Large Specific Surface Area Research Articles

Achieving excellent physico-mechanical properties of Cu matrix composites by incorporating a low content of a three-dimensional graphene network

In-depth investigation of the distribution form of the reinforcement and associated mechanisms has great significance for fabricating highly strengthened and conductive Cu matrix composites. The three-dimensional graphene (3DG) network can withstand more strain due to its large specific surface area, and provides interlinked high-speed conductive paths within the composites. In this study, we propose a feasible method to fabricate 3DG-reinforced Cu matrix composites; here, the Cu foam serves as the initial substrate during the chemical vapour deposition (CVD) process and as the matrix of the composites. Through constructing an ideal 3DG network, the graphene content is approximately 0.28 vol%, and a remarkable 230 % improvement in the ultimate tensile strength (418 MPa) with a high electrical conductivity (97.02 %IACS) is obtained in the composite. The continuous high-quality 3DG network is conducive for achieving excellent physico-mechanical properties of the composites, and the enhanced efficiency is superior. A new concept of fabricating Cu matrix composites was proposed for future research.

Effects of modified coal gasification fine slag on the processing and mechanical properties of natural rubber composites

AbstractCoal gasification fine slag (CGFS) is rich in unburned residual carbon, silica and alumina, and has a large specific surface area, making it a potential polymer‐reinforcing filler. Tea polyphenol (TP)‐modified coal gasification fine slag (TP‐CGFS‐T) was prepared using flotation and modification methods in this study. The effects of unmodified and modified CGFS‐T on the sulfurization performance, processing properties, thermal stability, fracture morphology, and mechanical properties of natural rubber composite materials were investigated. Results indicated that after TP modification, CGFS‐T exhibited highly uniform dispersion on the surface without the agglomeration of fillers. When the dosage of TP‐CGFS‐T was 20 phr, the comprehensive performance of the natural rubber (NR) composite material was optimal, with a tensile strength of 12.12 MPa, the elongation at break of 1208.83%, the tear strength of 30.94 kN/m, and the shore hardness of 38.7 A. As the amount of TP‐CGFS‐T increased, the scorch time of NR increased, which enhanced the processing safety of rubber. This study provides a strategy for treating CGFS, which can both reduce the pollution caused by CGFS and save costs for NR composite materials.Highlight The CGFS is separated into concentrate and tailings by flotation. The compatibility between fillers and the matrix is enhanced by TP modification of CGFS‐T. The composite materials show excellent mechanical and processing properties.

Adsorption performance and mechanism of Arsenic(III) and Arsenic(V) by using copper-manganese binary oxide

ABSTRACT Arsenic contamination threatens the safety of drinking water in many areas of the world. As(V) is less toxic and easier to remove than As(III). Hence, it is essential to oxidise As(III) to As(V). Based on the previous studies, Cu-Mn binary oxide (CMBO) (with a molar ratio of Cu/Mn = 3:1) was prepared by a two-step method. The results showed that CMBO has a large specific surface area (67.74 m2/g) and pore size (16.87 nm). Moreover, CMBO has an inconspicuous crystal structure and abundant hydroxyl groups, which are favourable for arsenic adsorption. The adsorption kinetics results indicated that As(III) was oxidised to As(V) during the adsorption process, and the adsorption rate for As(V) removal was faster than that for As(III) removal. The saturated adsorption capacities of As(III) and As(V) were calculated to be 64.17 mg/g and 84.87 mg/g via the Langmuir isotherm model, respectively. The results of the pH effect studies indicated that acidic conditions promoted the removal of both As(III) and As(V) by CMBO due to the electrostatic attraction. The spectroscopic analysis results demonstrated that Mn oxides within CMBO played a vital role in As(III) oxidation. The removal of As(III) by CMBO was attributed to the synergistic effect of As(III) oxidation by Mn oxides and As sorption by Cu oxides. Overall, CMBO is a promising sorbent with great potential for removing arsenic.

