Search

In order to solve the cost and environmental pollution problems caused by the transportation and stacking of shield tunneling muck, and to achieve the goal of resource reutilization of solid waste, a study was conducted based on a section of the Zhengzhou Metro Line 10 shield tunneling project. Excavated muck was used to replace sand, fly ash, and bentonite, while rice husk ash (RHA) was used to partially replace cement in the preparation of micro expansion synchronous grouting material. The effects of RHA content, muck particle size, water-binder ratio, and the type and content of expansion agents on the working and mechanical properties of synchronous grouting material were investigated. The results indicate that RHA significantly affects the slurry consistency and setting time, and higher RHA content leads to lower slurry consistency and shorter setting time. When RHA content is 25% (based on mass ratio of cement), the slurry consistency decreases by 27. 5% and the setting time shortens by 39. 9%. As RHA content increases, the compressive strength of slurry decreases first and then increases. As the particle size of muck increases, the slurry consistency and setting time decrease. Quicklime powder and high soundless static cracking agent (HSCA) as expansion agents reduce slurry consistency but effectively improve setting time and compressive strength. When HSCA mass fraction exceeds 3%, the expansion effect of HSCA is superior to that of quicklime powder. The tests determine that a water-binder ratio of 2.6, RHA content of 25%, adding larger particle size of muck, and the appropriate addition of expansion agents collectively meet all engineering requirements for slurry indicators, thereby providing a novel approach for the reutilization of shield tunneling muck and rice husk ash. [ABSTRACT FROM AUTHOR]

Based on the orthogonal test design method, the expansive mudstone in the cutting of Jingxin expressway in Zhangjiakou city was tested, and the relationship between the expansion rate of mudstone samples under different overlying loads and the soaking time, initial water content and compaction degree was studied, and the sensitivity of various factors was analyzed by the range analysis method. The results showed that the curve of expansion rate with the soaking time presented an S-shaped trend, which can be roughly divided into initial expansion stage, accelerated expansion stage and slow expansion stage. Under the same initial water content, the expansion rate increased with the increase of the compaction degree. Under the same compaction degree, the expansion rate decreased with the increase of initial water content. The range analysis method showed that the soaking time of the sample was the main factor affecting the expansion rate. Water content and compaction degree were the secondary influencing factors, and the influence of water content on the sample expansion rate was obvious under small load, and the load continued to increase, the compaction degree exceeded the influence of water content on the sample expansion rate. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The physicochemical properties of steel slag were investigated using SEM and IR, and it was found that free calcium oxide and free magnesium oxide in steel slag produce calcium hydroxide when in contact with water, leading to volume expansion. Thus, the expansion rate of steel slag itself was first investigated, and it was found that the volume expansion of steel slag was more obvious in seven days after water immersion. Then, the cement dosages of 5% and 6% of the steel slag expansion rate and cement-stabilized gravel volume changes between the intrinsic link were further explored after the study found that the cement bonding effect can be partially inhibited due to the volume of expansion caused by the steel slag, so it can be seen that increasing the dosage of cement can reduce the volume expansion of steel slag cement-stabilized gravel with the same dosage of steel slag. Finally, a prediction model of the expansion rate of steel slag cement-stabilized gravel based on the BP (back propagation) neural network was established, which was verified to be a reliable basis for predicting the expansion rate of steel slag cement-stabilized aggregates and improving the accuracy of the proportioning design. [ABSTRACT FROM AUTHOR]

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract It has been widely acknowledged that traditional packers will lose their elastic performance in the context of long periods of operation due to plastic deformation. This paper will introduce a swellable packer that can reduce the failure cases of production effectively. The deformation of the packer rubber in different media and temperatures has been analyzed. The pressure test of several packer rubber under different media is carried out in this paper. The reasonable expansion clearance between the rubber tube and the well wall is obtained by strength calculation to ensure the sealing reliability of the packer. Finally, the thermomechanical coupling calculation of the packer with different structural sizes is carried out. Experiments at different temperatures show that the higher saline concentration is associated with a lower expansion rate and a larger expansion rate in clear water. At the same time, the expansion of volume in clear water increases. In addition, the higher the external temperature is, the larger the temperature gradient is. When the temperature of the outer ring is between 100°C and 140°C, the internal temperature rises to 37°C under the thermomechanical coupling effect.

During the continuous multi-layer paving and rolling of core wall asphalt concrete in a high-temperature environment, the base layer of asphalt concrete cools down slowly, which seriously affects the continuity of construction. In order to demonstrate the feasibility of continuous multi-layer rolling construction of core walls, combined with the construction site rolling tests of asphalt concrete core wall of Qiaolabula Reservoir, the compactness and lateral expansion deformation law of core wall after continuous paving and rolling were studied. The results show that the porosity of continuous rolling asphalt concrete can be controlled within 3% when the temperature of base asphalt concrete is reduced to 100 ℃. The continuous paving and rolling of the core wall exhibits a certain amount of lateral expansion deformation, and the higher the temperature of the base asphalt concrete, the more obvious the secondary lateral expansion caused by the recompression of base asphalt concrete is when the upper layer is rolled. When the temperature of base asphalt concrete is controlled below 100 ℃, the lateral expansion rate of continuous three-layer paving and rolling does not increase significantly. [ABSTRACT FROM AUTHOR]

