25 results on '"Xianhui Zhao"'
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2. Review on Nonconventional Fibrillation Methods of Producing Cellulose Nanofibrils and Their Applications
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Xianhui Zhao, Donna Johnson, Douglas J. Gardner, Katie Copenhaver, Colleen C. Walker, Soydan Ozcan, Lu Wang, Jinwu Wang, Yousoo Han, Susan Mackay, Kai Li, David J. Neivandt, Meghan E. Lamm, and Brandon Dixon
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Fibrillation ,Materials science ,Polymers and Plastics ,Production cost ,Nanofibers ,Biomass ,Bioengineering ,Nanotechnology ,Lower energy ,Biomaterials ,chemistry.chemical_compound ,chemistry ,Materials Chemistry ,medicine ,medicine.symptom ,Cellulose - Abstract
The production of cellulose nanofibrils (CNFs) continues to receive considerable attention because of their desirable material characteristics for a variety of consumer applications. There are, however, challenges that remain in transitioning CNFs from research to widespread adoption in the industrial sectors, including production cost and material performance. This Review covers CNFs produced from nonconventional fibrillation methods as a potential alternative solution. Pretreating biomass by biological, chemical, mechanical, or physical means can render plant feedstocks more facile for processing and thus lower energy requirements to produce CNFs. CNFs from nonconventional fibrillation methods have been investigated for various applications, including films, composites, aerogels, and Pickering emulsifiers. Continued research is needed to develop protocols to standardize the characterization (e.g., degree of fibrillation) of the lignocellulosic fibrillation processes and resulting CNF products to make them more attractive to the industry for specific product applications.
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- 2021
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3. High-Strength Polylactic Acid (PLA) Biocomposites Reinforced by Epoxy-Modified Pine Fibers
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Erin Webb, Gregory S. Larsen, Ryan S. Ginder, Mehdi Tajvidi, Douglas J. Gardner, Soydan Ozcan, Xianhui Zhao, Lu Wang, Kai Li, Yu Wang, Halil Tekinalp, and Daniel Rasmussen
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Materials science ,Renewable Energy, Sustainability and the Environment ,General Chemical Engineering ,Stiffness ,02 engineering and technology ,General Chemistry ,Epoxy ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Polylactic acid ,chemistry ,visual_art ,Ultimate tensile strength ,visual_art.visual_art_medium ,medicine ,Environmental Chemistry ,Composite material ,medicine.symptom ,Biocomposite ,0210 nano-technology ,Natural fiber - Abstract
The stiffness and tensile strength of biopolymers (e.g., polylactic acid (PLA)) are less than desirable for load-bearing applications in their neat form. The use of natural fibers as reinforcements...
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- 2020
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4. The Use of Molecular Subtypes for Precision Therapy of Recurrent and Metastatic Gastrointestinal Stromal Tumor
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Heli Liu, Xianhui Zhao, Bin Li, Peng Liu, Fengbo Tan, and Tianxiang Lei
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0301 basic medicine ,Oncology ,medicine.medical_specialty ,medicine.drug_class ,PDGFRA ,Tyrosine-kinase inhibitor ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Regorafenib ,Internal medicine ,medicine ,Pharmacology (medical) ,Stromal tumor ,Sunitinib ,business.industry ,Imatinib ,Precision medicine ,digestive system diseases ,030104 developmental biology ,chemistry ,Tumor progression ,030220 oncology & carcinogenesis ,business ,medicine.drug - Abstract
Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumor in the digestive tract. Tyrosine kinase inhibitors (TKIs), represented by imatinib, sunitinib, and regorafenib, have become the main treatment for recurrent and metastatic GISTs. With the wide application of mutation analysis and the precision medicine, molecular characteristics have been determined that not only predict the prognosis of patients with recurrent and metastatic GISTs, but also are closely related to the efficacy of first-, second- and third-line TKIs for GISTs, as well as other TKIs. Despite the significant effects of TKIs, the emergence of primary and secondary resistance ultimately leads to treatment failure and tumor progression. Currently, due to the signal transmission of KIT/PDGFRA during onset and tumor progression, strategies to counteract drug resistance include the replacement of TKIs and the development of new drugs that are directed towards carcinogenic mutations. In addition, it is also the embodiment of precision medicine for GISTs to explore new carcinogenic mechanisms and develop new drugs relying on new biotechnology. Surgery can benefit specific patients but its major purpose is to diminish the resistant clones. However, the prognosis of recurrent and metastatic patients is still unsatisfactory. Therefore, it is worth paying attention to how to maximize the benefits for patients.