Producing sorbitol from cellulose over Ru-WOX co-doped biochars catalysts

In this work, bifunctional Ru-WOX support on four kinds of biochars using as hydrogenation catalysts to convert cellulose into sorbitol. Four biochar including walnut shell (WS), eucalyptus lignin (EL), pine lignin (PN), and corn cob (CN). The Ru-WOX/biochar catalysts were characterized, and the performance of the catalysts were studied under various conditions. It showed that biochar supports have significantly affected on hydrogenation activity, the sorbitol yields have the order of WS > PN > EL > CN, and found that Ru-WOX/WS achieved 100% cellulose conversion and sorbitol yield as high as 82.6% at 220°C for 4 h, and 3 MPa H2 pressure. The relation of structure-performance showed that biochar from WS facilitated the formation of Ru0 due to its larger specific surface area as well as high ratio of Ru0/Ru4+. The catalytic performance has not changed after using 5 times.

Portable and Flexible Hydrogel Sensor for On-Site Atrazine Assay on Agricultural Products.

There is growing attention focused toward the problems of ecological sustainability and food safety raised from the abuse of herbicides, which underscores the need for the development of a portable and reliable sensor for simple, rapid, and user-friendly on-site analysis of herbicide residues. Herein, a novel multifunctional hydrogel composite is explored to serve as a portable and flexible sensor for the facile and efficient analysis of atrazine (ATZ) residues. The hydrogel electrode is fabricated by doping graphite-phase carbon nitride (g-C3N4) into the aramid nanofiber reinforced poly(vinyl alcohol) hydrogel via a simple solution-casting procedure. Benefiting from the excellent electroactivity and large specific surface area of the solid nanoscale component, the prepared hydrogel sensor is capable of simple, rapid, and sensitive detection of ATZ with a detection limit down to 0.002 ng/mL and per test time less than 1 min. After combination with a smartphone-controlled portable electrochemical analyzer, the flexible sensor exhibited satisfactory analytical performance for the ATZ assay. We further demonstrated the applications of the sensor in the evaluation of the ATZ residues in real water and soil samples as well as the user-friendly on-site point-of-need detection of ATZ residues on various agricultural products. We envision that this flexible and portable sensor will open a new avenue on the development of next-generation analytical tools for herbicide monitoring in the environment and agricultural products.

A mesoporous magnetothermal nanopomegranate with acid-tolerant hierarchical structure for remote controlled drug delivery

Developing acid-tolerant magnetothermal nanoplatform with robust drug loading capacity for remote controlled drug release is challenging in the harsh acid environment of stomach. Herein, a nanopomegranate-type magnetothermal controllable drug release platform (FeCo@G@MSN), consisted of magnetothermal convertor (graphene-isolated FeCo nanocrystal core, FeCo@G) and drug reservoir (mesoporous silica, MSN), with acid-tolerant hierarchical structure was developed. Benefiting from the acid tolerance of graphene and MSN, FeCo@G@MSN was stable in 1 M hydrochloric acid for more than 12 h. The nanopomegranate-type hierarchical structure endowed FeCo@G@MSN with high saturation magnetization (114.9 emu/g) to generate a magnetothermal effect and large specific surface area (293.7 m2/g) to provide ample space for drug loading. As a proof of concept, a heat-triggered nitric oxide (NO) precursor was loaded, and NO were controlled released by breaking of S-NO bonds through localized heat derived from magnetothermal effect of FeCo@G, resulting in an inhibition effect towards Helicobacter pylori. A chemotherapeutic drug (doxorubicin, DOX) was also loaded and controlled released by breaking of hydrogen bonds between silica and DOX under remote an alternating magnetic field, thus exhibiting an inhibition effect towards gastric cancer cells. This work provides an efficient strategy to exploit magnetothermal controlled drug release platform and offers inspiration for the treatment of gastric diseases.

