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Recently, the studies on the application of coral sand in concrete construction attracted wide attention, especially in China. Coral sand and coral sand powder (CSP) can be used as fine aggregate and mineral admixture in concrete, respectively. The main component of CSP is calcium carbonate (CaCO3), up to 96%. However, the utilization of CSP in cement mortar will cause performance degradation. Ground-Granulated Blast Furnace Slag (BFS) be used to improve the property of CSP-Portland cement mortar. In this study, the coral sand powder-blast furnace slag-Portland cement (CSP-BFS-PC) ternary system had been used to produce cement paste and mortar. The hydration product of the CSP-BFS-PC ternary system are researched fundamentally by X-ray diffraction, and compressive strength are tested at different curing age. The results show that CSP can suppress consumption of C3A. 15wt.% BFS can offset the strength loss of cement mortar due to the substitution of CSP for cement (CSP less than 15wt.%), especially 7-28 days.

It remains a big challenge to develop non-precious metal catalysts for oxygen evolution reaction (OER) in energy storage and conversion systems. Herein, a facile and cost-effective strategy is employed to in situ prepare the Ni/Fe oxyhydroxide anchored on nitrogen-doped carbon aerogel (NiFeOx(OH)y@NCA) for OER electrocatalysis. The as-prepared electrocatalyst displays a typical aerogel porous structure composed of interconnected nanoparticles with a large BET specific surface area of 231.16 m2·g−1. In addition, the resulting NiFeOx(OH)y@NCA exhibits excellent OER performance with a low overpotential of 304 mV at 10 mA·cm−2, a small Tafel slope of 72 mV·dec−1, and excellent stability after 2000 CV cycles, which is superior to the commercial RuO2 catalyst. The much enhanced OER performance is mainly derived from the abundant active sites, the high electrical conductivity of the Ni/Fe oxyhydroxide, and the efficient electronic transfer of the NCA structure. Density functional theory (DFT) calculations reveal that the introduction of the NCA regulates the surface electronic structure of Ni/Fe oxyhydroxide and increases the binding energy of intermediates as indicated by the d-band center theory. This work provides a new method for the construction of advanced aerogel-based materials for energy conversion and storage.

RORγ is a dual-functional drug target, which involves not only induction of inflammation but also promotion of cancer immunity. The development of agonists of RORγ promoting Th17 cell differentiation could provide a novel mechanism of action (MOA) as an immune-activating anticancer agent. Herein, we describe new 2-(ortho-substituted benzyl)-indole derivatives as RORγ agonists by scaffold hopping based on clinical RORγ antagonist VTP-43742. Interestingly, subtle structural differences of the compounds led to the opposite biological MOA. After rational optimization for structure-activity relationship and pharmacokinetic profile, we identified a potent RORγ agonist compound 17 that was able to induce the production of IL-17 and IFNγ in tumor tissues and elicit antitumor efficacy in MC38 syngeneic mouse colorectal tumor model. This is the first comprehensive work to demonstrate the in vivo antitumor efficacy of an RORγ agonist.

Alumina (Al2O3)-based diphasic aerogels have better physical properties than those of pure Al2O3 aerogel according to previous studies. In the present research, we focused on an alumina–titania (Al2O3-TiO2) diphasic aerogel. A series of Al2O3 aerogels were synthesized and studied with and without minor TiO2 dopants (up to 10 mol%). We found that the pure Al2O3 aerogel, which had the fiber-like particles, was stronger than those with TiO2 dopants that possessed the sphere-like particles. However, the sphere-like particles make the TiO2-doped Al2O3 aerogel (with 3 mol% TiO2) possessing the largest specific surface area (SSA) of 650 m2/g, much larger than that of the pure Al2O3 aerogel (326 m2/g). This work proved that fiber-like particles enhance strength but reduce SSA of Al2O3 aerogel. At last, ceramic fibers reinforced Al2O3 aerogel composites with the sizes of 20 cm width × 20 cm length × 1 cm thickness were fabricated. The aerogel composites possessed a thermal conductivity of 0.136 W/m K at 1000 °C, better than those of the ceramic fiber blankets itself (0.30 W/m K), indicating potential application as high-temperature thermal insulator.

Wind power is playing an increasingly critical role in new energy sources. In order to modify the precision of short-term wind power prediction, this thesis proposes a combined model for short-term wind power prognosticate based on Complete Ensemble Empirical Mode Decomposition of Adaptive Noise (CEEMDAN), Time Pattern Attention mechanism (TPA), Time Convolution Network (TCN) and Multi-strategy Manta Ray Foraging Optimization (MRFO). Firstly, this thesis uses CEEMDAN algorithm decompose the wind power sequence, and obtain the sub-sequence components. Combined with key meteorological variable data, this thesis constructs a training set. Then, it optimizes the convolutional network hyperparameters with MRFO. Finally, the final forecasting value is obtained after reconstructing the forecasting results by predicting sub-sequence components respectively with TPA and TCN. The practical cases reveal that the propound combined forecasting model can better predict the wind power change trend. Compared with other methods, this model can significantly improve the short-term presaging accuracy of wind power.

