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Excellent performance of refractories in blast furnace hearth is one of the important factors to ensure longevity of blast furnaces. As an emerging refractory for application in blast furnace, alumina-carbon composite brick combines the superior properties of carbon and alumina. Firstly, the thermal conductivity of alumina-carbon composite brick was measured by the laser flash method and the new device method to verify the feasibility of the new device method for thermal conductivity measurement. Secondly, the influence of heating temperature of the heating furnace and cooling water flow on the thermal conductivity of the alumina-carbon composite brick, and the comparison of the thermal conductivity of carbon brick, alumina-carbon composite brick and corundum brick were investigated to confirm the heat transfer mechanism of alumina-carbon composite brick. High thermal conductivity and erosion resistance to slag and hot metal of the alumina-carbon composite brick are consequent from: (a) reasonable composition combination of Al2O3, C, SiO2, SiC, etc., (b) dense structure, small pore diameter, and uniform distribution of the pores, (c) the generated SiC whiskers and Al6Si2O13, which can fill in the pores and reduce the porosity. Finally, the analysis on the phase distribution of the alumina-carbon composite brick in a dissected blast furnace was performed to illustrate the relationship between the erosion resistance and the thermal conductivity of alumina-carbon composite brick.

The corrosion behaviors of corundum brick and carbon composite brick used in blast furnace hearth by CaO-SiO2-MgO-Al2O3-Cr2O3(-CaF2) slags were studied in the present work. The degradation of the corundum brick in slag was a result of slag infiltration and brick dissolution, and the corrosion of the brick became more serious with the addition of CaF2 due to the decrease of slag viscosity. The disintegration of carbon composite brick in CaF2-containing slag was caused by the combination of slag penetration, brick dissolution and reaction between slag and brick. By comparing the corrosion behavior in CaF2-containing slag between the corundum brick and carbon composite brick, the corrosion degree of the corundum brick was greater than that of the carbon composite brick. To the blast furnace operation in which a low grade iron ore such as laterite ore and CaF2 containing slag (about 2 wt%) are used, it was found that the carbon composite brick with better slag corrosion resistance can be selected as a hearth refractory so as to improve the operation performance and ensure the longer campaign life of blast furnace.

The elastic and inexpensive computing resources such as clouds have been recognized as a useful solution to analyzing massive human genomic data (e.g., acquired by using next-generation sequencers) in biomedical researches. However, outsourcing human genome computation to public or commercial clouds was hindered due to privacy concerns: even a small number of human genome sequences contain sufficient information for identifying the donor of the genomic data. This issue cannot be directly addressed by existing security and cryptographic techniques (such as homomorphic encryption), because they are too heavyweight to carry out practical genome computation tasks on massive data. In this article, we present a secure algorithm to accomplish the read mapping, one of the most basic tasks in human genomic data analysis based on a hybrid cloud computing model. Comparing with the existing approaches, our algorithm delegates most computation to the public cloud, while only performing encryption and decryption on the private cloud, and thus makes the maximum use of the computing resource of the public cloud. Furthermore, our algorithm reports similar results as the nonsecure read mapping algorithms, including the alignment between reads and the reference genome, which can be directly used in the downstream analysis such as the inference of genomic variations. We implemented the algorithm in C++ and Python on a hybrid cloud system, in which the public cloud uses an Apache Spark system.

The corrosion behavior of carbon composite brick used in blast furnace hearth by CaO-SiO 2 -MgO-Al 2 O 3 -Cr 2 O 3 -based slag with and without B 2 O 3 at different rotation speeds and temperatures was investigated in this work. The radius decrement of the brick increased with the increase of rotation speed, temperature and content of B 2 O 3 in slag. Furthermore, the square of the radius decrement of brick changed linearly with the immersion time, indicating that the dissolution of the brick into slag may be controlled by the mass diffusion step. A slag penetration layer or product layer may be firstly formed during the corrosion process of carbon composite brick in slags, and then the components of brick dissolved into the molten slag by diffusing through this layer. The corrosion of the carbon composite brick by B 2 O 3 -containing slag is much severer than that by slag without B 2 O 3 due to the lower viscosity and melting temperature of B 2 O 3 -containing slag.

Al2O3–SiC–SiO2–C composites are widely used in ironmaking operations due to their favorable erosion-resistance. In the present paper, the oxidation behavior and kinetics of Al2O3–SiC–SiO2–C composites in air are investigated in terms of a theoretical analysis associated with the experimental data. Furthermore, the effects of temperature on the oxidation reaction are discussed. The results show that the oxidation of Al2O3–SiC–SiO2–C composites is mainly caused by atmospheric oxygen reacting with C and SiC in the materials. At 1200 °C, a protective layer can be found on the material surface due to the formation of the mullite phase. Predictions from the Chou model are in agreement with the experimental data. The characteristic oxidation time which indicates anti-oxidation properties for Al2O3–SiC–SiO2–C composites at 1000 °C and 1200 °C are 142.41 min and 264.89 min, respectively, indicating that the material at 1200 °C is more resistant to oxidation due to the formation of a protective layer on the surface.

Oxidation of carbon is one of the main problems in alumina–carbon based refractory. In this paper, the oxidation behaviors of novel carbon composite brick and traditional carbon brick were investigated by non-isothermal and isothermal experiments, and the samples after oxidation were examined by SEM and EDS analysis. The results show that the oxidation resistance of carbon composite brick is better than that of carbon brick. At 800−1200 °C, the oxidation kinetics of carbon brick follows the linear rate law, which belongs to non-protective oxidation, and the oxidation activation is 5586.76 J/mol. However, the oxidation kinetics of carbon composite brick follows the parabolic rate law, which belongs to protective oxidation. The compressive strength decreases with the increasing mass loss after oxidation due to the carbon loss, so for carbon composite brick which has less content of carbon the oxidation resistance is better than that of carbon brick. Furthermore, the existence of SiC in the surface of carbon composite brick is another reason for its good oxidation resistance.