The surface morphology of mature biofilms is heterogeneous and can be divided into concentric rings wrinkles (I), labyrinthine networks wrinkles (II), radial ridges wrinkles (III), and branches wrinkles (IV), according to surface wrinkle structure and distribution characteristics. Due to the wrinkle structures, channels are formed between the biofilm and substrate and transport nutrients, water, metabolic products, etc. We find that expansion rate variations of biofilms growing on substrates with high and low agar concentrations (1.5, 2.0, 2.5 wt.%) are not in the same phase. In the first 3 days' growth, the interaction stress between biofilm and each agar substrate increases, which makes the biofilm expansion rate decreases before wrinkle pattern IV (branches) comes up. After 3 days, in the later growth stage after wrinkle pattern IV appears, the biofilm has larger expansion rate growing on 2.0 wt.% agar concentration, which has the larger wrinkle distance in wrinkle pattern IV reducing energy consumption. Our study shows that the stiff substrate does not always inhibit the biofilm expansion, although it does in the earlier stage; after that, mature biofilms acquire larger expansion rate by adjusting the growth mode through the wrinkle evolution even in nutrient extremely depletion. [ABSTRACT FROM AUTHOR]

Fundamental research on detonation is relevant to industrial safety issues, propulsion and energy production applications, and internal combustion engines. Detonation waves are intrinsically unsteady and may rapidly decelerate under certain circumstances. Fluid elements traveling behind these waves can undergo strong gas dynamical volumetric expansion, which can ultimately lead to quenching. More generally, critical ignition in expanding media results from the competition between expansion and chemical energy release. While the pioneering work by Lundstrom and Oppenheim investigated the role of unsteadiness on detonation dynamics both experimentally and numerically, studies on ignition quenching by the volumetric expansion mechanism has been essentially limited to theoretical and numerical approaches. Studies have converged towards the concept of critical decay rate (CDR), and of critical Damköhler number. The CDR theory incorporates the ignition delay-time and the characteristic time of shock speed decay for identifying the threshold for successful ignition, while the Damköhler number is defined as the ratio of characteristic expansion time over characteristic chemical time. While the majority of early studies only considered globalized reaction models and investigated mixtures with a single step of heat release, more recent studies have employed detailed chemical mechanisms and included mixtures with non-monotonous energy release profiles. Practical consequences of ignition in expanding media under conditions relevant to water hammer, high-pressure hydrogen jet, and deflagration to detonation transition in obstructed channels are also summarized. [ABSTRACT FROM AUTHOR]

The aim of this experiment is to investigate the effect of extrusion expansion on the physical properties and protein fraction of soybean protein concentrate. A compound feed made from soybean protein concentrate, wheat starch and phospholipids with primary puffing, followed by secondary puffing of a portion of the feed. The results showed that the alcohol soluble protein, albumin and gluten content of the feed were significantly reduced in the secondary expansion (P<0.05). However, the globular protein content of the feed from the secondary expansion was not significantly different from that of the primary expansion (P>0.05). The expansion rate of the second expansion was significantly lower than the expansion rate of the primary expansion (P<0.05). The solubility of the second expansion was significantly lower than the solubility of the primary expansion (P<0.05). There were no significant differences in feed capacity, softening time or water absorption (P>0.05). Under the present experimental conditions, primary puffing is more effective than secondary puffing. A single ouffing gives better use of the protein fraction content and properties of the feed, with a high swelling rate and improved stability in the water column. [ABSTRACT FROM AUTHOR]

The catalytic cracking of vacuum gas oil, as well as its mixture with tar deasphalted oil, the decaying molecules of which form correlated ions in the singlet state, has been studied. Under the influence of a magnetic field, a transition of ions from a singlet state to one of the triplet states is observed. The probability of recombination of diffusive ions and radicals, according to literature data, increases with increasing magnetic field induction. [ABSTRACT FROM AUTHOR]

It has been widely acknowledged that traditional packers will lose their elastic performance in the context of long periods of operation due to plastic deformation. This paper will introduce a swellable packer that can reduce the failure cases of production effectively. The deformation of the packer rubber in different media and temperatures has been analyzed. The pressure test of several packer rubber under different media is carried out in this paper. The reasonable expansion clearance between the rubber tube and the well wall is obtained by strength calculation to ensure the sealing reliability of the packer. Finally, the thermomechanical coupling calculation of the packer with different structural sizes is carried out. Experiments at different temperatures show that the higher saline concentration is associated with a lower expansion rate and a larger expansion rate in clear water. At the same time, the expansion of volume in clear water increases. In addition, the higher the external temperature is, the larger the temperature gradient is. When the temperature of the outer ring is between 100°C and 140°C, the internal temperature rises to 37°C under the thermomechanical coupling effect. [ABSTRACT FROM AUTHOR]

