查找使用阿拉丁产品的科研文献

Synergistic effects of Janus graphene oxide and surfactants on the heavy oil/water interfacial tension and their application to enhance heavy oil recovery

Han Jia,Pan Huang,Yugui Han,Qiuxia Wang,Xin Wei,Wenjian Huang,Jiajun Dai,Jinyong Song,Hui Yan,Dexin Liu

The interfacial activities of graphene oxide (GO) and two kinds of Janus graphene oxide (JGO150 and JGO400), i.e., GO with one side being modified by two different amount of dodecylamine, were evaluated in various oil/water systems. Based on the results of IFT measurement, JGO showed the greater interfacial activity than original GO, especially for JGO400 which greatly reduced the heavy oil/water IFT to 0.12 mN/m. Molecular dynamic simulations were employed to illustrate the interfacial interaction between GO/JGO and oil molecules. Furthermore, the interaction between three kinds of nano-sheet materials and three types of surfactants, including dodecyltrimethylammonium bromide (DTAB), sodium dodecyl sulfate (SDS), and Triton X-100 (TX-100), were systematically investigated in the heavy oil/water system. The JGO400/DTAB system exhibited excellent synergistic effects to dramatically decrease the heavy oil/water IFT to 8 × 10 −3  mN/m, which was responsible for its remarkable ability to improve heavy oil recovery (19.5%) in core flooding tests.

Study of Janus Amphiphilic Graphene Oxide as a High-Performance Shale Inhibitor and Its Inhibition Mechanism

Lv Kaihe,Huang Pan,Zhou Zhishi,Wei Xin,Luo Qi,Huang Ziming,Yan Hui,Jia Han

Janus amphiphilic graphene oxide (JAGO), modified by dodecylamine on one side of graphene oxide (GO), was investigated for its novel use as a shale inhibitor. JAGO was synthesized by the Pickering emulsion template technology and was characterized by the Fourier-transform infrared spectra, UV-vis spectra, and transmission electron microscopy. Compared to KCl (5%), polyether diamine (2%), and pristine GO (0.2%), JAGO's highest shale recovery rate (75.2% at 80°C) and lowest swelling height of Mt-pellets (2.55 mm, 0.2%) demonstrated its excellent inhibitive property. Furthermore, JAGO acted as a perfect plugging agent and greatly reduced filtration loss. Based on the results of X-ray diffraction, contact angle measurements, and pressure transmission tests, we proposed that the 2D nano-sheet amphiphilic structure of JAGO, which enabled it to be effective both in chemical inhibition and physical plugging, was responsible for its remarkable inhibition performances.

Paraffin/chitosan composite phase change materials fabricated by piercing-solidifying method for thermal energy storage

Qi Honghua,Zhang Ting,Zhang Deyi,Wang Kunjie,Wang Yi

To study the effects of emulsifier content on the structure and thermal properties of encapsulated phase change materials (PCMs), four kinds of paraffin/chitosan (CS) macroencapsulated PCMs with different emulsifier contents were fabricated via the piercing–solidifying method. The effects of emulsifier content on macro-profile, micromorphology, thermal energy storage properties, and thermal durability of the as-prepared composite, as well as the structure of the optimal capsules, were investigated. The results show that the non-spherical degree, average diameter, and compressive strength decreased first and then increased with increase in emulsifier content, resulting in thermal energy storage capacity’s increase at first and then its decrease. The optimal macro-capsules, fabricated at the critical micelle concentration of the emulsifier, present a regular spherical surface and microencapsulated paraffin wax inside. The paraffin content is as high as 85%, with a phase change latent heat of 112.6 J g −1 for melting and 118.7 J g −1 for solidification. The melting enthalpy and weight loss ratio of the optimal paraffin/chitosan composite after 600 heating/cooling cycles only changed to 0.71% and 1.17%, respectively. These results not only suggest that the piercing–solidifying method can be employed to fabricate macro-capsules with high heat storage performance and excellent thermal stability but also reveal that paraffin/CS can be used in thermal management at low temperature.