Ti-MOG derived TiO2 facet heterojunction rich in C/Ti3+/Ov for adsorption-photocatalytic removal of pharmaceutical pollutants from water

Developing efficient, stable, and broad-spectrum responsive photocatalysts is an effective way to degrade pharmaceutical pollutants in water. In this work, using concentrated hydrochloric acid (HCl) as a modulator, titanium metal–organic gel (Ti-MOG) was prepared and used as a template for calcination in air to obtain anatase TiO2 facet heterojunction rich in C/Ti3+/oxygen vacancy (Ov) (MOG-TiO2), which has a hierarchical porous structure, large specific surface area, and highly dispersed active site. Compared to P25, P25 + C and MIL-125(Ti) derived TiO2 (MOF-TiO2), MOG-TiO2 exhibited obviously enhanced adsorption-photocatalytic performance for tetracycline (TC) and low concentrations ethenzamide (ETH) under broad-spectrum light irradiation. The photocatalytic degradation efficiency of ETH by MOG-TiO2 reached 92.8, 100 and 98.7 % within 240, 60 and 6 min under Vis, UV and VUV light illumination, respectively, which were much higher than those of P25 (62.7, 33.2 and 73.0 %), P25 + C (61.7, 31.2 and 72.5 %) and MOF-TiO2 (79.2, 86.8 and 88.7 %). Furthermore, concentrated HCl promoted the formation of Ti3+/Ov in MOG-TiO2, which was conducive to the improvement of its photocatalytic performance. MOG-TiO2 also displayed great adsorption-photocatalytic stability and reusability. Moreover, the biotoxicity of TC toward E. coli DH5a obviously decreased after photocatalytic degradation. Based on the TiO2 facet heterojunction rich in C/Ti3+/Ov and the generation of hole, hydroxyl radicals, and superoxide radicals, the possible photocatalytic degradation mechanism of MOG-TiO2 was proposed. Overall, this work provides insights into constructing a novel hierarchical porous carbon-doped facet heterojunction photocatalyst for efficient pharmaceutical contaminants removal.

Shuttle-free zinc–iodine batteries enabled by a cobalt single atom anchored on N-doped porous carbon host with ultra-high specific surface area

Aqueous zinc‑iodine batteries are favorable solutions for grid-level energy storage owing to their cost-effective components and intrinsic safety. Nevertheless, the sluggish conversion kinetics and polyiodide shuttle effect have significantly hindered their practical applications. Herein, a Co single atom anchored on N-doped porous carbon nanosheets (Co-SAs@NPC) was produced through an efficient molten-salt engaged pyrolysis process and further utilized as the iodine host for aqueous zinc-iodine batteries. The large specific surface area (1741 m2 g−1) combined with abundant heteroatom-containing functional groups can afford a tight physical and chemical confinement towards iodine species. Meanwhile, the presence of Co single atoms exhibits high electrocatalytic activity towards I2 reduction reactions. According to the experimental results and DFT theoretical calculations, the resulting Co-SAs@NPC can simultaneously offer generous electrochemical active sites and electrocatalytic activity, which displays a high adsorption ability towards iodide species and boost the reversible redox reactions between iodine and iodides. Consequently, the as-assembled zinc-iodine batteries with Co-SAs@NPC/I2 cathodes can deliver a high specific capacity (295 mA h g−1 at 0.3 A g−1), good rate performance (199 mAh g−1 at 20 A g−1), and long cyclic stability over 10,000 cycles. Additionally, the absence of polyiodide shuttle was analyzed by a series of ex-situ spectrum analyses.