Copyright of Fly Ash Comprehensive Utilization is the property of Hebei Fly Ash Comprehensive Utilization Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of each component and its additive amount（mass fraction/%） on the fire resistance of waterborne epoxy resin intumescence fire retardant coating were studied. For intumescent flame retardant（IFR）: the orthogonal experiment of ammonium polyphosphate（APP）, mela mine（MEL）, pentaerythritol（PER） and the single factor variable experiment of expanded graphite（EG） were carried out. TG-DTG, DSC and FT-IR were used to analyze and study the thermal stability of fire retardant coating and the composition of the carbon layer after combustion, and the optimized fire retardant coating formula was obtained. The results show that the waterborne epoxy resin（m（E51）∶m（E20）=3∶2） was used as the film for ming material, when the additive amounts of intumescent flame retardant and expanded graphite were 26%（APP）, 12%（MEL）, 10%（PER） and 4%（EG）, respectively, the ultimate refractory time of the coating reached 31.7 min, the expansion rate was 11.7, and the expanded carbon layer was complete and dense. The temperature corresponding to the maximum decomposition rate of fire retardant coating is 331.4 ℃, the intumescent flame retardant in 200-350 ℃ to complete the decomposition, 800 ℃ residual carbon content is 49.9%, mainly composed of polyaromatic rings, phosphate organic compounds and titanium pyrophosphate inorganic compounds. The addition of titanium dioxide, magnesium hydroxide and mineral fiber can effectively improve the fire resistance and the strength of the expanded carbon layer. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Southeast University / Dongnan Daxue Xuebao is the property of Journal of Southeast University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As a new lightweight and energy absorbing structure, aluminum foam special-shaped parts have broad application prospects in many industrial fields, especially in the automotive industry. Aluminum foam special-shaped parts are prepared by foamable precursors foaming in closed cavities. The foam formation process is very different from free foaming; systematic researches on foaming behavior of AlSi8Mg4 precursors at fixed expansion rates (200–500%) in closed cavity are conducted. Results show that as foaming time increases, pore structure evolution shows an obvious homogenization trend except 500% expansion rate; with the increase in expansion rate, the volume of pore-free zone decreases gradually until it disappears; for 300 and 400% expansion rates, as foaming time increases, pore merging phenomenon gradually occurs, especially at 400% expansion rate. Different from the above rules, obvious free foaming characteristics are shown at 500% expansion rate. [ABSTRACT FROM AUTHOR]

Rosaceae is one of the major families in the plant kingdom with important economic value. However, many of them are attacked by Valsa canker, resulting in serious loss of production and profits. Nucleotide-binding leucine-rich repeats (NLRs) play a key role in the plant immune response as the largest class of resistance genes. Currently, we performed a genome-wide identification of NLR genes in Rosaceae and revealed some NLR genes in response to Valsa canker using multispecies bioinformatics including co-expression network analysis and RNASeq data. A total of 3718 NLR genes were identified from genomes of 19 plant species (include 9 Rosaceae plants) and classified them into 15 clades. The NLRs display species- and group-specific expansions that are derived from both the whole genome duplication and the tandem duplication. Additionally, the expression of some NLR members was low under normal growth conditions in various plant tissues, while significantly enhanced after the infection of Valsa canker. Furthermore, co-expression network analysis shows that the 13 NLR members were distributed in key nodes of differentially expressed genes which could be considered as promosing key regulators for the resistance of Valsa canker. Therefore, our findings provide a reference for the evolution of NLR genes in Rosaceae and the key regulators of Valsa canker resistance. [ABSTRACT FROM AUTHOR]

Rosaceae is an economically important plant family that can be affected by a multitude of pathogenic microbes, some of which can cause dramatic losses in production. As a type of pattern-recognition receptor, receptor-like proteins (RLPs) are considered vital regulators of plant immunity. Based on genome-wide identification, bioinformatic analysis, and functional determination, we investigated the evolutionary characteristics of RLPs, and specifically those that regulate Valsa canker, a devastating fungal disease affecting apple and pear production. A total of 3028 RLPs from the genomes of 19 species, including nine Rosaceae, were divided into 24 subfamilies. Five subfamilies and seven co-expression modules were found to be involved in the responses to Valsa canker signals of the resistant pear rootstock Pyrus betulifolia 'Duli-G03'. Fourteen RLPs were subsequently screened as candidate genes for regulation of resistance. Among these, PbeRP23 (Chr13.g24394) and PbeRP27 (Chr16.g31400) were identified as key resistance genes that rapidly enhance the resistance of 'Duli-G03' and strongly initiate immune responses, and hence they have potential for further functional exploration and breeding applications for resistance to Valsa canker. In addition, as a consequence of this work we have established optimal methods for the classification and screening of disease-resistant RLPs. [ABSTRACT FROM AUTHOR]

The work focuses on a study of the hydration characteristics and expansion behaviour of Portland cement with B-doped MgO at an early age. The B--doped MgO was prepared from the co-calcination of a magnesium hydroxide reagent and a mixture of magnesium hydroxide and boric acid at 800 °C. The hydration process, products, and the porosity of pastes were investigated. Meanwhile, the physical and mechanical properties of the mortars were also determined. The results show that the co-calcination of B and magnesium at 800 °C changes the characteristics of the MgO crystals and their activity. With an increase in the dosage of B, the dimensions of the MgO crystals become smaller, and the specific surface area increases, but the activity decreases. The mortars with B-doped MgO show a higher expansion rate. The incorporation of B-doped MgO alters the hydration process of the cement pastes; 4% B-doped MgO incorporation leads to the most increased cumulative heat at 120 h. The content of Mg(OH)₂ formed in the sample is the highest compared to that of the others. The initial setting time of cement paste is delayed by incorporating B-doped MgO. The higher the dosage of B, the later the initial setting time. The B-doped MgO incorporation increases the compressive strength of the cement pastes at 3 days, but significantly decreases at 28 days.