Dynamic tuning of magnetic phase change composites for solar-thermal conversion and energy storage

Lei Shi,Yanwei Hu,Yijie Bai,Yurong He

Photo-thermal conversion and energy storage using phase change materials are now being applied in industrial processes and technologies, particularly for electronics and thermal systems. This method relies on adding high thermal conductivity fillers, such as nanoparticles, to enhance the phase change process. In the long term, dynamic tuning heat transfer provides a superior means of tuning control the heat transfer efficiency and speed. In this study, a nanofluid phase change material was prepared by adding magnetic nanoparticles, effectively combining the properties of high thermal conductivity and magnetism, in an attempt to develop a magnetically enhanced approach for dynamic tuning of photo-thermal conversion charging. Our results showed that the phase change efficiency of magnetic phase change material can be improved by magnetic field application. With the increasing magnetic strength, the photo-thermal storage efficiency was enhanced, and storage capacity was improved by more than 48%. Meanwhile the steady temperature of the magnetic phase change material increased, enhancing the open-circuit voltage in photo-thermoelectricity experiments. Thus, the proposed method demonstrated in this study achieved superior phase change heat transfer characteristics within a photo-thermal conversion process by dynamically controlling the magnetic field distribution, which should be especially useful for direct solar energy utilisation.

Comparison of an Emulsion- and Solution-Prepared Acrylamide/AMPS Copolymer for a Fluid Loss Agent in Drilling Fluid

Jingyuan Ma,Boru Xia,Peizhi Yu,Yuxiu An

Acrylamide polymers were widely used as oilfield chemical treatment agents because of their wide viscosity range and versatile functions. However, with the increased formation complexity, their shortcomings such as poor solubility and low resistance to temperature, salt, and calcium were gradually exposed. In this paper, acrylamide (AM)/2-acrylamide-2-methyl-1-propane sulfonic acid (AMPS) copolymers were synthesized by aqueous solution polymerization and inverse emulsion polymerization, respectively. The aqueous polymer (W-AM/AMPS) and the inverse emulsion polymer (E-AM/AMPS) were characterized by Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (1H NMR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and particle size analysis. The rheological properties, filtration properties, and sodium ion (Na+) and calcium ion (Ca2+) resistance were investigated. The results showed that E-AM/AMPS not only had a dissolution speed 4 times faster than that of W-AM/AMPS but also had superior shear-thinning performance both before and after aging. The filtration property of the bentonite system containing 2 wt % E-AM/AMPS was also better than that of the bentonite system containing 2 wt % W-AM/AMPS. In addition, E-AM/AMPS also exhibited extremely high tolerance for Na+ and Ca2+. The huge difference between rheological and filtration properties of E-AM/AMPS and W-AM/AMPS in drilling fluid can be attributed to the differences in the polymer microstructure caused by the two polymerization methods. Both FTIR and 1H NMR results showed that more hydrogen bonds were formed between E-AM/AMPS molecular groups and molecular chains, which led to a cross-linked network structure of E-AM/AMPS which was observed by TEM. It was this cross-linked network structure that made E-AM/AMPS have a high viscosity and allowed it to be better adsorbed on bentonite particles, thus exhibiting excellent rheological and filtration behavior. In addition, E-AM/AMPS powder had a high specific surface area so that it can be dissolved in water faster, greatly reducing the time and difficulty of configuring drilling fluid.