The utilization of coral waste is an economical way of using concrete in coastal and offshore constructions. Coral waste with more than 96% CaCO3 can be ground to fines and combined with supplementary cementitious materials (SCMs) such as fly ash, silica fume, granulated blast furnace slag in replacing Portland cement to promote the properties of cement concrete. The effects of coral sand powder (CSP) compared to limestone powder (LSP) blended with SCMs on hydration and microstructure of mortar were investigated. The result shows CSP has higher activity than LSP when participating in the chemical reaction. The chemical effect among CSP, SCMs, and ordinary Portland cement (OPC) results in the appearance of the third hydration peak, facilitating the production of carboaluminate. CSP-SCMs mortar has smaller interconnected pores on account of the porous character of CSP as well as the filler and chemical effect. The dilution effect of CSP leads to the reduction of compressive strength of OPC-CSP and OPC-CSP-SCMs mortars. The synergic effects of CSP with slag and silica fume facilitate the development of compressive strength and lead to a compacted isolation and transfer zone (ITZ) in mortar.

The hydration kinetics of Portland cement with and without nano-SiO₂ (NS) were evaluated via isothermal calorimetry and investigated based on the mathematic method of the Krstulovic-Dabic model in this paper. NS was used to substitute Portland cement at 0, 1 and 3 wt.% by mass. The test results obtained in this study indicated that the hydration process of Portland cement was dramatically promoted in terms of increasing the heat released and the heat release rate when NS was added. From the Krstulovic-Dabic model, the dynamics process of Portland cement was controlled by nucleation and crystal growth (NG), phase boundary interactions (I) and the diffusion (D) process, it does not matter whether there was NS or not, but the transformation of the controlling process occurred at a lower hydration degree for the NS-added pastes. Moreover, the increase in NS content increased the values of the kinetics parameters KNG and KI, but decreased KD and the reaction exponent to a different degree.

Numerical modeling has been widely used to simulate the heat transfer of ground heat exchanger (GHE), However, there is a lack of analysis and comparison of different models and methods, for helix energy pile, there is a lack of an efficient and accurate numerical model to study the complex heat transfer problems. In this paper, taking a novel truncated cone helix energy pile (CoHEP) as the object, a two-dimensional(2-D) equivalent heat conduction model considering the heat transfer characteristics of the heat convection in the buried pipe was established, at the same time, a three-dimensional(3-D) full scale model and a 2-D ring coils model were established. By comparing the simulation results of three numerical models with the experimental results under the same conditions, the effects and suggestions of meshing on different models, the model characteristics and main error sources of different models were analyzed. The long-term and short-term simulation results and temperature distribution characteristics of different models were further analyzed. The study shows that the 3-D model has the highest accuracy in the simulation process, but the simulation efficiency is low, and it is easy to be affected by meshing. The 2-D ring coils model has high simulation efficiency, but the long-term simulation error is large, and the thermal influence radius of the pipe is smaller than the actual situation. For the 2-D equivalent model, the simulation error is small, and the thermal influence radius is close to those of the 3-D full scale model, and the effect of long-term simulation is obviously better than that of the 2-D ring coils model. The results indicate that the 2-D equivalent model effectively improves the simulation accuracy of the 2-D heat conduction numerical model, it can obtain the temperature distribution inside and outside the buried pipe which is closer to the actual situation with less calculation and higher simulation accuracy.

Compressed sensing (CS) as an efficient means has been widely applied in magnetic resonance imaging (MRI). As a regularization term to enforce the sparsity in the finite difference domain, the conventional total variation (TV) has been introduced in this field, where the staircase effect is presented. To overcome this issue, a new framework in the difference domain called joint constraint patch-based total variation (JCTV) is proposed. First, the image patch is utilized as the unit for TV norm to improve the adaptativity. Second, JCTV introduces a new nonlocal constraint term that exploits the estimated coefficients of the fully sampled image via linear minimum mean square error (LMMSE) criterion to improve the reconstruction performance. Finally, an alternative minimization algorithm is developed to seek the solution. Extensive experiments on a set of in vivo MR images demonstrate that the proposed algorithm outperforms the state-of-the-art approaches in terms of peak signal-to-noise ratio and visual quality.