Utilizing self-foaming filling material to fill the hollow area is an effective way to settle the issues of low rate and poor effect of filling and roofing in the large stope. There are fewer studies related to the expansion rate, hydration exotherm and strength properties of self-foaming fillers in mines. Based on this, this paper investigates the expansion characteristics, hydration exothermic characteristics and compressive strength characteristics of the self-foaming filler under different cement-tailings ratios (1:4, 1:6, 1:8), reveals the hydration reaction mechanism of the material and its microscopic characteristics through XRD, TG and SEM tests, and evaluates the application effect and economy of the self-foaming filler in practical engineering with the background of Mashong Iron Ore Mine. The main findings are as follows: (1) The volumetric expansion of self-foaming filling material can be divided into the initial stage Ⅰ (0–1.5 h), the rapid reaction stage Ⅱ (1.5–8 h) and the stabilization stage, and as the cement-tailings ratio grows, the expansion rate of the filling body increases, and the expansion rate of the filling material with 1:4 ratio is as high as 20.4 %. (2) The hydration process of a self-foaming filled body does not contain induction and acceleration stages; under the same conditions, the self-foaming filled body has more exothermic heat of hydration than that of a self-foaming filled body by about 50 J/g, and the bigger the cement-tailings ratio, the bigger the hydration exothermic rate and exothermic quantity. (3) The compressive strength of self-foaming filler is inferior to the strength of conventional filler, the higher the cement-tailings ratio, the greater the degree of hydration, the more hydration products are produced, and the greater the compressive strength. (4) The bigger the ratio of gray sand, the greater the proportion of macropores and the actual engineering of self-foaming filling materials to catch the top rate of up to 98 %, directly saving the total cost of 11.6 %. The above research results can offer theoretical support and scientific guidance for the utilization of spontaneous foam materials to fill the goaf and control the roof rate, temperature, and strength of the stope. • Self-foam materials significantly increase the expansion rate of the filled body. • The hydration process of the self-foam material did not include the induction and acceleration stages. • The larger the cement-tailings ratio, the more hydration products and compressive strength of the self-foam filling material. • The self-foam filling material effectively improves the roof rate of the stope and reduces the filling cost.. [ABSTRACT FROM AUTHOR]

Humans are facilitating the introduction and range expansion of invasive alien species (IAS), which have negatively impacted ecological and socio-economic systems worldwide. Understanding the global diffusion of IAS is important for developing environmental policies and management strategies. We estimate the rate of increase and the doubling times of the number of new records of 178 IAS using a global dataset with c. 3.4 million records obtained over c. 100 years. Here, we show that the number of records of IAS have exponentially increased with a mean double time of c. 14 years across the Earth. For the most analysed species, the number of records increased faster in the non-native than native continents, suggesting that such IAS might be exponentially expanding their range size. We also found that each continent has a taxonomic group with a particular increase in IAS records. Governments and scientists should pay attention to these taxonomic groups to implement appropriate control or management actions. Our study provides an indication that the current local, regional and continental efforts to control invasions may be not sufficient at the global scale. This is a concerning situation given the great number of areas available for invasion worldwide. [ABSTRACT FROM AUTHOR]

Copyright of Pearl River is the property of Pearl River Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Excessive extraction of gravel and sand material from streams leads to major changes in ecosystems, failure of hydraulic structures, lowering of the groundwater table, morphological changes in rivers, etc. Experiments were conducted in this study to investigate spatio-temporal morphological changes in trapezoidal sediment mining pits of different dimensions and composed of cohesionless sediment. Sediment mining pit evolution is described in two phases, namely an expansion and a migration phase. At the initiation of the flow, the pit expands rapidly, and such expansion is higher for a deeper pit. During the expansion phase, maximum residual depth is found at the upstream edge of the pit. The migration speed of a pit during the migration phase is slow in the early flow stage and increases until the pit is filled with sediment. During the migration phase, the maximum residual depth decreases and shifts to the downstream edge of the pit. During the expansion phase, the downstream nick preserves a similar angle to the angle of repose of the bed material, but the upstream nick preserves a similar angle during the migration phase. The filling rate of a sediment mining pit is mostly determined by the pit depth and the bedload transport index. Regression relationships were proposed for estimating expansion rate, migration speed, upstream and downstream expansion lengths, filling and residual depths, and effective length of the mining pit. The existing equations for the computation of migration speed of the sediment mining pit were checked for their performance using the present study data. The performance results show that the proposed equation predicts migration speed more accurately than the existing equations. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering Geology / Gongcheng Dizhi Xuebao is the property of Journal of Engineering Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: In the present study, an attempt has been made to compare the governance patterns in relation to the coronavirus in the studied countries. Methods: The research method is a comparative study and 31 countries with the highest prevalence of coronavirus have been studied. Secondary data were collected and analyzed from international or regional organizations monitoring coronavirus. Results: The research findings show that in the studied countries 1) the death rate and the expansion rate of coronavirus are at the expected level; 2) despite using similar policies in the fight against Corona, the policy implementation tools are different; 3) management and coordination mechanisms are designed under the supervision of the highest executive authority; 4) governance capacity in the fight against Coronavirus is low, but the government stringency is high; and 5 political stability is the only component of governance excellence that affects the rate of corona expansion. Conclusion: Studies on the fight against Coronavirus have been less conducted with a governance approach. The study was able to reveal the similarities and differences between the governing patterns of the fight against Corona in different countries.