A high-throughput system combining microfluidic hydrogel droplets with deep learning for screening the antisolvent-crystallization conditions of active pharmaceutical ingredients

Zhenning Su,Jinxu He,Peipei Zhou,Lu Huang,Jianhua Zhou

Crystallization of active pharmaceutical ingredients (APIs) is a crucial process in the pharmaceutical industry due to its great impact in drug efficacy. However, conventional approaches for screening the optimal crystallization conditions of APIs are usually time-consuming, labor-intensive and expensive. Recently, droplet microfluidic technology has offered an alternative strategy for high-throughput screening of crystallization conditions. Despite its many advantages such as low sample consumption, reduced operation time, increased throughput, etc., some challenges remain to be solved, such as instability of droplets in the long-term and tedious efforts required for extracting useful information from massive data. To solve these problems, a high-throughput system that combined microfluidic hydrogel droplets with deep learning was proposed for the first time to screen the antisolvent-crystallization conditions of APIs. In this system, stable hydrogel droplets containing different concentrations of indomethacin, its solvent and antisolvent were generated on a chip. Crystals of indomethacin with different morphologies were formed in hydrogel droplets, and their optical images were captured by a camera. Then, deep learning was applied to identify the hundreds of indomethacin crystal images and successfully classify the crystal morphologies in a short time; a ternary phase diagram was drawn by combining the experimental results with the recognition results of crystal morphologies, and was used to guide the scale-up preparations of indomethacin crystals as desired. This system, which integrated high throughput preparation, characterization and data analysis, is also useful for screening the crystallization conditions and processes of semiconductors, catalysts, agrochemicals, proteins and other specialty chemicals.

Eco-friendly, cost-effective, and durable guar gum/citric acid complex coating on mesh for oil/water separation

Ziru Ye,Kaibing Huang,Mei Xie,Han Yu,Fan Yang,Mingqi Gao,Ruina Wang,Lei Han,Fenxia Wu

Facile Synthesis of Cobalt-Doped Porous Composites with Amorphous Carbon/Zn Shell for High-Performance Microwave Absorption

Qilei Wu,Huihui Jin,Bin Zhang,Siqi Huo,Shuang Yang,Xiaogang Su,Jun Wang

A facile method for the preparation of microwave absorbers with low density, high microwave absorptivity, and broad band is of paramount importance to the progress in practical application. Herein, commonly-used metal organic frameworks (MOFs) prepared just by mechanical stirring in methanol at room temperature were chosen as sacrificial templates to synthesize porous carbon composites with tunable dielectric and magnetic properties. With the replacement of Co atoms on the surface of zeolitic imidazolate framework-67 (ZIF-67) by Zn atoms, a Co-doped porous carbon composite with a low-dielectric amorphous carbon/Zn shell was constructed after annealing, leading to excellent impedance matching condition. Consequently, the as-obtained composite (Co/C@C-800) shows marvelous microwave absorption properties with an absorption capacity of −43.97 dB and a corresponding effective absorption bandwidth of 4.1 GHz, far exceeding that of the traditional porous carbon and composites directly derived from ZIF-67. The results provide a convenient way to modify MOFs for enhanced microwave absorption materials from the synergy of dielectric and magnetic losses.Keywords:MOFs-derived carbon composites;porous structure;impedance match;microwave absorption

Hierarchically Porous PVA Aerogel for Leakage-Proof Phase Change Materials with Superior Energy Storage Capacity

Li Yang,Jie Yang,Li-Sheng Tang,Chang-Ping Feng,Lu Bai,Rui-Ying Bao,Zheng-Ying Liu,Ming-Bo Yang,Wei Yang

Organic phase change materials (PCMs) have been widely used in the thermal energy storage field, but melt leakage above the phase change temperature has greatly hindered their practical applications. Herein, poly(vinyl alcohol) (PVA) aerogels with hierarchically porous structure are fabricated and introduced into phase change matrices to obtain novel leakage-proof composite PCMs (CPCMs). The thermal storage efficiency of the working substance in the CPCMs reaches as high as 95.6%, maintaining a tremendously high energy storage density. More importantly, the CPCMs exhibit prominent shape stability when heated at 80 °C, higher than the phase change temperature, for 60 h. Finally, the leakage-proof CPCMs exhibit great application potential in the thermal management of electronic devices.