3GPP LTE, or Long Term Evolution, the fourth generation wireless access technology, is being rolled out by many operators worldwide. Since LTE Release 10, network densification using small cells has been an important evolution direction in 3GPP to provide the necessary means to accommodate the anticipated huge traffic growth, especially for hotspot areas. Recently, LTE Release 12 has been started with more focus on small cell enhancements. This article provides the design principles and introduces the ongoing discussions on small cell enhancements in LTE Release 12, and provides views from two active operators in this area, CMCC and NTT DOCOMO.

A novel series of pyrazolo[3,4-c]isoquinoline derivatives was discovered as B-Raf(V600E) inhibitors through scaffold hopping based on a literature lead PLX4720. Further SAR exploration and optimization led to the discovery of potent B-Raf(V600E) inhibitors with good oral bioavailability in rats and dogs. One of the compounds EBI-907 (13g) demonstrated excellent in vivo efficacy in B-Raf(V600E) dependent Colo-205 tumor xenograft models in mouse and is under preclinical studies for the treatment of melanoma and B-Raf(V600E) associated cancers.

Indoor coverage is essential to the mobile user experience, because the signal power from the remote macro base stations is seriously weakened after penetrating the walls. Traditional indoor coverage system is a good solution but it can not be deployed in all the buildings. In order to enhance the received signal power inside the building, a relay can be used in a long term evolution (LTE) system. The benefits of relay are: it can be deployed anywhere quite near to the building since it uses wireless backhaul with less position limitation, and thus it can amplify the transmitting power due to the nearby position to the building comparing to the remote macro base stations. Then even with penetration loss, the received signal power inside the building is still high enough to carry traffic. The field test results show that a TD-LTE relay can improve the indoor received signal power and traffic obviously, and thus it's a good solution to enhance outdoor to indoor coverage.

Alkali-activated slag cement (AASC) was studied as a host matrix for the immobilization of simulated high-level wastes. Experimental results show that, with a waste loading as high as 25%, AASC waste form presents high compressive strength (65--100 MPa), low porosity (less than 10%) and low leach rates (10{sup {minus}5} and 10{sup {minus}6} g/cm{sup 2}d for Cs and Sr, respectively). The mechanism of encapsulation of nuclides in AASC waste form was also studied.

Calculates the envelope thermal characteristics of the Phase Change Material (PCM) lightweight building fabrics, such as the thermal inertia index, storage heat coefficient, delay time and attenuation ratio,ect. Comparing with the common lightweight building fabric the envelope thermal characteristics of the PCM lightweight building fabrics has been improved preferably. The thermal inertia index, attenuation ratio and delay time of PCM components are respectively the 3.75,14 and 10 times as the one of the common building fabrics. So, it will be less cooling load in the PCM lightweight building than the common lightweight building. Then combining the nighttime ventilation we carries through the contrast experiments between light weight PCM wall and ordinary building in chongqing summer, the results show that the electricity consumption in light weight PCM wall room be 32.5% less than the one in ordinary room, the results also show that outdoor temperature have great effect on the energy efficiency.

To master the heat transfer rule of phase change material(PCM) wall, two kinds of hollow boxes was made with different material, one was made of pure EPS granule，the other one was made of EPS and PCM, temperature of cavum was measured during thermal translation process experiment. The hollow boxes was separated into 4 nodes finite element, the experiment time was divided into finite time point, the diathermanous process of boxes was simulated by finite element software system. The result indicated that simulation process by computer was inosculated with experiment, there was obvious temperature flateform during heat transfer of PCM wall, duration of different direction of phase change process was different, during ascendant process and descent process, change rate and distributing characteristic were contrary on the two sides of phase change point temperature.

Alkali-activated slag cement (AASC) was studied as a matrix for immobilization of radioactive wastes. Experimental results show that AASC is the best among the other cements studied, and that AASC based waste forms have high strength, low porosity, high resistance to chemical corrosion and to heat, and low solubility as well as leachability.

In this paper, the impact of diversity order on symbol error rate (SER) performance is investigated for the cooperative amplify-and-forward (AF) multiple-input-and-multiple-output (MIMO) relaying system under the average power scaling (APS) constraints. Furthermore, the optimal power allocation (OPA) scheme is proposed based on the criterion of maximizing signal-to-noise-ratio (SNR). Through the SER analysis and numerical results, it can be shown that the diversity order in AF MIMO relaying system under APS is MT (the number of transmitting antennas) when uniform power allocation (UPA) is adopted. Given MR receiving antennas at the relay nodes, the proposed novel OPA scheme can not only reduce the SER but also improve the diversity order efficiently up to MR even when MT = 1.

