellulose from CS obtained by ultrasound-assisted potassium hydroxide solution with the hydrogen peroxide method. The ultrasonic treatment and sequential extractions with alkali and alkaline peroxide under optimal conditions led to a release of more than 93% of the original hemicellulose. The effects of experimental variables, including pH value, reaction temperature and time, hydrogen peroxide content, and magnesium sulfate dosage on hemicellulose content were investigated. The obtained hemicelluloses were characterized by Fourier transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC), and comprehensive thermal analysis (TGA), which showed that potassium hydroxide significantly affected the yield of relatively pure hemicellulose.

The optimal design for computer control software is studied. Since computer control software is susceptible to interference during the control process, a computer control software design model based on improved PID algorithm is proposed. The PID algorithm is combined with particle swarm algorithm to calculate PID control parameters, which is viewed as evolutionary particles of the particle population, and given a certain flight speed in the search space, the speed of the particles will be adjusted iteratively and dynamically in accordance with the experience of population’s evolution calculation, in order to achieve computer control software design. The simulation results show that the proposed algorithm applied for computer control software design, can improve the control precision and meet the actual needs of computer control.

This paper studied Lucene search engine technology in enterprise content management system and make it effectively expanded. It implemented four function modules in the architecture of full-text retrieval based on Lucene: Text analysis module, index module, query module and store module. The intelligent enterprise content management system is reflected in a perfect combination of intellectual technology which includes data retrieval and the modern open source frameworks. It intensified contents processing analyzing functions.

Aiming at the access control problem of the cloud service platform, puts forward the control scheme of multi-level system for multi type coordination.By the definition of cloud services platform multi access control object system,constructs multidimensional Boolean relation matrix. The semantic relation of Boolean matrices, design of large-scale complex network node control system model, and simulate the hierarchical network loop control model.Through the analysis of network model, shows that the research results can better support for cloud services platform in multi-level access, dynamic authorization complexity problems in management control.

Under the premise of determined transportation tasks and determined collaboration tasks assigned, this paper defines four factors that influence the distribution of collaborative logistics profits: external logistics providers competing risks, uncertainty external transport risks and information sharing and collaboration satisfaction between internal collaboration logistics providers, established a profit distribution model uses an improved correction factor Shapley value. Finally, we use an example to prove the rationality and validity of the model, thereby protecting the smooth coordination of logistics and sustainable development.

The study about the impact of implant denture on getting stuck between the teeth is rarely reported. Computational modeling and simulation was performed in this study in order to investigate the effect of planting denture on interdental food impaction. Four groups of experiment were designed; Simplified teeth models were established and meshed; loads were applied to the models and boundary conditions were constrained in the state of teeth chewing. Finite element method was employed to analyze the deformation of teeth and impacted object. When the force exerting on the impacted object is in the range of 0-5.5N, the distance between denture and tooth after planting denture is less than that between the normal teeth. The deformation is the minimum when the denture is lower than tooth. When the force exerting on the impacted object is in the range of 0-5.5N, interdental food impaction is easier to occur after planting denture, and Interdental food impaction may be more likely prevented when denture is lower than tooth.

Currently, all the global petroleum exploration and production companies are facing the pressure of lowing operating costs and improving labor productivity, now the emergence of the digital oilfield brings hope to these companies. This paper expounds the difficulties that the domestic digital oilfield encountered in the design of construction, and combining with the actual need of the oil fields in the development of oil-gas exploration, especially discusses the common problems in the construction of current digital oilfield and analyzes the existing oilfield technology and the development needs, finally, it put forwards feasible solutions.

Phloroglucinol-resorcinol-formaldehyde organic aerogels (PRF) were prepared using phloroglucinol, resorcinol and formaldehyde in a sol-gel process, solvent replacement and drying at room temperature. The phloroglucinol-resorcinol-formaldehyde carbon aerogels (CPRF) were prepared by charring the PRF at high temperature under the aegis of helium flow. The microstructure of CPRF was characterized by infrared spectroscopy, specific surface area analyzer and scanning electron microscopy. The results showed that the CPRF had continuous network structure and high specific surface area.

