The Swelling Kinetics Study of Hydrogels Prepared by the Different Finesses Degrees of Eupatorium Adenophorum

2013 ◽  
Vol 690-693 ◽  
pp. 1615-1619
Author(s):  
Hai Bo Wen ◽  
Xin Gao ◽  
Heng Zhang

In this study the different finesses degree of the pulverized Eupatorium Adenophorum (EA) was evaluated as potential raw materials for the low-cost hydrogels whose the swelling behaviors were compared and studied at the same graft-copolymerization condition. The results are shown that the absorbency of EA hydrogels increased with decreasing the granule size of pulverized EA from 0.450mm to 0.063mm, while the swelling ratios gradually decreased with continuously reducing the particles size to 0.020mm, and the swelling exponents have been found to indicate non-Fickian mechanism for EA hydrogels at the all finesses range of 0.020~0.450mm. Moreover, to obtain better model for above 60% water uptake, the Beren-Hopfenberg differential model was applied, which also enabled to calculate the relaxation constants.

2013 ◽  
Vol 634-638 ◽  
pp. 2098-2105
Author(s):  
Hai Bo Wen ◽  
Xin Gao ◽  
Heng Zhang ◽  
Ke Li Chen

In this study Eupatorium adenophorum was evaluated as potential raw materials for Water-Absorbent Composite (WAC) synthesized with acrylic acid (AA) and acrylamide (AM) in aqueous medium. Factors, such as weight ratio of AA/AM to dry powdered Eupatorium adenophorum (DPEA), the amount of initiator and cross-linker, neutralization degree of AA, which influence water-absorbent capacity of WAC, were investigated. Additionally, the performances of WACs were appraised in term of water absorbency. The results showed that the nearly optimal WAC was obtained with absorbencies of 933 g/g in deionized water and 310 g/g in 0.9 wt% NaCl aqueous solution. Furthermore, the optimum super-absorbent has been proved with expectant polymerization structures and the morphological features via Fourier Transform Infrared Spectroscopy (FT-IR), X-Ray Diffraction (XRD) and Scanning Electric Microscopy (SEM).


2020 ◽  
Vol 4 (1) ◽  
pp. 41-48
Author(s):  
Teodoro Astorga Amatosa ◽  
Michael E. Loretero

Bamboo is a lightweight and high-strength raw materials that encouraged researchers to investigate and explore, especially in the field of biocomposite and declared as one of the green-technology on the environment as fully accountable as eco-products. This research was to assess the technical feasibility of making single-layer experimental Medium-Density Particleboard panels from the bamboo waste of a three-year-old (Dendrocalamus asper). Waste materials were performed to produce composite materials using epoxy resin (C21H25C105) from a natural treatment by soaking with an average of pH 7.6 level of sea-water. Three different types of MDP produced, i.e., bamboo waste strip MDP (SMDP), bamboo waste chips MDP (CMDP) and bamboo waste mixed strip-chips MDP (MMDP) by following the same process. The experimental panels tested for their physical-mechanical properties according to the procedures defined by ASTM D1037-12. Conclusively, even the present study shows properties of MDP with higher and comparable to other composite materials; further research must be given better attention as potential substitute to be used as hardwood materials, especially in the production, design, and construction usage.


2019 ◽  
Author(s):  
Yu Wang ◽  
Nachuan Yang ◽  
Yi Shuai ◽  
Yunpeng Zhang ◽  
Kanghua Chen

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1204
Author(s):  
Mengna Chen ◽  
Xuelong Chen ◽  
Caiyan Zhang ◽  
Baozheng Cui ◽  
Zewen Li ◽  
...  

