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Molten slag is a critical material generated during blast furnace (BF) ironmaking. Slag flow behavior in the lower part of BF is closely related to the selection of charge materials, coke packed bed permeability, process stability, productivity, and hot metal quality. To better understand slag flow behavior, a numerical approach was applied to characterize the slag flow through a coke funnel analog and further, in a packed bed. The funnel analog was used to represent the flow of molten slag through the inter-particle voids of a coke packed bed. A critical funnel neck size, through which no slag flowed was experimentally established and confirmed by numerical modeling. The effect of wettability on slag flow shows the existence of an optimal contact angle for smooth slag flow in a funnel. The model was then applied to provide a deeper understanding of molten slag flow behavior in a packed bed, e.g., visualization of accumulation, coalescence, and breakup of slag at a particle scale. Specifically, the results show that the flow characteristics of discrete slag droplets in the packed bed require a particular quantitative approach for estimating the slag holdup. Packing structure, including pore size and particle shape, significantly affects the occurrence of slag blockage and droplet size, even when overall bed porosity is maintained constant. Slag flow along the vertical direction of the packed bed has a pseudo-steady percolation velocity. These results highlighted that this numerical approach is very helpful to understand the slag flow behavior at a particle scale, providing insight into the general features of slag flow as droplets or rivulets.

Slag flow behaviour is critically important in the lower zone of the ironmaking blast furnace, and is closely related to the selection of charged raw materials, coke bed permeability, process stability and hot metal quality. To better understand the effect of slag properties on flow behaviour in the coke bed, a numerical approach was applied to characterize the slag flow through funnel analogues. These analogues were used to represent molten slag flow through the inter-particle voids of a coke packed bed. A critical funnel neck size, through which no slag flowed was experimentally established and confirmed by numerical modelling. The influence of slag wettability on the occurrence of blockage was also determined via numerical modelling. An increase in either contact angle or surface tension can make the occurrence of blockage easier. For a constant neck size, the relationship between surface tension and contact angle is non-linear. The status of the remaining slag in the funnel corresponding to different slag wettabilities was differentiated in terms of the blockage in the upper part and hanging in the lower part of the funnel. Modelling was also undertaken of slag flow through the inter-particle void between spherical particles to evaluate empirical correlations for predicting the remaining slag in the packed bed. These results show that the numerical approach is very useful in providing some level of guidance to help understand and predict the slag flow behaviour in the blast furnace ironmaking process.

Esophageal cancer is one of the most common tumor in the world, and the morbidity rate is as high as 100/100 000 in some parts of China. Therefore, it is important and urgent to explore the pathogenesis of esophageal cancer and find new therapeutic targets for esophageal cancer. In this study, we found that a novel tumor suppressor SPINK5 is significantly reduced in the development of esophageal cancer, and is closely related to the pathological differentiation and lymph node metastasis of esophageal cancer via bioinformatics analysis and esophageal cancer tissue array. Further studies have found that SPINK5 is closely related to Wnt/β‐catenin signaling pathway by bioinformatics analysis and western blot. In esophageal cancer cells, SPINK5 overexpression can inhibit Wnt/β‐catenin signaling pathway. Combined with LiCl or MG‐132 treatment, SPINK5 can inhibit GSK3β phosphorylation and promote β‐catenin protein degradation, thus inhibit Wnt/β‐catenin signaling pathway. In vivo study, SPINK5 overexpression can significantly inhibit the growth of esophageal cancer cells. Our study shows that SPINK5 can inhibit the proliferation, migration, and invasion of esophageal cancer cells by inhibiting Wnt/β‐catenin signaling pathway, and thus plays an important role in the development of esophageal cancer, and may serve as a treatment target of esophageal cancer.

A coupled flow and refractory model (CFRM) has been upgraded to assist engineers in understanding and interpreting the measured refractory temperature distributions in the hearth of a blast furnace...

The extent of hearth cooling is critically important in determining the feasible duration of an extended blast furnace maintenance shutdown. Based on a fixed domain method, a transient numerical mo...

Aiming at power plants denitrification system existing chimney entrance NOx concentration than denitrification system outlet NOx concentration of "upside down" phenomenon, adjust and optimize the test denitrification system, denitrification system NOx concentration distribution uniformity can be obviously improved after the adjustment, improve economy of denitration system operation. At the same time, the denitrification system operation suggestion.