Novel magnetic N-doped biochar derived from sugarcane bagasse and red mud for effective adsorption of tetracycline hydrochloride

In this work, with sugarcane bagasse (SB) and red mud (RM) as raw materials, magnetic nitrogen (N)-doped biochar (MNSB) was synthesized by a facile one-pot pyrolysis method and then applied as an efficient adsorbent to remove tetracycline hydrochloride (TC-HCl) from wastewater. The results of SEM, EDS, VSM, BET, FT-IR, and XPS demonstrated that the synthesized MNSB adsorbent had a large specific surface area, excellent superparamagnetic properties, and rich mesopore pore structures. The batch adsorption experiments revealed that the TC-HCl could be removed 96.3% with the optimal adsorption conditions: MNSB dosage of 0.25g/L, initial pH of 6.58, TC-HCl initial concentration of 20mg/L, and adsorption temperature of 30oC. The analysis of adsorption kinetics and isotherms showed that the adsorption process was mainly controlled by chemisorption, and the theoretical maximum adsorption capacity of TC-HCl on MNSB was 143.9mg/g. Mechanistic analysis revealed that the excellent adsorption process of MNSB for TC-HCl was mainly contributed by pore filling, π–π interaction, hydrogen bonding, and electrostatic attraction. The recycling and settlement experiments demonstrated that MNSB had good stability and settleability. This study successfully opened new prospects that utilizing RM and SB to prepare a low-cost adsorbent to remove TC-HCl from water.

Preparation of amino cellulose aerogel and its formaldehyde adsorption properties

The aerogel prepared from cellulose has the advantages of low density, high porosity, large specific surface area, good gas diffusion and adsorption space, which is a good gas adsorption material. In this study, microcrystalline cellulose was used as raw material, and LiBr ionic liquid was used as a solvent system. In addition, cellulose aerogel was modified by polyethyleneimine, which retained three-dimensional network structure and had excellent formaldehyde adsorption capacity. The adsorption capacity of polyethyleneimine-modified cellulose aerogel (PCA) to formaldehyde can reach 12.3 mg/g at 25 ℃. It was found that the adsorption capacity of PCA aerogel for formaldehyde changed with the increase in nitrogen content. The adsorption of formaldehyde was mainly through the chemical adsorption of the Schiff base reaction between NH2 and formaldehyde molecules in polyethylenimine (PEI).

Hexagonal boron nitride-doped carbon membrane as anode for the enhanced adsorption and electrochemical oxidation of phenol

An activated carbon membrane (ACM) doped with hexagonal boron nitride (h-BN) was fabricated by using activated carbon as the raw material and phenolic resin as the binder. The preparation process involves blending raw materials, ball milling, membrane pressing, and high-temperature carbonization. The conductive ACM was employed as an anode to constitute an electrochemical membrane reactor (EMR) for phenol removal. The effect of h-BN doping rate (0–5wt.%) on the properties of ACM was explored. Results showed that ACM1 (1wt.% h-BN) displayed a small pore size (20nm), high porosity (41.6%), large specific surface area (446.8 m2/g), and strong mechanical strength (15.4MPa) compared to the pristine ACM0. The oxygen precipitation potential of ACM1 (2.11V) was much higher than that of ACM0 (1.53V), thus reducing oxygen generation at the anode in EMR for phenol degradation. The phenol removal rate of phenol obtained from EMR with ACM1 as the anode at 1.5V was up to 95.6%, which was much higher than that for ACM0 (39.3%). Density functional theory (DFT) calculations and experimental results confirmed that h-BN-doping enhanced the adsorption active sites, and adsorption energy, leading to the high performance of EMR for phenol removal. In addition, the equilibrium adsorption capacity of ACM1 (10.2mg/g) was much higher than that of ACM0 (3.7mg/g). The C atoms adjacent to pyridine N in ACM1 were identified as the adsorption and active catalytic sites by X-ray photoelectron spectroscopy (XPS) and DFT calculations. Therefore, this study sheds light on the design and fabrication of conductive carbon membranes for enhanced performance in industrial wastewater treatment.