One type of low-cost and eco-friendly organic‒inorganic superabsorbent composite (SAPC) was synthesized by free radical polymerization of acrylic acid (AA), starch (ST), sodium alginate (SA) and kaolin (KL) in aqueous solution. The structure and morphology of the SAPC were characterized by Fourier transform infrared spectrometer (FT-IR), scanning electron microscope (SEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The influence of different reaction conditions on water absorption of SAPC, i.e., SA and KL contents, AA neutralization degree (ND), potassium persulfate (KPS) and N, N′-methylenebisacrylamide (MBA) loading were systematically studied. Under the optimal synthesis conditions, very high water absorption of 1200 g/g was achieved. The swelling kinetic mechanism of SAPC was studied by pseudo-second order swelling kinetics model and Ritger‒Peppas model. The performances of SAPC under different environments were tested and results revealed that this new SAPC had excellent swelling capacity, high water retention, good salt tolerance in monovalent salt solution (NaCl solution) and good pH tolerance between 4 and 10.


Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2910
Author(s):  
Chaoyi Ding ◽  
Chun Liu ◽  
Ligang Zhang ◽  
Di Wu ◽  
Libin Liu

The high cost of development and raw materials have been obstacles to the widespread use of titanium alloys. In the present study, the high-throughput experimental method of diffusion couple combined with CALPHAD calculation was used to design and prepare the low-cost and high-strength Ti-Al-Cr system titanium alloy. The results showed that ultra-fine α phase was obtained in Ti-6Al-10.9Cr alloy designed through the pseudo-spinodal mechanism, and it has a high yield strength of 1437 ± 7 MPa. Furthermore, application of the 3D strength model of Ti-6Al-xCr alloy showed that the strength of the alloy depended on the volume fraction and thickness of the α phase. The large number of α/β interfaces produced by ultra-fine α phase greatly improved the strength of the alloy but limited its ductility. Thus, we have demonstrated that the pseudo-spinodal mechanism combined with high-throughput diffusion couple technology and CALPHAD was an efficient method to design low-cost and high-strength titanium alloys.


2021 ◽  
Author(s):  
Junzhen Ren ◽  
Pengqing Bi ◽  
Jianqi Zhang ◽  
Jiao Liu ◽  
Jingwen Wang ◽  
...  

Abstract Developing photovoltaic materials with simple chemical structures and easy synthesis still remains a major challenge in the industrialization process of organic solar cells (OSCs). Herein, an ester substituted poly(thiophene vinylene) derivative, PTVT-T, was designed and synthesized in very few steps by adopting commercially available raw materials. The ester groups on the thiophene units enable PTVT-T to have a planar and stable conformation. Moreover, PTVT-T presents a wide absorption band and strong aggregation effect in solution, which are the key characteristics needed to realize high performance in non-fullerene-acceptor (NFA)-based OSCs. We then prepared OSCs by blending PTVT-T with three representative fullerene- and NF-based acceptors, PC71BM, IT-4F and BTP-eC9. It was found that PTVT-T can work well with all the acceptors, showing great potential to match new emerging NFAs. Particularly, a remarkable power conversion efficiency of 16.20% is achieved in a PTVT-T:BTP-eC9-based device, which is the highest value among the counterparts based on PTV derivatives. This work demonstrates that PTVT-T shows great potential for the future commercialization of OSCs.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1186
Author(s):  
Carmen S. Favaro-Trindade ◽  
Fernando E. de Matos Junior ◽  
Paula K. Okuro ◽  
João Dias-Ferreira ◽  
Amanda Cano ◽  
...  

Nanoencapsulation via spray cooling (also known as spray chilling and spray congealing) has been used with the aim to improve the functionality, solubility, and protection of drugs; as well as to reduce hygroscopicity; to modify taste and odor to enable oral administration; and many times to achieve a controlled release profile. It is a relatively simple technology, it does not require the use of low-cost solvents (mostly associated to toxicological risk), and it can be applied for lipid raw materials as excipients of oral pharmaceutical formulations. The objective of this work was to revise and discuss the advances of spray cooling technology, with a greater emphasis on the development of lipid micro/nanoparticles to the load of active pharmaceutical ingredients for oral administration.