A molecularly imprinted electrochemical BPA sensor based on multi-walled carbon nanotubes modified by CdTe quantum dots for the detection of bisphenol A

Yiyun Zhang,Wenwen Zhang,Liming Zhang,Guangsan Song,Ningwei Wang,Wanzhen Xu,Weihong Huang

An imprinted electrochemical sensor based on multifunctional multi-walled carbon nanotubes was synthesized for detection of bisphenol A (BPA). Molecularly imprinted polymers (MIPs) consist carboxylated quantum dots grafted with aminated multi-walled carbon nanotubes as a carrier, BPA as a template, and 3-aminopropyltriethoxysilane (APTES) as a monomer. The successful recombination of quantum dots allows the electrodes to translate small differences in concentration into large changes in current response. Modified materials were discussed by TEM, SEM, FT-IR, Fluorescence, XRD, together with a series of characterization of electrochemical behavior. The MIPs displayed well selectivity towards BPA and hardly showed response to interferes. Also, the sensor has a high stability (RSD of 5.17%) and repeatability (RSD of 0.43%). Moreover, the current response has a linear relationship range from 0.05 to 50 nmol L −1 , with a detection limit of 0.015 nmol L −1 . Finally, the modified electrode was utilized for the detection of 3 kinds of water samples which indicated that the sensor has potential for future applications in trace detection of BPA in environment water.

Programmable droplet sliding on slippery surface with tunability in both surface microstructure and lubricant

Luo Xin,Lai Hua,Cheng Zhongjun,Liu Pengchang,Li Yufen,Liu Yuyan

Smart slippery surfaces with intelligent liquid droplet manipulation performance have aroused much attention. The lubricant and surface microstructure are two key factors that govern the droplet’s sliding performance. However, for almost all existing surfaces, only one factor can be regulated, which significantly limits their wetting performances and applications. Herein, by integrating the temperature-responsive lubricant and shape memory surface microstructure, we report a novel slippery surface. On this surface, the solid/liquid phase transition of the lubricant provides the surface with the ON/OFF control for droplet’s movement between the sliding state and pinning state, and the tunable surface microstructure based on material’s shape memory effect offers the programmable sliding directions. Due to the combined effect, diverse liquid transportation programs with random ON/OFF manner and arbitrary direction were further demonstrated on this surface. This work advances a new slippery surface with controllable lubricant and surface microstructure, which not only provides insights into the design for smart slippery surfaces but also provides a promising material for application in smart control of droplet motion. Graphical abstract A novel shape memory slippery surface is prepared, on which both the lubricant and surface microstructure can be reversibly controlled.

Well-defined organic–inorganic core–shell structure IPN-P(AA-co-AM) polymer spheres by modified suspension polymerization

Yao Qi,Lan Hai,Li Xin,Chen Youyi

Organic–inorganic interpenetrating network poly (acrylic acid- co -acrylamide) IPN-P(AA-co-AM) polymer sphere with core–shell structure has been synthesized by modified suspension polymerization, which the core is high cross-linked and shell is light cross-linked, respectively. The dispersed phase (water phase) and continuous phase (oil phase), as well as core and shell crosslinking agent are screened based on the water absorption capacity of the polymer spheres. In addition, SiO 2 is applied to endow polymer spheres with excellent thermal and water absorption properties. FTIR, TG, SEM, and XPS analyze the chemical structure, thermal properties, morphology and surface element of polymer spheres, respectively. Particularly, the forming mechanism of polymer spheres and water absorption dynamic model are discussed in detail. The results show that the Organic–inorganic IPN-P(AA-co-AM) polymer spheres are successfully synthesized. The polymer spheres could be wrapped effectively when the SiO 2 content up to 2%. Compared to polymer spheres without SiO 2 , the thermal stability is greatly improved. The optimum core and shell crosslinking agent are pentaerythritol triacrylate (PETA) and sodium alginate, respectively. The maximum absorption capacity of polymer spheres for distilled water and 0.9wt% sodium chloride can up to 922.22 g/g and 93.87 g/g, respectively. Finally, the water absorption of IPN-P(AA-co-AM) polymer spheres dynamic model is closed to second-order.