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- 2020
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5. Long-Term Physical and Mechanical Properties and Microstructures of Fly-Ash-Based Geopolymer Composite Incorporating Carbide Slag
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Boyu Zhou, Jiashuo Zhang, Haoyu Wang, Linlin Jiang, Xianhui Zhao, and Lingchao Meng
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Technology ,Materials science ,porosity ,microstructure ,Article ,Carbide ,chemistry.chemical_compound ,Flexural strength ,General Materials Science ,Composite material ,Sodium aluminosilicate ,Microscopy ,QC120-168.85 ,Aggregate (composite) ,QH201-278.5 ,Engineering (General). Civil engineering (General) ,Microstructure ,fly-ash-based geopolymer ,TK1-9971 ,Geopolymer ,shrinkage ,Descriptive and experimental mechanics ,chemistry ,Fly ash ,Calcium silicate ,Electrical engineering. Electronics. Nuclear engineering ,TA1-2040 ,carbide slag ,strength - Abstract
The long-term property development of fly ash (FA)-based geopolymer (FA–GEO) incorporating industrial solid waste carbide slag (CS) for up to 360 d is still unclear. The objective of this study was to investigate the fresh, physical, and mechanical properties and microstructures of FA–GEO composites with CS and to evaluate the effects of CS when the composites were cured for 360 d. FA–GEO composites with CS were manufactured using FA (as an aluminosilicate precursor), CS (as a calcium additive), NaOH solution (as an alkali activator), and standard sand (as a fine aggregate). The fresh property and long-term physical properties were measured, including fluidity, bulk density, porosity, and drying shrinkage. The flexural and compressive strengths at 60 d and 360 d were tested. Furthermore, the microstructures and gel products were characterized by scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). The results show that the additional 20.0% CS reduces the fluidity and increases the conductivity of FA–GEO composites. Bulk densities were decreased, porosities were increased, and drying shrinkages were decreased as the CS content was increased from 0.0% to 20.0% at 360 d. Room temperature is a better curing condition to obtain a higher long-term mechanical strength. The addition of 20.0% CS is more beneficial to the improvement of long-term flexural strength and toughness at room temperature. The gel products in CS–FA–GEO with 20.0% CS are mainly determined as the mixtures of sodium aluminosilicate (N–A–S–H) gel and calcium silicate hydration (C–S–H) gel, besides the surficial pan-alkali. The research results provide an experimental basis for the reuse of CS in various scenarios.
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- 2021
6. Amphipathic Binder Integrating Ultrathin and Highly Ion-Conductive Sulfide Membrane for Cell-Level High-Energy-Density All-Solid-State Batteries
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Wentao Liang, Soydan Ozcan, Alexander Anderson, Daxian Cao, Xianhui Zhao, Xiao Sun, Ercan Cakmak, Ying Wang, Hongli Zhu, and Qiang Li
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chemistry.chemical_classification ,Materials science ,Sulfide ,Mechanical Engineering ,Conductance ,chemistry.chemical_element ,Electrolyte ,chemistry.chemical_compound ,Membrane ,chemistry ,Ethyl cellulose ,Chemical engineering ,Mechanics of Materials ,Gravimetric analysis ,General Materials Science ,Thermal stability ,Lithium - Abstract
Current sulfide solid-state electrolyte (SE) membranes utilized in all-solid-state lithium batteries (ASLBs) have a high thickness (0.5-1.0 mm) and low ion conductance (
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- 2021
7. Synthesis, Characterization, and Utilization of a Lignin-Based Adsorbent for Effective Removal of Azo Dye from Aqueous Solution
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Charles M. Cai, Mi Li, Yun-Yan Wang, Miguel Toro-González, Arthur J. Ragauskas, Brent Scheidemantle, Xianzhi Meng, Priyanka Singh, Xianhui Zhao, Soydan Ozcan, Yunqiao Pu, and Charles E. Wyman
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Aqueous solution ,General Chemical Engineering ,technology, industry, and agriculture ,General Chemistry ,CE-CERT ,Article ,Characterization (materials science) ,Industrial wastewater treatment ,chemistry.chemical_compound ,Chemistry ,Adsorption ,chemistry ,Chemical engineering ,Lignin ,QD1-999 - Abstract
How to effectively remove toxic dyes from the industrial wastewater using a green low-cost lignocellulose-based adsorbent, such as lignin, has become a topic of great interest but remains quite challenging. In this study, cosolvent-enhanced lignocellulosic fractionation (CELF) pretreatment and Mannich reaction were combined to generate an aminated CELF lignin which is subsequently applied for removal of methylene blue and direct blue (DB) 1 dye from aqueous solution. 31P NMR was used to track the degree of amination, and an orthogonal design was applied to determine the relationship between the extent of amination and reaction parameters. The physicochemical, morphological, and thermal properties of the aminated CELF lignin were characterized to confirm the successful grafting of diethylenetriamine onto the lignin. The aminated CELF lignin proved to be an effective azo dye-adsorbent, demonstrating considerably enhanced dye decolorization, especially toward DB 1 dye (>90%). It had a maximum adsorption capacity of DB 1 dye of 502.7 mg/g, and the kinetic study suggested the adsorption process conformed to a pseudo-second-order kinetic model. The isotherm results also showed that the modified lignin-based adsorbent exhibited monolayer adsorption. The adsorbent properties were mainly attributed to the incorporated amine functionalities as well as the increased specific surface area of the aminated CELF lignin.