As micro-grid technology's development, it has played an important role in improving the diversity and power quality of power supply. Micro-grid power supply planning is an important part of the micro-grid planning, the paper describes two different micro-grid power supply planning simulation logic, to provide some reference ideas for the micro-grid power supply planning simulation.

This paper establishes a power planning model based on minimization of the initial investment cost. The model includes the initial investment cost of wind turbines, photovoltaic cells, batteries, and biomass generators, diesel generators, power electronic devices and communications facilities in the objective function. In consideration of some constraint conditions, using the principle of priority of biomass generators, we use the particle swarm algorithm to solve the model. Through the calculation of actual examples, we simulate to find optimal solutions. Finally, we conclude that it should be possible to use biomass power generation and diesel generator power.

Power quality and power marketing are comprehensive concept contains multiple indexes. This paper builds the index system of the power quality promoting the power market development. And the structural equation modeling (SEM) be used to calculate the impact factor of power quality to marketing at different times and areas. This paper firstly puts power quality and marketing which are regarded as latent variables. And select the power quality index that includes the amplitude, frequency, spectrum, modulation, the notch depth and marketing index that includes market share, electricity consumption per capita, customer satisfaction rate, install electricity rate, customer loss rate as measured variables of latent variables, and establish the causal influence path graph of power quality and power marketing. According to the path graph, which reflecting causal relationships among the latent variables and the measurement equation reflecting relationship between the latent variable and significant variables. To test the significance and the rationality of the parameter and evaluate the overall performance of the structure equation model. Finally, according to the path graph and the path coefficient, we get causal influence coefficient between the power quality comprehensive index and power marketing comprehensive index.

The main objective of designing skin color model is to determine whether the pixel is skin color pixels and generate the skin color mask images. The paper discusses the choise of color space and skin color model designing in skin color detection system, analysis the problems often needed to solve in it and put forward an improved skin color detection algorithm model based on ellipse boundary. The skin color detection experiment is completed. The result of experiment shows the skin color detection algorithm model is good.

In this paper, the problem of high calcium carbonate content of desulfurization gypsum using limestone - gypsum wet desulphurization technology in coal-fired power plants questions, recommendations in running process from the control of absorption tower pH, lime stone powder, lime powder fineness activity to solve the above problems.

In this paper, the output can not meet the operating requirements problems of power plant desulfurization device wet mill system operation, site of the optimization test of wet mill system, optimization and adjustment, wet mill output and fineness of limestone reached or better than the design value, the operation time was shortened, and achieved good economic and social benefits. With reference to the same type of wet overflow type ball mill.

In the paper, a design and implementation of real-time video transport system based on MPC860T is introduced. The key technologies and system implementation steps are discussed from the hardware architecture and software design, focusing on the process of the hardware design and software platform composition. Finally, the operation process analysis of system platform is given. The test results show that the system can achieve better real-time performance and reliability.

This paper designs a kind of new electrolytic capacitor-less LED (light-emitting diode) driver, which converts the commercial ac voltage to a pulsating current with twice the line frequency driving high-brightness LEDs. As no electrolytic capacitor is used, this driver possesses the unique advantage of long lifetime to match with that of LEDs. A method of injecting the third and fifth harmonics into the input current to reduce the peak-to-average ratio of the output current is also proposed. A 25V, 0.35A output prototype is built and tested in the laboratory, and the experimental results are presented to verify the effectiveness of the electrolytic capacitor-less LED driver and its control method.

Based on the study of the maintaining of wet desulphurization installments in coal-fired power plant, similar problems have been found in maintaining process. including desulphurization absorption tower, mist eliminator, slurry circulating pump, gas duct, flue damper. The corresponding countermeasures have been proposed.

Moisture was one of the most important performances of the gypsum, but now there did not have effective way to judge the dewater character of gypsum slurry in the operation of desulfurization. In this article, the method of using settling velocity to deduce the dewater performance was proposed and experiments had been done to verify the feasibility, it would provide beneficial reference for the operation of flue gas desulfurization.