Objective To propose a new approach to privacy preserving data selection, which helps the data users access human genomic datasets efficiently without undermining patients’ privacy. Methods Our idea is to let each data owner publish a set of differentially-private pilot data, on which a data user can test-run arbitrary association-test algorithms, including those not known to the data owner a priori. We developed a suite of new techniques, including a pilot-data generation approach that leverages the linkage disequilibrium in the human genome to preserve both the utility of the data and the privacy of the patients, and a utility evaluation method that helps the user assess the value of the real data from its pilot version with high confidence. Results We evaluated our approach on real human genomic data using four popular association tests. Our study shows that the proposed approach can help data users make the right choices in most cases. Conclusions Even though the pilot data cannot be directly used for scientific discovery, it provides a useful indication of which datasets are more likely to be useful to data users, who can therefore approach the appropriate data owners to gain access to the data.

The Global Alliance for Genomics and Health (GA4GH) created the Beacon Project as a means of testing the willingness of data holders to share genetic data in the simplest technical context—a query for the presence of a specified nucleotide at a given position within a chromosome. Each participating site (or “beacon”) is responsible for assuring that genomic data are exposed through the Beacon service only with the permission of the individual to whom the data pertains and in accordance with the GA4GH policy and standards. While recognizing the inference risks associated with large-scale data aggregation, and the fact that some beacons contain sensitive phenotypic associations that increase privacy risk, the GA4GH adjudged the risk of re-identification based on the binary yes/no allele-presence query responses as acceptable. However, recent work demonstrated that, given a beacon with specific characteristics (including relatively small sample size and an adversary who possesses an individual’s whole genome sequence), the individual’s membership in a beacon can be inferred through repeated queries for variants present in the individual’s genome. In this paper, we propose three practical strategies for reducing re-identification risks in beacons. The first two strategies manipulate the beacon such that the presence of rare alleles is obscured; the third strategy budgets the number of accesses per user for each individual genome. Using a beacon containing data from the 1000 Genomes Project, we demonstrate that the proposed strategies can effectively reduce re-identification risk in beacon-like datasets.

Traditional refractory materials for blast furnace hearth lining are mainly composed of carbon bricks and the ceramic cup. However, these materials can’t meet the demands for long service life design of blast furnaces. In this paper, a new refractory called carbon composite brick (CCB) was introduced, which combined the advantages of carbon bricks and the ceramic cup. In this case, the resistance of the CCB against corrosion was equal to the ceramic cup and the thermal conductivity of the CCB was equal to carbon bricks. From the results of more than 20 blast furnaces, the CCB could be well used in small blast furnaces and large blast furnaces. In the bad condition of low grade burden and high smelting intensity, the CCB gave full play to the role of cooling system, and effectively resisted the erosion of hot metal to improve the service life of blast furnaces.

The carbon composite brick is a new refractory used in blast furnace hearth and bottom. It caused wide attention due to its high thermal conductivity and low erosion by molten iron. In this paper, chemical constituents, SEM-EDS and X-ray diffraction were carried out in order to understand reaction mechanisms. A series of experiments of oxidation resistance characteristics were made. The oxidation mechanisms of carbon composite bricks in the presence of air were analyzed. According to the analysis on many experimental results, the oxidation process of carbon composite bricks under different temperatures were controlled by different mechanisms. In the condition of high temperature, SiO2 as oxidation product hindered the diffusion of O2, and reduced the oxidation loss of graphite in the internal.

To answer the need for the rigorous protection of biomedical data, we organized the Critical Assessment of Data Privacy and Protection initiative as a community effort to evaluate privacy-preserving dissemination techniques for biomedical data. We focused on the challenge of sharing aggregate human genomic data (e.g., allele frequencies) in a way that preserves the privacy of the data donors, without undermining the utility of genome-wide association studies (GWAS) or impeding their dissemination. Specifically, we designed two problems for disseminating the raw data and the analysis outcome, respectively, based on publicly available data from HapMap and from the Personal Genome Project. A total of six teams participated in the challenges. The final results were presented at a workshop of the iDASH (integrating Data for Analysis, 'anonymization,' and SHaring) National Center for Biomedical Computing. We report the results of the challenge and our findings about the current genome privacy protection techniques.

Summary: With the wide application of next-generation sequencing (NGS) techniques, fast tools for protein similarity search that scale well to large query datasets and large databases are highly desirable. In a previous work, we developed RAPSearch, an algorithm that achieved a ~20–90-fold speedup relative to BLAST while still achieving similar levels of sensitivity for short protein fragments derived from NGS data. RAPSearch, however, requires a substantial memory footprint to identify alignment seeds, due to its use of a suffix array data structure. Here we present RAPSearch2, a new memory-efficient implementation of the RAPSearch algorithm that uses a collision-free hash table to index a similarity search database. The utilization of an optimized data structure further speeds up the similarity search—another 2–3 times. We also implemented multi-threading in RAPSearch2, and the multi-thread modes achieve significant acceleration (e.g. 3.5X for 4-thread mode). RAPSearch2 requires up to 2G memory when running in single thread mode, or up to 3.5G memory when running in 4-thread mode. Availability and implementation: Implemented in C++, the source code is freely available for download at the RAPSearch2 website: http://omics.informatics.indiana.edu/mg/RAPSearch2/. Contact: ude.anaidni@eyy Supplementary information: Available at the RAPSearch2 website.