Bentonite demonstrates exceptional water absorption and expansion characteristics, along with a high degree of impermeability. The expansion characteristics of bentonite buffer materials are influenced by the underground aqueous solutions containing various base ions. In this paper, the swelling characteristics of bentonite with different dry densities under the action of different base ions and different concentrations of aqueous solution were studied by indoor limited expansion rate and swelling force tests. And the swelling characteristics of bentonite under the action of salt solution were predicted by Back Propagation Neural Network (BPNN). The findings demonstrated that: The swelling process of bentonite can be categorized into four distinct stages: initial swelling, rapid expansion, gradual enlargement, and stable volumetric increase. The expansion rate of bentonite is influenced by the dry density, as well as the type and concentration of the solution. The influence of various solutions on the expansion rate of bentonite follows the order: NaCl < CaCl 2 ≈ MgCl 2 < KCl. The type and concentration of the solution, as well as the initial dry density of the sample, exert significant influence on the swelling force of bentonite. The swelling characteristics of bentonite are accurately predicted by BPNN. The findings of this study offer valuable insights for the scientific utilization and rational disposal of bentonite in engineering applications. • The expansion rate is related to dry density and solution concentration. • The inhibition effect of different salt solutions on swelling deformation is different. • The solution concentration affects hydration degradation of bentonite crystals. • BPNN can be used to predict the swelling properties of bentonite. [ABSTRACT FROM AUTHOR]

This study investigates the effects of physical grinding (ball, impact, and jet milling) and chemical modification (using various dosages of Na 2 SO 4 , CaO, triethanolamine (TEA), and their composite modifiers) on CFBCS. The fluidity, flexural strength, compressive strength, and expansion rate of different modification methods were tested. Microstructural and phase composition analyses were conducted using X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, mercury intrusion porosimetry, and thermogravimetry-differential thermogravimetry. The results indicated that impact milling improved mortar fluidity by 2.9 % compared to ball milling, while jet milling reduced it by 5.7 %. Chemical modifications decreased paste fluidity but increased mortar strength and reduced expansion rates. Impact milling and jet milling improved 28-day compressive strength by 13.76 % and 16.01 %, respectively, and reduced the 90-day expansion rate by 0.007 % and 0.012 %, respectively. Composite chemical modification (CM-C) enhanced 28-day compressive strength by 23.88 % and reduced the 90-day expansion rate by 0.019 %. Microscopic analysis shows that modification reduced the pores and pore size of the mortar while increasing the hydration products. After TEA modification, rod-shaped AFt forms a reticulated structure, with C–S–H gel and CH crystals adhering to it. The hydration products of CFBCS mortar formed a network after jet milling, and the addition of composite modifiers resulted in a layered, dense structure. • Impact milling improved fluidity. • Combined modifiers reduced expansion. • Jet milling and modifiers improved hydration. [ABSTRACT FROM AUTHOR]

The post-peak behavior and fracture characteristics of hard rock are correlated with the stability and bearing capacity of engineering rock mass. However, there are relatively few research studies on the post-peak mechanical behavior and fracture characteristics of hard rock under true triaxial stress. Therefore, this study carried out relevant true triaxial compression tests and acoustic emission (AE) monitoring. It is concluded that under a true triaxial condition, the number of post-peak steps increases first and then decreases with the increasing σ2, which implies that the rock failure evolves from shear failure to a more complex tension–shear mixed failure and finally evolves into a failure mode dominated by tensile failure. The overall level of the rock fracture angle (θ) at low σ3 is higher than that at high σ3. In the range of stress level in this study, when σ3 is high, the fracture angle of granite increases with increasing σ2, and its regularity is obvious, while when σ3 is low, the regularity of the fracture angle increases with the increasing σ2 is not obvious. It is found that there are three different types of cracking processes in granite. Meanwhile, the expansion rates of three different racking types are calculated by simplified treatment, which are about the order of 10−5–10–4 m/s. The research results of this study could supply a useful reference for the understanding of deep hard rock fracture behavior.