A copolymer was prepared from itaconic acid (IA) and sodium allysulfonate (SAS). The structure of the IA/SAS copolymer was characterized by the means of FTIR. The performances of scale inhibition, dispersion and biodegradability of the IA/SAS copolymer were studied. The results showed that the IA/SAS copolymer had good scale inhibition and dispersing performance. The scale inhibition rate on calcium carbonate was 93% when the copolymer was 20 mg·L-1. The scale inhibition rate on calcium phosphate was 92% when the copolymer was 24 mg·L-1. The copolymer had good biodegradation performance and biodegradation rate could reach 69.5% after 28 days.

In this paper, the compound shellac fruit wax was prepared by SiO2 aerogel, shellac, sodium hydroxide, fungicide. The obtained fruit wax was used to preserve the mango in tropical area. The results show that the compound shellac fruit wax with 0.2% SiO2 aerogel can suppresses water loss, adjust the respiration, reduce the rot rate, thus extending the preservation time of mango.

Cellulose is one of the most abundant renewable resources on the earth and could meet the increasing demand for environmental protection property and biocompatibility of materials. In recent years, ionic liquid, as a new type of environmentally-friendly medium and soft functional material, has gained widespread concern, for it has provided broad space for the further development of cellulose chemistry. This paper selects 1 - propenyl-3 - methylimidazolium ionic liquid to dissolve and reproduce the cellulose, thereby preparing the gel-type wood-based composite. The reformed fiber bundles constitute an unclosed three-dimensional cross-linked network as the support frame which owns the microstructure similar to balsa wood as well as the stable chemical and physical properties. Its oven dry density is 0.221 g/cm3and the porosity is over 87%. This kind of gel-type wood-based composite prepared by the green chemical processing could fix and store the carbon adsorbed by trees, which is conductive for the environmental protection.

It is a big problem how to finish intraoperative functional localization precisely, rapidly and no-invasively during neurosurgery operations. Previous researchs shown that the SCP (slow cortical potential) is a specific ECoG (electrocorticography) rhythm in the cortical motor areas. A real limb movement induced ERP(event-related potential) of SCP in the motor cortex. In this study, based on ERP of SCP phenomenon, wavelet analysis and SVM (support vector machine) were used to extract and classify the ERP of SCP feature, an algorithms for classification of the ERP in the motor regions utilizing experimental data was designed and verified. Then the results of classification were used to mapping the boundary curve of motor cortex functional areas. Results demonstrated that the accuracy of localization detection was 93.75% , the degree of accuracy was less than 5 mm, with an operation time of 2 minutes, avoiding the problems of cerebral cortex injury and epilepsy onset. The cerebral motor cortex functional localization based on SCP in ECoG detecting technique is accurate, safe and rapid.

In this paper, we had a field test study in mud-pumping of the subgrade. During the experiment, from the process and the parameters, and based on the laboratory tests, a series of tests on the soil at the mud-pumping of the subgrade have been done before and after the improvement of the physical parameters.Studies show that the adopted materials, processes and parameters to be successful.

By the requirements of reliable wireless communication, a new composite code scheme is proposed for orthogonal spreading codes in order to improve synchronization and error performance, which is based on certain criteria to select the composite codes. Simulation shows that the correlation property of the screened composite codes and the bit error rate performance are better than that of other composite codes.

In city parks, some plants degrade seriously because of human activities and lack of sunlight.A large number of bare soils stand out against the green background and have a tremendous negative impact on cityscape,ecological environment, and residents’ health.In this study, distribution of bare soils and their areas in Mianyang wuyi square were investigated. According to the characteristics,the bare soils are divided into three categories.Some normal ways to restoring landscape and ecological effects of bare soils were also pointed out, such as organic covering, inorganic particle covering and small square construction.

The absorption heat pump was studied with finite time thermodynamics. A four reservoirs model of absorption heat pump which is treated as an irreversible Carnot heat pump driven by an irreversible Carnot heat engine was established considering the heat resistance and the irreversibility of the internal cycle. A generalized optimization relationship between the main parameters and the corresponding conditions were derived. It is show that, two internal irreversibility parameters, the heat engine cycle and the heat pump cycle has different effects on system performance, and the reduction of the friction, heat loss, and internal dissipations of the equivalent heat pump cycle are more important than its reduction of heat engine cycle.

During handling airplane low-rigid parts, it often horizontally hanger it with rope or sling. Combined with frictionics, this article analyses the force in vacuum sling of aeronautical low-rigid parts and gets the corresponding conclusion to design hangers for reference.By establishing finite element model, the deformation of hoisting is static analysed by ANSYS.The research results is to provide necessary conclusions in effectively resolving the optimization of designing of vacuum lifting system.