Wastewater treatment system was an important part of the wet desulfurization, and it played an important role to improve the quality of absorber slurry. Combined with the problems of desulfurization efficient reduced and moisture content in gypsum exceed normal, this paper pointed out the deficiencies which used the chlorine ion concentration to control the operation of desulfurization waster water; and suggested the influence of chlorine ion and the other impurities should be studied comprehensively, some guides for in-service supervision on the operation of FGD should be established as soon as possible.

In view of the DTV system demand, from the encryption digital television key production, the key protection, the key renewed the entire key management process which transmitted until the key to carry on the discussion, proposed with the commercial CAS different key management strategy, improved the key production and the renewal way, designed has been suitable for the above digital television decipherment scheme key management plan, through from produced the key the method to reduce the correspondence expenses effectively, might transmit under the limited band width most according to Pass through in the ground clear channel simulation transmission, the simulation result indicated that, this plan deciphers effect and the primitive sound/video frequency difference is not big, therefore this plan has the low mistake sensitivity. Through to the simulation result analysis, proved this article designs the decipherment scheme suits the DTTB system compared to wired environment under CAS.

Lime residuals left from water softening process reused as desulferizer in the coal-fired power plants has been reported. The active composition (CaO) is 43.06 %. 98.77% of lime residuals are particles smaller than 45 µm. The dissolution rate of lime residuals is higher than that of limestone. The results show that the reuse of lime residuals shall facilitate the absorbance of SO2 and enhance the efficiency of desulfurization. Additional corrosion of apparatus and pipes, the slurry bubble or overflow has not been observed during the experiment. The water consumption can be largely reduced, and the gypsum matches the reuse standard. Coal ashes and gypsum are concluded for many kinds of applications.

Desmoid tumors (DTs) are rare lesions that do not possess any metastatic potential. However, they have a strong tendency to invade locally and recur. They constitute 3% of all soft tissue tumors and 0.03% of all neoplasms. Abdominal DTs occur sporadically or are associated with certain familial syndromes, such as familial adenomatous polyposis (FAP). The single form of this neoplasm most frequently occurs in females of reproductive age and during pregnancy. A female patient with a DT of the abdominal wall who had no relevant family history was admitted to hospital. The patient, who presented with a painless mass in the left anterolateral abdomen, had no history of trauma, surgery or childbearing. According to the medical history, physical examination and CT report, the patient was diagnosed with DT. Radical resection of the affected abdominal wall musculature was performed, and the defect was replaced with a polypropylene mesh. The histological diagnosis was of DT. The patient remains in good health and complete remission without any other treatment following surgery. DTs exhibit aggressive growth and have a high rate of recurrence. Surgery is the optimal treatment, and subsequent radiotherapy may decrease the local recurrence rate. Further research into their aetiology is required combined with multicentre clinical trials of new treatments in order to improve management of this disease. This case report provides general knowledge of DT, and may be used as a guidance for diagnosis and treatment.

A mathematical model is proposed to describe gas–powder flow in a bed packed with particles. The model is the same as the two fluid model developed on the basis of the space-averaged theorem in terms of the governing equations but extended to consider the interactions between gas, powder and packed particles, as well as the static and dynamic holdups of powder. In particular, a method is proposed to determine the boundary between dynamic and stagnant zones with respect to powder phase, i.e., the profile of the powder accumulation zone. The validity of numerical modeling is confirmed by comparing the predicted and measured distributions of powder flow and accumulation under various flow conditions. On this basis, the role of gas–powder and powder–particle forces relative to the gravity force in controlling the powder flow and accumulation is analyzed.

To implement calibration transfer between Raman spectrometers, an improved piecewise direct standardization (PDS) is proposed in the present paper. Standard normal variate (SNV) is firstly introduced to reduce the influence of spectral background and intensity corresponding to the master spectrometer and the slave spectrometer; then PDS algorithm is used to eliminate the differences between Raman spectra for a specific sample. Moreover, a new quantitative criterion, called transfer error rate, is proposed to evaluate the performance of calibration model transfer. This improved PDS is applied to Raman spectral analysis of gasoline. The result shows that the proposed algorithm not only needs a small quantity of transfer samples, but also obtains high transfer accuracy and strong model robustness.