Relay is emerged recently as a promising solution not only to improve coverage but also end-to-end date rate. How to manage the radio resources effectively for the integrated cellular network are the key issues to be studied. The paper re-evaluates the traditional concept of adjustment and optimization for the call routing and congestion control as call routing and admission control (CRAC). With respect to the mobility and the variable wireless environment, the call re-routing algorithm which implements the intelligence and adaptability is also studied as call re-routing control (CRRC). The joint routing and re-routing control (JoRR) algorithm is proposed to realizes the global optimization of the existing algorithms Two schemes, namely Centralized Architecture (CA) and Decentralized Architecture (DA), are studied to implement the JoRR algorithm whose criterion is selected by considering the characteristics of the integrated cellular system and the tradeoff between the cost and the effectivity. At last, a set of system-level performance evaluation is provided based on the characteristics of the new network architecture.

In future wireless communication systems, an architecture introducing wireless relaying technologies into the cellular infrastructure, seems a promising approach to enlarge the coverage area and enhance system capacity. How to design an efficient call admission control algorithm to perform routing and channel allocation for such integrated cellular system, and manage the radio resources effectively are the key issues to be studied. Based on time division multiple access (TDMA) scheme, this paper proposes a novel call routing and admission control (CRAC) algorithm for the two-hop cellular system with the aim of extending system coverage and increasing system capacity cost-effectively. With the proposed CRAC algorithm, a mobile terminal (MT) can choose the conventional direct link or opt for the relaying considering the transmission quality as well as the traffic load balance. The simulation results show that the CRAC algorithm can decrease the blocking probability significantly and increase the system capacity and enhance the coverage by utilizing the limited channel resource efficiently. Keywords-Relaying, Call routing and admission control (CRAC), Cellular

The multiple input multiple output (MIMO) system is a huge reform to future wireless communication systems. The proposed MIMO-based virtual group cell structure is a novel cellular construction method, which is suitable for new advanced physical techniques. However, existing radio resource management algorithms are not suitable for multiple antenna environments. The paper improves the traditional admission control algorithm and makes it suitable for MIMO systems. According to the characteristics of the new network architecture, a different interference distribution model is provided to help evaluate the system performance.

A novel clinker with low Ca/Si ratio and low sintering temperature was synthesized, and the property of the clinker was tested. A clinker sintered from industrial raw materials mainly contains rankinite (Ca3Si2O7), pseudowollastonite (Ca-3(Si3O9)) and ferrosilite ((Ca,Mg,Fe,Al)(2)Si2O6). Quantitative analysis of the mineral composition was performed via X-ray powder diffraction using the Rietveld method. Results showed that the optimal formation region of the clinker was at 1300 degrees C for 4 h, resulting in a Ca/Si ratio of 1.27 and 72.7% rankinite, 24.6% pseudowollastonite and 2.7% ferrosilite. The hardening of the clinker occurred mainly due to the carbonation of rankinite and pseudowollastonite yielding CaCO3 and SiO2. Carbonation depth was determined using confocal laser scanning microscopy (CLSM). Experiments indicated that the carbonation depths of the clinker in accelerated carbonation conditions were 659 +/- 20 mu m, 787 +/- 18 mu m and 1118 +/- 98 mu m for 1, 3, and 28 days of carbonation, respectively. Moreover, well-developed calcite crystals could form a network-like and interconnected structure, further enhancing its performance. (C) 2016 Elsevier Ltd. All rights reserved.

This paper presents the hydration kinetics, products and microstructure of an alite-ye'elimite clinker containing 4 wt% of ye'elimite to boost the early strength development. Isothermal calorimetry, X-ray diffraction, backscattered scanning electron microscopy and mercury intrusion porosimetry were used to study the hydration processes. The results showed that the ye'elimite phase hydrated very rapidly, before the main hydration of alite, forming ettringite as main hydration product. The ye'elimite hydration products precipitated throughout the pore space and reduced the microporosity of the hardened paste at early age. The presence of ye'elimite strongly affected the early hydration before 24 h of hydration, but did not show a significant effect on the hydration kinetics or products at later ages. (C) 2020 Elsevier Ltd. All rights reserved.

Modeling of the kinetics of the synthesis process for calcium sulfate alpha-hemihydrate from gypsum formed by flue gas desulfurization (FGD) is important to produce high-performance products with minimal costs and production cycles under hydrothermal conditions. In this study, a model was established by horizontally translating the obtained crystal size distribution (CSD) to the CSD of the stable phase during the transformation process. A simple method was used to obtain the nucleation and growth rates. A nonlinear optimization algorithm method was employed to determine the kinetic parameters. The model can be successfully used to analyze the transformation kinetics of FGD gypsum to alpha-hemihydrate in an isothermal batch crystallizer. The results showed that the transformation temperature and stirring speed exhibit a significant influence on the crystal growth and nucleation rates of alpha-hemihydrate, thus altering the transformation time and CSD of the final products. The characteristics obtained by the proposed model can potentially be used in the production of alpha-hemihydrate.