Fabrication of an electrochemical sensing platform based on MWCNT-CONH-66-UiO and PEDOT:PSS for highly sensitive and rapid detection of sunset yellow

The out-of-range, overdose and illegal usage of sunset yellow azo dye in food will cause great damage to food safety and consumer health. In this work, a novel electrochemical sensing platform toward sunset yellow detection was prepared based on the amidated MWCNT-CONH-66-UiO and poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). In MWCNT-CONH-66-UiO, the –NHCO- is produced by the amidation reaction between zirconium 2-amino terephthalate (UiO-66-NH2) and carbonylated multi-walled carbon nanotubes (MWCNT-COOH), which play significant role for the enhancement of the sensing properties of MWCNT-CONH-66-UiO/PEDOT:PSS composite. PEDOT:PSS acts as a conducting film coated on MWCNT-CONH-66-UiO and alleviates the electrooxidation of –NHCO-. The large specific surface area, good conductivity, and outstanding synergistic effect of the composite trigger off prominent sensing properties of MWCNT-CONH-66-UiO/PEDOT:PSS toward sunset yellow detection with the lowest detection limit as 3.3 nM and a sensitivity as 6.6 mA mM−1 cm−2 (active area of 0.15 cm2). Additionally, this sensor shows satisfactory results for sunset yellow detection in plain cake and marinating meat via DPV in comparison to the high-performance liquid chromatography method. The research results in this work will provide technical support for the rapid and efficient detection of azo dyes in food, animal feeds, and industrial wastewater.

Morphology modulation of ZnO microspheres and improvement of triethylamine detection performance by introducing carbon dots

Microspherical ZnO composites were prepared by introducing carbon dots (CDs) in situ by a one-step hydrothermal method. The effects of precursor and calcination treatments on the microstructure and morphology, compositional features and triethylamine (TEA) detection were carefully investigated. The results show that the addition of excess urea promotes the formation of CDs, the produced UC-ZnO composite presents microspheres with relatively smooth surface after calcination, and the retained CDs form heterojunctions with ZnO. TC-ZnO composite produced by adding excess trisodium citrate displays bowl-shaped depressions on the surface. After calcination, the porous structures with large specific surface area and carbon incorporation are achieved. The two composites show improved gas-sensitive response and reduced detection limit for TEA. The sensitivity for 100 ppm TEA at the optimal operating temperature of 350°C is 357 for UC-ZnO and 526 for TC-ZnO sensor, which are 21% and 80% higher than that of pure ZnO, respectively. The TC-ZnO sensor possesses an excellent low detection limit of 32 ppb. The introduction of CDs effectively modulates the morphology and interface state of ZnO microspheres, and improves the gas-sensitive performance.

Tightly and abundantly contacted Z-scheme heterojunction of Bi-modified TiO2/BiOCl: In-situ construction and boosting visible-light-driven purification of liquor brewing wastewater

The lower specific surface area and limited surface contact between BiOCl and TiO2 in composite fabricated by hybridization of TiO2 with BiOCl extremely hinder its catalytic performance. In this work, the area of interface contact between BiOCl and TiO2 was increased through the mediation of SiO2, and a Bi-modified ternary 0D/2D/2D TiO2/BiOCl Z-scheme heterojunction photocatalyst with large specific surface area (= 237.83 m2g−1) and surface plasmon resonance (SPR) effect was constructed in situ by ingeniously utilizing the reduction of carbon species generated during the calcination process. The results show that the COD removal rate of Bi/TBOC-10% for real liquor brewing wastewater (LBW) reaches 90.5% after 10 hours of visible light irradiation, which is 2.6 times and 2.1 times that of TiO2 and Degussa P25, respectively. The COD removal rate of the composite was reduced only by 8.9% after five cycles of performance test (50 h). Photoluminescence spectroscopy (PL), Transient Photocurrent Response (TPR), Electrochemical Impedance Spectroscopy (EIS) and BET characterization suggest that its excellent photocatalytic activity should be attributed to the Z-scheme heterojunction that broadens the light absorption range while retains strong oxidation-reduction active sites, the SPR effect that facilitates the separation and migration of photogenerated carriers, and high specific surface area of the composite that provides more active sites for the photodegradation reaction.