Due to the rapid hydration of CaO-based expansive agent (CEA) in the early age, besides deformation, the early mechanical performance of marine concrete blended with CEA may also be affected. However, the mechanism of early strength evolution is unclear. In this paper, the influence of different CEA dosage on the early compressive strength and deformation of cement paste containing 60% slag during the first 72 h was investigated. The results indicate that, in addition to good compensation for shrinkage, the early compressive strength of cement paste mixed with 2% CEA was always greater than that of the reference sample, increasing by 9.2% at 72 h. When the CEA dosage increased to 4%, 6%, and 8%, the growth rate of compressive strength presented a trend of first increasing, then gradually decreasing, and finally increasing again. Their compressive strengths at 72 h were reduced by 40.0%, 53.3%, and 66.5%, respectively. The improvement of compressive strength was attributed to the fact that more calcium hydroxide produced by CEA hydration accelerated the hydration of slag, which could generate more C–S–H gel and densify the microstructure. The slowdown in compressive strength development was due to the internal damage caused by the high expansion stress generated by the rapid hydration of the high dosage CEA. Hopefully, the outcomes of this research can provide new insights into understanding the early mechanical properties evolution of marine concrete containing CEA. [ABSTRACT FROM AUTHOR]

The expansion of oak processionary moth (OPM) in South‐East England continues despite ongoing efforts to control the pest since its introduction in 2006.Using locations of OPM larval nests, supplied by the Forestry Commission and recorded as part of ongoing surveillance and control measures from 2006 onwards, we show that the expansion of the range of OPM in South‐East England up to 2019 was biphasic with a higher rate of expansion from 2015 onwards.The maximum rate of OPM range expansion in the United Kingdom from 2006 to 2014 was estimated as 1.66 km/year (95% CI = [1.22, 2.09]), whereas the 2015–2019 expansion rate was estimated as 6.17 km/year (95% CI = [5.49, 6.84]). This corresponds to an estimated species range distribution area of 7077 km2 in 2019.To explain the faster expansion of OPM range from 2015 onwards, we discuss potential reasons that include: natural capability of species of both short‐ and long‐distance dispersal; external factors such as environmental heterogeneity; a reduction of active control. [ABSTRACT FROM AUTHOR]

The paper mainly studies the effect of heat treatment with lactic acid on properties of rice flour and quality of dried rice vermicelli and wet rice vermicelli.Indica rice flour by water milling was selected as raw material and treated with different concentration of lactic acid，damp heat or the combination of lactic acid and damp heat.The gelatinization characteristics，solubility，expansion rate，cooking quality and texture of dry and wet rice noodles under different conditions were studied.The experimental results showed that the heat treatment with lactic acid had a significant effect on the gelatinization properties of rice flour.After heat moisture treatment，lactic acid treatment，and heat treatment with lactic acid，the peak viscosity，trough viscosity，attenuation value，final viscosity，and retrogradation value of rice flour were all reduced.The peak viscosity was highest in the lactic acid treatment (pH=4).Heat treatment with lactic acid had a certain influence on the solubility and swelling capacity of rice flour.Compared with the original sample，both the solubility and swelling degree of treated samples were gradually decreased.In the determination of rice vermicelli cooking quality，after the lactic acid treatment (pH = 4)，the broken rate，cooking loss rate of the dried rice vermicelli and wet rice vermicelli all reached the lowest.In the determination of texture quality of rice vermicelli，after heat moisture treatment，lactic acid treatment and heat treatment with lactic acid，the wet rice vermicelli have decreased hardness and chewiness.When the lactic acid treatment (pH=4)，the elasticity of the wet rice vermicelli reaches the maximum.In heat moisture treatment，lactic acid treatment and heat treatment with lactic acid，the viscosity of dried rice vermicelli has decreased，in the lactic acid (pH = 4)，the maximum elasticity of dried rice vermicelli.The final result: In the case of lactic acid treatment (pH = 4)，the effect on improving the properties of rice flour and the quality of rice vermicelli was optimal.

Rosaceae is one of the major families in the plant kingdom with important economic value. However, many of them are attacked by Valsa canker, resulting in serious loss of production and profits. Nucleotide-binding leucine-rich repeats (NLRs) play a key role in the plant immune response as the largest class of resistance genes. Currently, we performed a genome-wide identification of NLR genes in Rosaceae and revealed some NLR genes in response to Valsa canker using multispecies bioinformatics including co-expression network analysis and RNASeq data. A total of 3718 NLR genes were identified from genomes of 19 plant species (include 9 Rosaceae plants) and classified them into 15 clades. The NLRs display species- and group-specific expansions that are derived from both the whole genome duplication and the tandem duplication. Additionally, the expression of some NLR members was low under normal growth conditions in various plant tissues, while significantly enhanced after the infection of Valsa canker. Furthermore, co-expression network analysis shows that the 13 NLR members were distributed in key nodes of differentially expressed genes which could be considered as promosing key regulators for the resistance of Valsa canker. Therefore, our findings provide a reference for the evolution of NLR genes in Rosaceae and the key regulators of Valsa canker resistance.