2016 ◽  
Author(s):  
A. Ribeiro ◽  
C. Vilarinho ◽  
J. Araújo ◽  
J. Carvalho

The increasing of world population, industrialization and global consuming, existing market products existed in the along with diversification of raw materials, are responsible for an exponential increase of wastes. This scenario represents loss of resources and ultimately causes air, soils and water pollution. Therefore, proper waste management is currently one of the major challenges faced by modern societies. Textile industries represents, in Portugal, almost 10% of total productive transforming sector and 19% of total employments in the sector composed by almost 7.000 companies. One of the main environmental problems of textile industries is the production of significant quantities of wastes from its different processing steps. According to the Portuguese Institute of Statistics (INE) these industries produce almost 500.000 tons of wastes each year, with the textile cotton waste (TCW) being the most expressive. It was estimated that 4.000 tons of TCW are produced each year in Portugal. In this work an integrated TCW valorisation procedure was evaluated, firstly by its thermal and energetic valorisation with slow pyrolysis followed by the utilization of biochar by-product, in lead and chromium synthetic wastewater decontamination. Pyrolysis experiments were conducted in a small scale rotating pyrolysis reactor with 0.1 m3 of total capacity. Results of pyrolysis experiments showed the formation of 0,241 m3 of biogas for each kilogram of TCW. Results also demonstrated that the biogas is mostly composed by hydrogen (22%), methane (14 %), carbon monoxide (20%) and carbon dioxide (12%), which represents a total high calorific value of 12.3 MJ/Nm3. Regarding biochar, results of elemental analysis demonstrated a high percentage of carbon driving its use as low cost adsorbent. Adsorption experiments were conducted with lead and chromium synthetic wastewaters (25, 50 and 100 mg L−1) in batch vessels with controlled pH. It was evaluated the behaviour of adsorption capacity and removal rate of each metal during 120 minutes of contact time using 5, 10 and 50 g L−1 of adsorbent dosage. Results indicated high affinity of adsorbent with each tested metal with 78% of removal rate in chromium and 95% in lead experiments. This suggests that biochar from TCW pyrolysis may be appropriated to wastewaters treatment, with high contents of heavy metals and it can be an effective alternative to activated carbon.


2000 ◽  
Vol 15 (1) ◽  
pp. 2-8 ◽  
Author(s):  
N.C. Wagner ◽  
S. Ramaswamy ◽  
U. Tschirner

AbstractA pre-economic feasibility study was undertaken to determine the potential of cereal straw for industrial utilization in Minnesota. Specifically, utilizing straw for pulp and paper manufacture was of interest. The availability of cereal straw fiber supplies at various locations across the state of Minnesota, along with pre-processing issues such as transportation, harvesting, handling, and storage, are discussed and priced. The greatest economic advantage of straw for industrial use appears to be the low cost of the raw material compared to traditional raw materials. This also provides an excellent opportunity for additional income for farmers. The methodology and information provided here should be helpful in evaluating the feasibility of utilizing straw for other industrial purposes in other parts of the world. However, in some Third World countries, long-standing on-farm, traditional uses of cereal straws for fuel, fiber, and animal feed may limit their availability for industrial utilization.


2013 ◽  
Vol 787 ◽  
pp. 382-387
Author(s):  
Li Zhou ◽  
Yuan Kui Ding ◽  
Pai Feng Luo

A facile low-cost non-vacuum process for fabrication of high quality CuInSe2(CIS) films is described, which indicates a promising way for the application in thin film solar cells. First, citrate-capped Cu11In9alloy nanoparticles are synthesized by hot-injection method after a system research on the different reaction time and Cu-In ratio of the raw materials. From the TEM and XRD results, we can see that uniform spherical nanoparticles with dominant Cu11In9phase and less particle-to-particle agglomeration are successfully achieved in this study. Then, employing spray and RTP selenization process, high quality CIS films with dense and big grains are obtained, which show the single chalcopyrite structure and the preferred (112) orientation. An energy band gap about 1.01 eV is measured through the absorption spectroscopy measurement in our work.


Sign in / Sign up

Export Citation Format

Share Document