Ratio Of Material To Water Research Articles

Research on the Anchoring Performance of Green and Low-Carbon Anchoring Materials for Urban Rail Transit Foundation Pit Engineering

Abstract. Currently, most anchoring materials used in engineering are ordinary cement mortar, which has a slow hardening process, a prolonged early strength development, and high carbon emissions. In response to this, this paper proposes a new type of green anchoring material. The anchoring performance of this material is verified through indoor and field tests. Indoor tests on the basic properties of the green anchoring material were conducted, determining the optimal water-material ratio to be between 0.25 and 0.30 through tests on fluidity, setting time, and compressive strength. Field tests studied the ultimate bond strength of the new green anchoring material in typical soil-rock composite strata in Qingdao, confirming its rapid-setting and high-strength anchoring characteristics. The application of this anchoring material can reduce carbon emissions and realize the concept of green and low-carbon environmental protection.

Study on key grouting blocking parameters of gas drainage boreholes in soft coal seams

The construction of gas extraction boreholes in soft coal seams is prone to collapse and deformation, and grouting reinforcement is one of the main methods to solve the problem of efficient sealing. However, the reasonable selection of key grouting parameters still needs further research. In response to the problem of selecting grouting sealing parameters for gas drainage drilling in soft coal seams, based on the “concentric ring” reinforcement sealing technology obtained in previous research, the key parameters and sealing technology of the “concentric ring” reinforcement were studied through theoretical calculation and numerical simulation experiments. The slurry diffusion morphology and range under different grouting pressures and grouting time slurry viscosity were obtained. Finally, in order to explore the application effect of key grouting parameters, on-site industrial tests were conducted in a soft and high gas coal seam. The research results indicate that the optimal grouting pressure for the “retaining wall rock hole ring” should not be less than 3 MPa, the reasonable grouting time should be 10–15 min, and the water material ratio of the grouting material should be greater than 1:1; The use of new reinforcement sealing and grouting technology can ensure long-term good extraction effect. Compared to the testing of drilling sealing effect using ordinary cloth bags with two plugs and one injection, The adoption of new reinforcement sealing technology can effectively prevent the deformation and collapse of the borehole before sealing, and due to two rounds of grouting and pre reinforcement of fractured coal, the sealing effect of the borehole is also relatively good. The research results have important theoretical value for guiding the drilling and sealing grouting engineering of gas extraction in soft coal seams.

Experimental Study on the Effect of the Freeze–Thaw Cycle in an Acidic Environment on the Mechanical Properties of Grout-Reinforced Rock Specimens

A new type of grouting material—FCM (fast cementing material)—is being used in coastal and offshore infrastructure projects, such as harbor and tunnel rehabilitation. In order to investigate how this material performs under different conditions, the compressive strength, failure mode, and surface microscopic changes of different fracture penetration degrees and different crack angles of grout-reinforced specimens formed by the FCM and sandstone were investigated in an acidic environment with pH = 1.1 and after freeze–thaw cycles of 5, 10, 20, and 30 times. In addition, through the preliminary determination of FCM grouting material fluidity and setting time, it was determined that the water-material ratio in this test is 0.3, and the sandstone used has good uniformity. The results show that the strength of the original rock can be matched or even exceeded by the solid grout of FCM and sandstone. Acidic environments and freeze–thaw cycles will erode the specimens, mainly on the surface of the specimens. The fracture penetration degree and crack angle determine the degree of strength reduction of the specimens. The compressive strength of the specimens decreases most rapidly within 10 freeze–thaw cycles. After soaking in acidic solution and a freeze–thaw cycle in an acidic environment, particle shedding occurs on the surface of the grout material and a “honeycomb” area appears on the surface of the sandstone. As the freeze–thaw cycle increases, the particle-shedding area and the honeycomb area increase continuously.

Design and development of light weight porous matrix using industrial waste

The aim of the current study is to optimise the composite mixture of fly ash, rubber waste and Ordinary Portland Cement (OPC)for the design and development of a light weight porous matrix. The composite matrices have been evaluated based on the engineering properties consisting of compressive strength, density, open porosity (VR%) and water-material ratio (WM%). The Scanning Electron Microscopy (SEM) is used for the observation of the microstructure of cement, tyre rubber granules, fly ash and the optimized composite matrix. The compressive strength and density decrease with the increasing quantity of waste tyre rubber granules in the matrix, whereas the porosity of the matrix enhances. Since, the rubber granules act like voids in the composite matrix, results into the development of light weight porous matrix, which is also confirmed by SEM analysis. The study confirms the usability of the composite matrix aslow-cost partition walls or low load bearing structures. The utilization of the waste material reduces the land requirement for huge disposal site as well as reduces the carbon footprint due to the reduced utilization of cement. The composite matrix can be further utilized through proper design mix with additional construction materials such as fine and coarse aggregate to broaden the applications horizon in civil and environmental engineering.