ElGamal Cryptosystem (EC) is a non-deterministic scheme which produces different outputs for the same input, making the cryptosystem more secure. On the other hand, the efficiency of its cryptosystem is low as it produces a 2:1 expansion in size from plaintext to ciphertext, resulting in a delay in execution time. Therefore, this paper presents a Modified ElGamal Cryptosystem (MEC) to increase the efficiency by speeding up the execution time and reducing the expansion rate in the file size after the encryption process. A comparison between the proposed MEC and the traditional EC is carried out using the same programming environment, and the implementation is tested using text data of different sizes. The results show that the performance of the proposed MEC is better than the traditional EC in terms of execution time and expansion rate. Whereas, the security of the proposed MEC is analogous to the traditional EC, which is based on the difficulty of solving the discrete logarithm problem. [ABSTRACT FROM AUTHOR]

The liquid phase composite — rolling technology is used to prepare foamable preforms with different content of wCu and closed-pore aluminum foams. The effect of wCu, on the pore structure of the aluminum foams was studied. The results show that with the increase of wCu, the uniformity lot' the pore structure increases, and the pore size and the number of large pores produced by pore merging decrease, while the collapsing and aging characteristics of the foam are enhanced. After comparing the expansion curves of preforms with different wCu, it is found that when the wCu, increases, the maximum expansion rate of the preform firstly increases and then decreases and the foaming time to reach the maximum expansion rate is greatly shortened. The microstructure analysis shows that CuAl2O4 and CuAl2 can be formed after adding Cu into A1Si9 alloy. CuAl2O4 increases the viscosity of the melt, reduces the effect of gravity drainage and capillary action, and improves the stability of the foam. CuAl2 melts prior to A1Si9 alloy, forming a molten pool on the grain boundary, and the bubbles nucleate and grow in advance, so that the foaming process is completed ahead of schedule. [ABSTRACT FROM AUTHOR]

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BackgroundType 2 diabetes mellitus (T2DM) patients have a lower risk of abdominal aortic aneurysm (AAA) and its comorbidities, which might be associated with the usage of metformin. The objective of the study was to evaluate the role of metformin in the process of AAA development.MethodPubMed, Embase and Cochrane Library were searched up to May 15th, 2021. We implemented several methods including the risk of bias graph, GRADE system and funnel plot to assess the quality and possible bias of this study. Subgroup analysis and sensitivity analysis were applied to address quality differences and validate the robustness of the final results.ResultTen articles were enrolled after screening 151 articles searched from databases. The pooled results showed that, compared with T2DM patients without metformin, metformin prescription was associated with a slower annual growth rate of the aneurysm (mean difference (MD) -0.67 cm [95% confidence interval (CI) -1.20 ~ -0.15 cm]). Besides, metformin exposure was associated with a lower frequency of AAA events (odds ratio (OR) 0.61 [95% CI 0.41-0.92]).ConclusionMetformin alleviated both annual expansion rate and aneurysm rupture frequency in AAA patients with T2DM.Systematic Review RegistrationPROSPERO, identifier https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=217859 (CRD42020217859).

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Type 2 diabetes mellitus (T2DM) patients have a lower risk of abdominal aortic aneurysm (AAA) and its comorbidities, which might be associated with the usage of metformin. The objective of the study was to evaluate the role of metformin in the process of AAA development. Method: PubMed, Embase and Cochrane Library were searched up to May 15th, 2021. We implemented several methods including the risk of bias graph, GRADE system and funnel plot to assess the quality and possible bias of this study. Subgroup analysis and sensitivity analysis were applied to address quality differences and validate the robustness of the final results. Result: Ten articles were enrolled after screening 151 articles searched from databases. The pooled results showed that, compared with T2DM patients without metformin, metformin prescription was associated with a slower annual growth rate of the aneurysm (mean difference (MD) -0.67 cm [95% confidence interval (CI) -1.20 ~ -0.15 cm]). Besides, metformin exposure was associated with a lower frequency of AAA events (odds ratio (OR) 0.61 [95% CI 0.41-0.92]). Conclusion: Metformin alleviated both annual expansion rate and aneurysm rupture frequency in AAA patients with T2DM. Systematic Review Registration: PROSPERO, identifier https://www.crd.york.ac.uk/PROSPERO/display%5frecord.php?RecordID=217859 (CRD42020217859). [ABSTRACT FROM AUTHOR]

This study aimed at assessing the land use and land cover change and its effect on the gully expansion in an agricultural and woodland tropical watershed. We used the case study of Luzinzi watershed in South-Kivu, eastern Democratic Republic of Congo (DRC) where gullies are in development. We used very high-resolution (VHR) images downloaded from Google Earth and unmanned aerial vehicles (UAV) images. ArcGIS 10.7 software helped for spatial analysis and images georeferencing while ENVI 5.3 tools were used for classification. The gullies were then digitized and characterized to determine their width, length, depth, surface and volume. The digital elevation model (DEM) was used to determine the contributing area as well as the slope at the gully headcut. The land use at the headcuts and in the gully was extracted from the different land uses obtained from classified images and validated by field measures. Results showed significant changes in land use and land cover throughout the watershed; changes that affected gully expansion. From 2011 to 2020, number of gullies passed from 38 to 201. These gullies were increasing not only in number but also in characteristics such as gully length and headcut. Their volumes increased from year to year in the same trend as woodland and forest reduction. Forest played important role in gully stabilization: gullies located in forest presented a linear retreat rate (~4.6 m) than those in other land uses (~2.4 m) from 2010 to 2020. The forest cover reduced gully surface at linear rate while the depth rate still increased. A forest cover of ~10% led to a gully expansion of ~700 m3 yr−1 and reduced to 300-400 m3 yr−1 with 30% forest coverage. Thus, forest cover at the gully headcut and in the contributing area helped to stabilize gullies. The permanent maintenance of forest and woodland covers as well as the reduction of anthropogenic activities in gullies are to be promoted at the watershed scale along with other measures to contribute to effective land resource management in the region.

