RSC Advances
·
2019
·Vol. 9
·期 46
·26676-26684
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IF 3.049
Qinghao Wu,Dawei Liang,Xiumei Ma,Shanfu Lu,Yan Xiang
Capacitive deionization (CDI) is a novel low-energy green desalination technology that has attracted much attention in recent years, especially for the desalination of low salinity water. One of the key issues in CDI is the electrode materials, and many efforts have been devoted to developing materials with high specific surface areas, appropriate pore distributions, and good electronic conductivity, in order to obtain a high salt adsorption capacity. In this study, chitosan was selected as a precursor for the preparation of high-performance chitosan-based activated carbon (CTS-AC) for use in CDI electrodes via pyrolysis and KOH activation. The results show that CTS-AC800 (activated at 800 °C) has the largest BET specific surface area (2727 m2 g−1), and exhibits an appropriate pore size distribution (<10 nm), nitrogen doping (2.0%) and good electronic conductivity (2.09 S cm−1). The CDI performance results show that the CTS-AC800 electrode has a saturated salt adsorption capacity of 14.12 mg g−1 in a 500 mg L−1 NaCl solution and retains 95% capacity after 150 adsorption–desorption cycles. Thus, chitosan is a promising, sustainable precursor for CDI electrode materials.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY
·
2018
·
IF 1.684
Shiwei Xie,Dan Wei,Peng Yin,Lu Zheng,Tianyu Guo,Yongjian Liu,Lixia Tian,Jin Niu
An 8-week feeding trial was conducted to evaluate the effect of fish-meal replacement on growth performance, protein synthesis and immune response of juvenile Pacific white shrimp, Litopenaeus vannamei reared at low salinity (7‰). Five isonitrogenous and isolipidic diets were formulated to contain graded levels (25, 20, 15, 10 and 5%) of fish-meal. High quality alternative solutions were performed, crystalline amino acids, phytase, mannan oligosaccharides and some micro-nutrients were supplemented in the low fish-meal diets. Each diet was randomly assigned to triplicate tanks, each tank with 30 shrimp (mean weight 0.3 g), the shrimp were fed 3 times a day. Weight gain and survival were decreased with the decreasing dietary fish meal levels. When dietary fish-meal decreased, the gene expression of TOR, Raptor and eIF4E2 in hepatopancreas were decreased with the decreasing fish meal levels, eIF4E2 in intestine was decreased while 4E-BP was increased with the decreasing fish meal levels. The mRNA level of SOD in hepatopancreas decreased, and the expression of GPx and CAT increased with the decreasing FM levels. The Toll pathway was affected by dietary FM levels, the expression of Toll2, TNFSF, MyD88, Rho and p38 in intestine were increased with the decreasing FM levels. The results indicated that at low salinity condition, fish meal level lower than 15% would inhibit the protein synthesis and harm to the health of shrimp.
研究领域:
水产养殖
·
分子生物学
·
营养学
✓ 已验证
DOI
PubMed
高影响因子
APPLIED ENERGY
·
2022
·
IF 11.446
Rukuan Chai,Yuetian Liu,Liang Xue,Zhenhua Rui,Ruicheng Zhao,Jingru Wang
Water reinjection was widely implemented in the geothermal development for not only disposing tailwater but also maintaining reservoir pressure. Accompanying this was the formation damage, especially in the injection of decreased salinity water which was synthesized by adding surface water and condensed water into produced water for inhibiting the process equipment corrosion, treating the cooling tower condensate, and etc. Fine migration is the prevailing mechanism; however, it is insufficient in some scenarios. Multiple experiments were conducted to investigate the characteristics and mechanisms of formation damage of sandstone geothermal reservoirs during the decreased salinity water injection. First, coreflooding (CF), nuclear magnetic resonance (NMR), and contact angle (CA) experiments were conducted to analyze the characteristics of the formation damage. Subsequently, scanning electron microscopy (SEM), X-ray diffraction (XRD), inductively coupled plasma optical emission spectrometry (ICP-OES), and nanoindentation experiments were implemented to study the corresponding mechanisms. Finally, the damage mode of sandstone geothermal reservoirs in decreased salinity water injection was proposed. The CF, NMR, and CA experimental results indicated that the decreased salinity water injection resulted in severe formation damage, as manifested by the reduction of permeability, shrinkage of the pore-throat, and enhancement of the water-wettability of core samples. That is, formation damage not only indicates that the fluid is more difficult to be injected but also that it is more difficult for the injected fluid to flow. As the salinity decreases, these trends gradually enhance. The SEM results illustrated that fine migration is noticeable in decreased salinity water injection, meanwhile mineral dissolution which causes secondary pores and microfracture is also apparent. Both reactions are enhanced as the salinity decreases. The same conclusion was validated by the XRD and ICP-OES results, as manifested by the decrease in the concentrations of clay, K-feldspar, and plagioclase, and the increase in quartz, as well as the emergence of Si 4+ , Mg 2+ , Ca 2+ , and K + in the effluents produced during the decreased salinity water injection. The nanoindentation results explicated that mineral dissolution weakened the mechanical strength of the minerals, which might effectively facilitate compaction. The elastic modulus and hardness of the quartz, K-feldspar, and plagioclase decreased from 107.5&93.7&72.3GPa and 13.7&10.1&7.4GPa of the original sandstone to 108.1&86.0&69.5GPa and 13.6&10.3&6.4GPa of the deionized water flushed one, respectively. In conclusion, formation damage was synergistically dominated by the external cause of compaction and the internal causes of fine migration and mineral dissolution. These factors compressed the pore-throat, decreased the connectivity of the porous media, enhanced the water-wettability of the sandstone surface, and consequently impeded water flow.