Study on Anchorage Performance of New High-Strength Fast Anchorage Agent

To achieve the efficient, rapid construction of prestressed anchor cables, in this study, through an indoor pull-out test and field basic test, we investigated the mechanical behavior, expansion, drawing performance and bond properties of a new type of high-strength, fast anchorage agent. We analyzed the influence of the water material ratio and curing time on its performance and determined the corresponding construction. It was found that the new anchoring agent could be effectively applied in field construction and achieved a compressive strength of 30 MPa within 30 h. Moreover, during the solidification process, the hydration reaction node could be reached within 5–6 h when the material expansion was and the feedback to the water–material ratio were the strongest. In addition, in the drawing process, the anchorage agent exhibited a strong bond with the reinforcement and the rock layer, and the bonding of the anchorage agent to the rock layer was greater than that of the steel bar. Therefore, in order to provide anchorage, it is necessary to increase the contact area between the steel strand and the anchorage agent.

The advantages of microwave in using engineering spoil to sinter bricks

The difference in process parameters and sintering mechanism between microwave sintering and conventional sintering is studied in this thesis. The muffle furnace is adopted to simulate the conventional sintering. The engineering spoil is used as the raw material to prepare green bodies with different water-material ratios. By testing the weight loss on ignition, sintering shrinkage, water absorption, compressive strength, microstructure and crystalline composition of spoil bricks with different water-material ratios, the effects of the two sintering technologies on the performance of spoil bricks were compared to reach the best solution. The sintering mechanism of spoil bricks in CS and MWS was discussed through linear regression analysis. Through leaching toxicity analysis, the leaching toxicity of raw materials and spoil bricks was tested. The results show that compared with CS, MWS has higher efficiency on ignition, lower energy consumption, and better fixation effect on toxic metal elements. The MWS bricks have greater weight loss on ignition, sintering shrinkage and compressive strength, and lower water absorption. Both technologies will transform the mineral crystals in the raw materials into more stable crystals with basically the same composition through phase change. But the microstructure of the spoil bricks using MWS is denser. Besides, as the moisture content of the green bodies increases, the sintering efficiency of MWS will decrease, while the reverse is true for CS. With the increase of the water-material ratio, the weight loss on ignition and water absorption of MWS and CS bricks will increase, but the sintering shrinkage rate and compressive strength will decrease. In summary, MWS, with a better comprehensive performance, is more efficient and energy-saving than CS, the optimal forming water-material ratio for MWS technology is 0.14.

Preparation of CSHW with Flue Gas Desulfurization Gypsum.

Calcium sulfate hemihydrate whiskers (CSHW), a multi-functional and high value-added building material, were prepared with flue gas desulfurization (FGD) gypsum by hydrothermal method, which could be a reasonable disposal of FGD gypsum. In order to obtain CSHW of a high aspect ratio, a series of manufacturing parameters such as reaction temperature, stirring speed, material–water ratio, and reaction time were investigated. The effect of stabilizing treatment and glycerol concentration on CSHW morphology were also studied by environmental scanning electron microscopy (ESEM) and statistical analysis. The results showed that the optimum preparing conditions of reaction temperature, stirring speed, water–material ratio, and reaction time were 160 °C, 200~300 rpm, 11:1 and 1 h, respectively. Furthermore, stabilizing treatment with octodecyl betaine was necessary for the preparation of CSHW. The final prepared whiskers had smooth surface, uniform morphology, a diameter of 260 nm, and a corresponding aspect ratio of 208.2. Moreover, the addition of glycerol reduced the activity of water, contributing to a lower reaction temperature and much smaller diameter.

Experimental Study on Zhaoyuan Gold Tailings-Based Aerated Concrete

This paper discusses the preparation of aerated concrete using the massive gold tailings stockpiled in Zhaoyuan as the main raw material with a mixture of cement, lime, gypsum, and Al powder. Contents of gold tailings, gypsum, lime, Al powder, and water-material ratio are used as impact factors for orthogonal array test to determine the most optimized formulation. The formula optimized through orthogonal experiments is: gold tailings, 58%; lime, 26%; cement, 11%; gypsum, 5%; Al powder 0.048%; water-material ratio, 0.59. Based on this formula, the specimens have the highest strength and specific strength, being 6.15 MPa and 9.96 MPam3• kg−1, respectively. Dry apparent density is 617.5 kg/m3, which is in compliance with the requirements of the national standard on dry apparent density to be smaller than or equal to 625 kg/m3.