Ice/salt assisted synthesis of ultrathin two-dimensional nitrogen doped carbon nanosheets for fast lithium storage

Two-dimensional carbon nanosheets have garnered considerable interest as promising anode materials in energy storage devices due to their large specific surface area and excellent conductivity. The efficient synthesis of ultrathin nitrogen-doped carbon nanosheets is achieved with the aid of cysteine, employing a green ice/salt-assisted strategy. Ice influences the growth direction of salt crystals and determines the distribution of sodium lignosulfonate on the surfaces of both ice and salt crystals. The introduction of methionine incorporates heteroatoms, altering the electronic structure and chemical activity of the material, thereby effectively enhancing its lithium storage performance. The initial charge capacity of the optimized sample reached 766.4 mA h g−1 at a current density of 0.2 A g−1, maintaining a capacity of 571.1 mA h g−1 after 100 cycles. This study presents an innovative method for fabricating ultrathin carbon nanosheets using eco-friendly, cost-effective sodium lignosulfonate, showcasing a promising candidate for lithium-ion batteries and future energy storage technologies.

Eco-friendly synthesis of cluster-like Dy2Ce2O7 nanoparticles using orange juice and their application in electrochemical determination of isoniazid

In this study, cluster-like (CL) Dy2Ce2O7 nanoparticles were synthesized via an easy and rapid sonochemical pathway. X-ray diffraction (XRD), and field emission scanning electron microscopy (FE-SEM) were used for the characterization of nanoparticles. The construction of an electrochemical sensor was performed to determine isoniazid (IZN) based on ionic liquid (IL) and the cluster-like nanostructure of Dy2Ce2O7 modified carbon paste electrode (CL-Dy2Ce2O7/IL/CPE). Using the fabricated sensor, cyclic voltammetry (CV) along with differential pulse voltammetry (DPV) have been utilized to examine the catalytic activity of the modified electrode toward oxidation of IZN in 0.1 M phosphate buffer solution (PBS) with pH of 7.0. The large specific surface area and electrocatalytic properties of CL-Dy2Ce2O7 as well as the good electrical conductivity of ionic liquid greatly enhanced the current signal of the IZN at the CL-Dy2Ce2O7/IL/CPE. The process at the surface of the electrode was under the diffusion control mechanism and the diffusion coefficient for IZN was 1.08 × 10−5 cm2/s. Additionally, with a low detection limit of 9.0 nM, the peak current of IZN rose linearly with concentration in the range of 0.02–340.0 μM. Our findings demonstrate that the sensitive and selective detection of IZN in pharmaceutical and biological samples can be achieved using the CL-Dy2Ce2O7/IL/CPE.

Superhydrophilic/superaerophobic CoP/CoMoO4 multi-level hierarchitecture electrocatalyst for urea-assisted hydrogen evolution reaction in alkaline media

Utilizing the thermodynamically favorable urea oxidation reaction instead of the anodic oxygen precipitation reaction is an alternative pathway for the energy-saving hydrogen production. Therefore, it is significant to explore advanced electrocatalysts for both HER and UOR. In this work, a dendritic heteroarchitectures of 2D CoMoO4 nanosheets deposited on 1D CoP nanoneedles (CoP/CoMoO4-CC) was fabricated as bifunctional electrocatalyst. 1D CoP nanostructure with fast charge transport pathways and 2D CoMoO4 nanostructure with large specific surface area and short paths for electron/mass transport. The unique morphology endows the superhydrophilic and superaerophobic properties, allowing for the rapid contact with the reactants and rapid removal of surface-generated gases. As a result, the CoP/CoMoO4-CC shows efficient bifunctional activity. This work offers a new avenue to rationally design bifunctional electrocatalysts for large-scale practical hydrogen production.