Copyright of Steel Pipe is the property of Steel Pipe Magazine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study seeks to discover the change of cloud's expansion rate with self-designed shock wave dispersion system. Transmission, diffraction and reflection could be observed intuitively when shock waves passed through solid particle layers. Results show that the longitudinal motion of particle group greatly influenced cloud's volume growth, thus, the maximum rate of longitudinal expansion of clouds was almost twice that of lateral expansion. The cloud growth rate and volume acceleration increased with smaller particle size, thicker particle layer and stronger shock wave intensity. Also, the expansion rate initially had a drastic decrease, small particles made clouds volume acceleration unstable and experienced a subsequent swift rise. Shock wave intensity influenced diffraction and reflection formation waves as well as the cloud's shape and expansion rate. This study therefore proposed a controlling model for cloud's expansion rate, which could illustrate differences between acceleration stage of dynamic action and deceleration stage of resistance action. Unlabelled Image • The leading factor of cloud volume growth is longitudinal motion of particle group. • The maximum vertical expansion rate of cloud is almost twice that of the lateral. • Small particles make clouds growth acceleration unstable and rise suddenly. • Shock wave strength affects diffracted and back wave formation, then clouds shape. • A controlling mechanism for cloud cluster expansion rate is proposed. [ABSTRACT FROM AUTHOR]

Purpose: Liver transplantation is a curative treatment option for hepatocellular carcinoma. In this review, we aimed to review liver transplantation criteria for hepatocellular carcinoma and patient survivals. Methods: We reviewed literature in terms of liver transplant criteria for hepatocellular carcinoma. Patient eligibility criteria, post-transplant survivals, tumor recurrence and expansion of Milan criteria rates were analyzed. Results: The Milan criteria, after being published in 1996, have become for deceased donor liver transplantation in hepatocellular carcinoma worldwide. Later, many transplant centers published their own liver transplant criteria. Most of the criteria consisted of morphological tumor characteristics based on tumor size and number. The newest published one is Malatya criteria. The 5-year overall survival according the all of the criteria is greater than 50%. There were just one paper which compare criteria according to survival and Malatya criteria were the best amongst extended criteria with 5-year OS 79.7% in that study. Conclusion: It is clear that morphological criteria consisting only of tumor size and number are insufficient in patient selection for liver transplantation and should thus be combined with biological, inflammatory, radiological, pathological and genetic markers that predict the biological behavior of the tumor. Efforts to find the best criteria are still ongoing and 5-year overall survival should be greater than 60%. [ABSTRACT FROM AUTHOR]

Meshed skin grafting is a common technique in operations to minimize surgery on the donor site area. However, the donor site area is empirically determined by surgeons due to the lack of a reliable formula to calculate the donor area required to cover a skin defect. To determine the minimal size for donor skin, the expansion rates of 1.5:1, 3:1, and 6:1 meshed skin graft and the area actually covered by them were investigated in real‐world operations. About 51 patients who received 57 operations with meshed skin grafts were enrolled in this study. The average clinical coverage rates of area in cases in which 1.5:1, 3:1, or 6:1 meshed skin grafting was performed were 1.02, 1.29, or 2.18, respectively. Those rates were notably low when recipient sites were concave. The average expansion rates of 1.5:1, 3:1, and 6:1 meshed skin grafts were about 1.16, 1.61, and 2.32, respectively. These results indicate that the size of donor skin should be about 85%, 60%, and 45% size of the recipient site to achieve the target 1.5:1, 3:1, and 6:1 meshed skin graft, respectively. In addition, the donor area should be adjusted in consideration of the shape of the recipient sites. [ABSTRACT FROM AUTHOR]

The mechanical behaviors of the self‐stressing steel slag aggregate concrete filled steel tubular (SSSACFST) stub column are investigated for practical structural applications. Twelve specimens under axial and eccentric compression are tested. The influences of different parameters, such as the eccentricity, the diameter–thickness ratio of the steel tube and the expansion rate of the steel slag aggregate concrete (SSAC) are studied. The experimental results show that the shear and the bending deformation dominate the failures of the specimens under axial and eccentric compression, respectively. The column with a high diameter–thickness ratio has a low ultimate bearing capacity and ultimate strain. The incremental range of the load capacity and the ultimate axial and circumferential strains of the specimens will be increased by raising the expansion rate of the SSAC. Based on the experimental results, the applicability of the current concrete filled steel tube design provisions for the SSSACFST stub columns is evaluated, and two analytical models for predicting the bearing capacity of the SSSACSFT stub columns under axial and eccentric compression are proposed. [ABSTRACT FROM AUTHOR]

We characterize geometrically the Lyapunov exponents of a cocycle (of arbitrary rank) with respect to a harmonic current defined on a hyperbolic Riemann surface lamination. Our characterizations are formulated in terms of the expansion rates of the cocycle along geodesic rays. [ABSTRACT FROM AUTHOR]