Optimization extraction, structural features and antitumor activity of polysaccharides from Z. jujuba cv. Ruoqiangzao seeds

As a discarded byproduct of jujube (Z. jujuba), its seeds contain various biological components. Response surface methodology was used to optimize ultrasound-assisted heating extraction conditions of polysaccharides from Z. jujuba cv. Ruoqiangzao seeds (ZJSPs). The optimal parameters were as follows: temperature 83.1 °C, time 100 min, ultrasonic power 140 W, and water-material ratio 33.5 mL/g, allowed a maximum yield of 1.97%. One main fraction (ZJSPs-1) was successfully purified by ion-exchange and gel-permeation chromatography. With a molecular weight of 342 kDa, ZJSPs-1 was composed of arabinose, glucose, xylose, galactose and rhamnose. The presence of pyranose-form sugars as well as both α- and β-configurations was validated by FT-IR and 1H NMR. TG/DSC indicated that ZJSPs-1 has a favorable thermal stability. XRD suggested that ZJSPs-1 exhibited both crystalline and amorphous portions. ZJSPs-1 was in aggregates of homogenous-dense honeycomb like structures observed by SEM and AFM. ZJSPs-1 possessed antitumor activities against HeLa cells in a dose- and time-dependent manner at 24 and 48 h with IC50 of 164.6 and 87.1 μg/mL, respectively. Fluorescent microscopic and flow cytometry revealed that ZJSPs-1 inhibited the proliferation of HeLa cells through apoptosis. Z. jujuba seeds are good sources for antitumor polysaccharides in pharmaceutical and food industries.

Ultrasound-assisted Extraction of Polysaccharide from Radix Bupleuri using Response Surface Methodology and Antioxidant Research of the Polysaccharide

This report used Response Surface Methodology (RSM) to analyze the conditions that extracting polysaccharide compound from Radix Bupleuri using ultrasonic wave. For determining the optimal extraction conditions, four independent variables, temperature (°C), ultrasonic intensity (UI, W/cm2), dilution rate (water-material ratio, mL/g) and time (min), were investigated using Box-Behnken design. In the results, the best condition after optimization was dilution rate of 35.0:1, UI of 24.5 W/cm2, temperature of 69.5°C and time of 14.6 min. Extraction efficiency was 7.67% and the purity reached 44.14%. It illustrates that the ultrasound-assisted extraction (UAE) was efficient and suitable for extracting polysaccharide from Radix Bupleuri. This paper also investigated the antioxidant activity of Radix Bupleuri polysaccharide (RBP) on superoxide anion radical, hydroxyl radical, and 2,2-diphenyl-1-picry-hydrazyl (DPPH), in vitro experiment. The result indicated that RBP could remarkably sweep away the hydroxyl radical, and had the capacity for clearing away superoxide radical and DPPH.

Preparation and Sealing Performance of a New Coal Dust Polymer Composite Sealing Material

In this study, a new coal‐dust polymer composite material (CP) was fabricated to improve the borehole gas drainage effect and address the limitations of traditional sealing materials. This material used coal dust generated during underground drilling construction as filler, amino resin as binder, and also some other additives. Based on the orthogonal test scheme, 16 groups of experiments were conducted to investigate the effects of coal‐dust content, water‐material ratio, and cross‐linking agent content on viscosity, 3‐day (3‐d) compressive strength, and gel time of the CP. The influences of the various factors were studied using a range of analytical methods to obtain the optimal proportion of the CP. Moreover, the mechanical property and microstructure of the CP were also analyzed to evaluate the sealing performance of this material. Results showed that this material exhibited obvious plastic characteristic and could provide an effective support for the borehole; it can adapt to the deformation of the borehole to some extent and achieve a long‐term sealing effect. The scanning electron microscopy (SEM) results show a good correlation between the resin molecules and coal dust inside the material, which were conducive to improve the sealing performance of the CP material.

Ultrasonic extraction of pectin from Opuntia ficus indica cladodes after mucilage removal: Optimization of experimental conditions and evaluation of chemical and functional properties.