Insights into sunlight-driven transformation of tetracycline by iron (hydr)oxides: The dominating role of self-generated hydrogen peroxide

Iron (hydr)oxides are abundant in surface environment, and actively participate in the transformation of organic pollutants due to their large specific surface areas and redox activity. This work investigated the transformation of tetracycline (TC) in the presence of three common iron (hydr)oxides, hematite (Hem), goethite (Goe), and ferrihydrite (Fh), under simulated sunlight irradiation. These iron (hydr)oxides exhibited photoactivity and facilitated the transformation of TC with the initial phototransformation rates decreased in the order of: Hem > Fh > Goe. The linear correlation between TC removal efficiency and the yield of HO• suggests that HO• dominated TC transformation. The HO• was produced by UV-induced decomposition of self-generated H2O2 and surface Fe2+-triggered photo-Fenton reaction. The experimental results indicate that the generation of HO• was controlled by H2O2, while surface Fe2+ was in excess. Sunlight-driven H2O2 production in the presence of the highly crystalline Hem and Goe occurred through a one-step two-electron reduction pathway, while the process was contributed by both O2-induced Fe2+ oxidation and direct reduction of O2 by electrons on the conduction band in the presence of the poorly crystalline Fh. These findings demonstrate that sunlight may significantly accelerate the degradation of organic pollutants in the presence of iron (hydr)oxides.

Nanocrystalline cellulose as a reinforcing agent for poly (vinyl alcohol)/ gellan-gum-based composite film for moxifloxacin ocular delivery

Nanocrystalline cellulose (NCC) is a star material in drug delivery applications due to its good biocompatibility, large specific surface area, high tensile strength (TS), and high hydrophilicity. Poly(Vinyl Alcohol)/Gellan-gum-based innovative composite film has been prepared using nanocrystalline cellulose (PVA/GG/NCC) as a strengthening agent for ocular delivery of moxifloxacin (MOX) via solvent casting method. Impedance analysis was studied using the capacitive sensing technique for examining new capacitance nature of the nanocomposite MOX film. Antimicrobial properties of films were evaluated using Pseudomonas aeruginosa and Staphylococcus aureus as gram-negative and gram-positive bacteria respectively by disc diffusion technique. XRD revealed the characteristic peak of NCC and the amorphous form of the drug. Sustained in vitro release and enhanced corneal permeation of drug were noticed in the presence of NCC. Polymer matrix enhanced the mechanical properties (tensile strength 22.05 to 28.41 MPa) and impedance behavior (resistance 59.23 to 213.23 Ω) in the film due to the presence of NCC rather than its absence (16.78 MPa and 39.03 Ω respectively). Occurrence of NCC brought about good antimicrobial behavior (both gram-positive and gram-negative) of the film. NCC incorporated poly(vinyl alcohol)/gellan-gum-based composite film exhibited increased mechanical properties and impedance behavior for improved ocular delivery of moxifloxacin.

An integrated technology for the absorption and utilization of CO2 in alkanolamine solution for the preparation of BaCO3 in a high gravity environment

In this study, an integrated technology is proposed for the absorption and utilization of CO2 in alkanolamine solution for the preparation of BaCO3 in a high gravity environment. The effects of absorbent type, high gravity factor, gas/liquid ratio, and initial BaCl2 concentration on the absorption rate and amount of CO2 and the preparation of BaCO3 are investigated. The results reveal that the absorption rate and amount of CO2 follow the order of ethyl alkanolamine (MEA) > diethanol amine (DEA) > N-methyldiethanolamine (MDEA), and thus MEA is the most effective absorbent for CO2 absorption. The absorption rate and amount of CO2 under high gravity are higher than that under normal gravity. Notably, the absorption rate at 75 min under high gravity is approximately 2 times that under normal gravity. This is because the centrifugal force resulting from the high-speed rotation of the packing can greatly increase gas-liquid mass transfer and micromixing. The particle size of BaCO3 prepared in the rotating packed bed is in the range of 57.2−89 nm, which is much smaller than that prepared in the bubbling reactor (>100.3 nm), and it also has higher purity (99.6 %) and larger specific surface area (14.119 m2/g). It is concluded that the high gravity technology has the potential to increase the absorption and utilization of CO2 in alkanolamine solution for the preparation of BaCO3. This study provides new insights into carbon emissions reduction and carbon utilization.