研究领域:
地质学
·
石油工程
·
地热能开发
✓ 已验证
DOI
高影响因子
ACS Omega
·
2024
·
IF 3.7
Ernest Peter Maiki,Renyuan Sun,Shaoran Ren,Ayman Mutahar AlRassas
In this study, we explore the impact of monovalent (NaCl) and divalent (CaCl2) brines, coupled with sodium dodecyl sulfate (SDS) surfactant at varying low concentrations, on the detachment and displacement of oil from sandstone rock surfaces. Employing the sessile drop method and molecular dynamics simulations, we scrutinize the behavior of the brine solutions. Our findings reveal that both low salinity and low-salinity surfactant solutions induce a gradual shift in rock wettability toward a more water-wet state. This wettability transformation is not instantaneous but evolves over time, as observed through meticulous molecular motion analyses. Through contact angle measurements and molecular dynamics simulations, we delve into the molecular motion at subpore and micropore scales on sandstone/quartz surfaces. The adsorption of surface-active agents from the oil to the oil–brine interface results in a reduced interfacial tension, significantly contributing to oil displacement. Notably, low salinity concentrations ranging from 1000 to 10,000 ppm exhibit the lowest contact angles within 30 min across all solutions. However, higher concentrations deviate from this declining trend, especially with divalent ions like Ca2+, which bridge polar molecules onto the rock surface, resulting in an increased oil-wetting state. This research unveils the intricate molecular motions involved in employing low-salinity surfactant solutions for oil detachment from surfaces. Furthermore, it provides valuable insights into the underlying forces driving oil detachment and wettability alteration.
研究领域:
石油工程
·
界面化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
·
IF 5.518
Jie Cao,Yingpeng Chen,Xiujun Wang,Jian Zhang,Ying Li,Zhao Hua,Xinming Wang,Shang Zhao
This paper proposes a novel Janus graphene nanofluid that enhances the low salinity water oil flooding performance. Two kinds of Janus hydroxylated graphene oxide (JHGO-1 and JHGO-2) were prepared by the high internal phase emulsion method. JHGO nanosheets were well dispersed in low salinity water, and their zeta potential was lower than −30 mV. Compared with JHGO-1, JHGO-2 has more excellent interfacial properties , remarkably reducing 73% of the oil-water interfacial tension and improving the interfacial viscoelastic modulus and shear viscosity. Furthermore, JHGO can form bubble film, interfacial film, and climbing film at the oil/water interface due to its amphiphilic nature, which endows it with intelligent oil-finding properties. JHGO nanofluid alters the rock surface into strong water-wet and changes the capillary force into the driving force of oil flooding. JHGO nanofluid can also rapidly peel crude oil from rock surfaces by reducing adhesion work and forming disjoining pressure . These excellent interfacial properties help low-salinity nanofluid to have a 15.4% enhanced oil recovery at the ultra-low concentration (50 mg/L). This smart fluid flooding lays the foundation for efficient oilfield development.
研究领域:
石油工程
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材料科学
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界面化学
✓ 已验证
DOI
高影响因子
AQUACULTURE NUTRITION
·
2019
·Vol. 26
·期 3
·683-692
·
IF 2.098
Zequn Li,Xiaoqiang Xue,Huan Yang,Mingling Liao,Yuzhe Han,Zhiqiang Jiang,Tongjun Ren
This study was performed to determine the optimum dietary carbohydrate (CHO) levels of sea cucumber, based on the parameters of growth, digestive enzymes, digestibility, non-specific immune enzymes and acute low-salinity (20 g/L) stress and high-temperature (30°C) stress tolerance. Diets with eight different CHO (dextrin) levels (32.9, 107.6, 192.5, 257.2, 316.8, 428.0, 482.4 and 572.8 g/kg) were fed to sea cucumber juveniles (0.49 ± 0.01 g) for 60 days. Significant higher amylase activity was observed in sea cucumbers fed diet with CHO ranging between 32.9 and 192.5 g/kg than that of other treatments ( p < .05). The sea cucumbers fed with 192.5 g/kg CHO showed significantly higher acid phosphatase activity than the treatments of 482.4 and 572.8 g/kg CHO ( p < .05), and significantly higher alkaline phosphatase activity than other treatments ( p < .05, except 257.2 g/kg). The treatments of 428.0–572.8 g/kg were found significantly lower values than other treatments in apparent digestibility coefficients for dry matter and crude protein ( p < .05). The sea cucumbers fed with 192.5, 257.2 and 316.8 g/kg CHO showed better tolerance to high-temperature (30°C) and low-salinity (20 g/L) stress than other treatments. In brief, the optimal dietary CHO level for the growth of juvenile sea cucumber is 177.96 g/kg. However, excessive CHO will inhibit amylase enzyme activity and decrease digestibility, resulting in low growth of sea cucumber.
研究领域:
水产养殖学
·
海洋生物学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）