Ultrasonic assisted extraction (UAE) of pectin from Opuntia ficus indica (OFI) cladodes after mucilage removal was attempted using the response surface methodology. The process variables were optimized by the isovariant central composite design in order to improve the pectin extraction yield. The optimum condition obtained was: sonication time 70min, temperature 70°C, pH 1.5 and the water-material ratio 30ml/g. This condition was validated and the performance of experimental extraction was 18.14%±1.41%, which was closely linked to the predicted value (19.06%). Thus, UAE present a promising alternative to conventional extraction process thanks to its high efficiency which was achieved in less time and at lower temperatures. The pectin extracted by UAE from OFI cladodes (UAEPC) has a low degree of esterification, high uronic acid content, important functional properties and good anti-radical activity. These results are in favor of the use of UAEPC as potential additive in food industry.

Enzymatic-Assisted Microwave Extraction of Total Flavonoids from Bud of Chrysanthemum indicum L. and Evaluation of Biological Activities

Abstract An enzymatic-assisted microwave extraction method was developed to extract total flavonoids from bud of Chrysanthemum indicum L. The factors affecting total flavonoid yield were investigated and optimized by response surface design, and this extraction method was compared with water heating extraction. The antioxidant and antimicrobial activities of total flavonoids were preliminarily evaluated. The results showed that the optimized microwave extraction conditions were as follows: water–material ratio, 25:1 (mL:g); extraction time, 19 min; microwave power, 582 W. Under these conditions, the yield of total flavonoids was 11.21 ± 1.12 %, which was 53.21 % higher than water heating extraction method, and had shorter extraction time. The maximum scavenging capacity of total flavonoids (12 mg/mL) on DPPH, hydroxyl and superoxide anion free radical was 76.6 %, 78.8 % and 58.2 %, respectively. The total flavonoids showed inhibitory effect on Bacillus subtilis, Escherichia coli, Staphylococcus aureus and Saccharomyces cerevisiae, with minimum inhibitory concentration of 8 mg/mL, 4 mg/mL, 4 mg/mL and 8 mg/mL, respectively. This study has provided the technical basis for further optimization of extraction of total flavonoids from bud of C. indicum L.

Extraction Kinetics and Properties of Proanthocyanidins from Pomegranate Peel

Abstract With an objective of developing a safe and efficient method to extract proanthocyanidins products from pomegranate peel for use in nutraceuticals or as food additives, the effects of extraction parameters on the production efficiency, product properties, and extraction kinetics were systematically studied. The results showed that both extraction temperature and water–material ratio had significant effects on the proanthocyanidins content, but the yield was significantly affected only by temperature. The moderate temperature and water–material ratio were beneficial to maintain high proanthocyanidins scavenging activity and good product quality. The second-order extraction and Arrhenius kinetic models were developed and successfully used to predict the proanthocyanidins yield for given conditions tested. Extraction temperature of 60°C, water–material ratio of 30:1 g g−1, and time of 10 min are recommended for proanthocyanidins extraction from pomegranate peel, which corresponded to the highest yield of 40.6 mg g−1 and content of 89.1 mg g−1 having a scavenging activity of 31.5 g g−1, and an attractive reddish yellow color.

Optimization of Ultrasonic Extraction of Polysaccharides from L entinus Edodes Based on Enzymatic Treatment

Ultrasonic extraction based on enzymatic treatment was used to extract polysaccharides from Lentinus edodes. Factors affecting polysaccharides yield were investigated and optimized by response surface methodology. This extraction method was compared with traditional water heating extraction. The antioxidant activity of polysaccharides from L. edodes was evaluated. Results showed that the optimal conditions of ultrasonic extraction were as follows: ultrasound power, 340 W; water–material ratio, 30:1 (mL : g); ultrasound time, 14 min. Under these conditions, the yield of polysaccharides was (14.39 ± 1.13)%, which was obviously higher than water heating extraction. The polysaccharides obtained by this method had good 1,1-dipheny-l-2-picrylhydrazyl (DPPH) radical scavenging activity. This extraction method had notable advantages such as high extraction yield, short extraction time and low extraction temperature. Practical Applications Lentinus edodes is one of the most widely consumed edible mushrooms, and polysaccharides are the most active components. Extraction of polysaccharides from L. edodes is conventionally performed by traditional heating method using water as solvent, which is laborious, time-consuming and requires a large volume of solvent. In the present study, ultrasonic extraction based on enzymatic treatment was applied to the extraction of polysaccharides from L. edodes. Results found that this extraction method had notable advantages such as high extraction yield, short extraction time and low extraction temperature, with great application significance.