How to use the waste heat deeply are a critical issue for BCHP (Building combined cooling heating and power) system. A BCHP system with a soil source absorption heat pump driven by the waste heat is proposed. The system is composed of an internal combustion engine, a soil source absorption heat pump driven by the flue gas, and other assistant facilities, such as pumps, fans, and end user devices. In the winter, the flue gas is used to drive absorption heat pump to recover the waste heat of the soil source and the condensation heat of the flue gas simultaneously, and in the summer, the waste heat of the flue gas is used to drive absorption heat pump to cooling, and the heat sink is the soil. In the paper, the configuration of this kind of system is designed, and the energy analysis of the system is done all the year. Compared with the conventional BCHP system, the operation cost is lowered greatly and the increased investment could be returned within one year. It is show that the system is the efficient integration of cleaning energy, renewable energy, the discharge of the flue gas could be reduced to below 30°C, and the water steam could be catch to avoid the white smoke of the stack. The energy saving in space heating could be 66% compared with the conventional BCHP systems.

Through case studies of Japan's post-disaster reconstruction, the author thought that Wenchuan earthquake reconstruction needed to evaluate. After researched and analyzed the situation and characteristics of the city's reconstruction in three represents which are the new county seat of Beichuan, Weizhou in Wenchuan and Dujiangyan City, the author proposed 10 selected evaluation elements, in order to supply a technical reference for building evaluation system and carrying out the evaluation.

In this paper, the transient emissions from vehicle engines was studied, measurement methods and corrections required for higher precision measurements of transient indirect emissions was discussed. Various operating conditions such as cold start, constant torque increasing speed, constant torque reducing speed emissions were considered and the corresponding emission characteristics were obtained and analyzed.

Taking Wusongshan Tunnel in Tongling City as an example, three-dimensional numerical simulation of new large span highway tunnel built directly through gob of steep coal seam is carried out to study the response of tunnel structure induced by mining. The results showed that, (1) Though immediately backfilling after extraction can prevent the tunnel structure from impact of mining below the tunnel, it is still necessary to forbid extraction below the tunnel consildering the duration time of the extraciton and backfilling activity. (2) Considering the long-term settlement of gob of steep coal seam, net height of the tunnel should be enlarged 50cm to ensure enough space for operation. (3) The tensile and pressive stress of the support structure in the bottom and roof section of the gob are obviously high than other, so comperihencive measures should be taken to reinforce the structure, especially to increase the tensile strength in axial direction. (4) Fortification intensity can be reduced but the fortification should be enlarged if the continuous reinforcement by steel bar is used at the radial construction joints. Based on these results, treatment plan were developed for Wusongshan Tunnel, which can also be refered for other similar projects.

Taking Wusongshan Tunnel in Tongling City as an example, two-dimensional numerical simulation of new large span highway tunnel directly through gob of steep coal seam were carried out to study the response of surrounding rock induced by mining. The actual location and scale of the ground fissure consistent well with the simulation results, which verified the analysis. The results showed that, different from those in gob of horizontal or gently inclined coal seam, the response of surrounding rock in gob of steep coal seam have the following characteristics: (1) shallow mining affects significantly on the values of settlement of earth surface and the tunnel, and deep mining on the scope; (2) in the shallow layer, a small scale coal being reserved or being effective filled after excavation can benefit greatly to the safety of structure and stability of the surrounding rock; (3) sharper uneven settlement would occour at the floor than the roof of coal seam, which can threaten the tunnel structure and should attract more special attention; (4) for this project, deep faults affect the safety of structure of tunnel and stability of surrounding rock also. Based on these results, treament plan were developed of Wusongshan Tunnel, which can also be refered for other similar projects.

Aiming at uncertainty of process plans in the process decision making, the paper introduced a method based on ant colony optimization (ACO) to find out the set of optimal solutions for multi-objective machine tool selection. The Analytic Hierarchy Process (AHP) was applied to simplify process decision making plans, and the structural diagram of AHP was made up according to the different demands of manufacturing engineer. By means of the examples the different elements to different manufacturing processes are comprehensive evaluated, and the most splendid process scheme is evaluated, meanwhile the feasibility of the proposed method applying process decision making is verified.