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- 2020
8. Poly(lactic acid) Toughening through Chain End Engineering
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Kai Li, Matthew Rowe, Tianyu Li, Xianhui Zhao, Yu Wang, Halil Tekinalp, and Soydan Ozcan
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Polyester ,chemistry.chemical_compound ,Polymers and Plastics ,Chain (algebraic topology) ,chemistry ,Chemical engineering ,Process Chemistry and Technology ,Organic Chemistry ,Toughening ,Lactic acid - Abstract
The intrinsic brittleness of poly(lactic acid) (PLA) has hindered its widespread use in many structural applications. Various strategies have been developed to toughen PLA; however, most of the met...
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- 2019
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9. Properties and Hydration Mechanism of Soda Residue-Activated Ground Granulated Blast Furnace Slag Cementitious Materials
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Xianhui Zhao, Yonghui Lin, and Dongqiang Xu
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chloride binding ,Ettringite ,Technology ,Materials science ,Absorption of water ,microstructure ,0211 other engineering and technologies ,02 engineering and technology ,Chloride ,Article ,chemistry.chemical_compound ,021105 building & construction ,medicine ,General Materials Science ,Porosity ,Microscopy ,QC120-168.85 ,ground granulated blast furnace slag ,QH201-278.5 ,021001 nanoscience & nanotechnology ,Alkali metal ,Engineering (General). Civil engineering (General) ,TK1-9971 ,cement paste ,Compressive strength ,Chemical engineering ,chemistry ,Descriptive and experimental mechanics ,Ground granulated blast-furnace slag ,alkali activation ,hydration products ,Cementitious ,Electrical engineering. Electronics. Nuclear engineering ,TA1-2040 ,0210 nano-technology ,medicine.drug ,soda residue - Abstract
Soda residue (SR), an industrial solid waste, pollutes the environment due to its high alkalinity and chloride ion content. SR can be used as an alkali activator of ground granulated blast furnace slag (GGBFS). This study investigated the effects of four types of SR-activated GGBFS cementitious materials (pastes) with different mass ratios of SR to GGBFS (8:92, 16:84, 24:76, 34:68) on the physical properties, mechanical strength, and chloride binding capacity. The hydration mechanism of the pastes was also studied. Results showed that with the increasing addition of SR, the density of the pastes decreased, and more white aggregates of SR appeared causing the increase of water absorption and porosity of the pastes. The pastes with 16% SR addition had the maximum compressive strength (34.1 MPa, 28 d), so the optimum proportion of SR addition in the pastes was 16%. With the increases of SR addition, the amount of chloride element in the initial pastes increases. When the proportion of SR addition is 8%, the mass percentage of free chloride ion in the pastes at 28 d is 0.13%. The main hydration products of the pastes were C–S–H gels, ettringite, and Friedel’s salt, and the amount of ettringite varied with the amount of SR addition and curing time.
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- 2021
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10. Performance Optimization and Characterization of Soda Residue-Fly Ash Geopolymer Paste for Goaf Backfill: Beta-Hemihydrate Gypsum Alternative to Sodium Silicate
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Xianhui Zhao, Boyu Zhou, Han Gao, Haoyu Wang, and Yonghui Lin
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Gypsum ,Materials science ,Scanning electron microscope ,microstructure ,0211 other engineering and technologies ,paste backfill ,Sodium silicate ,02 engineering and technology ,engineering.material ,lcsh:Technology ,Article ,chemistry.chemical_compound ,geopolymer ,alternatives ,soda residue ,gel product ,021105 building & construction ,General Materials Science ,Fourier transform infrared spectroscopy ,lcsh:Microscopy ,lcsh:QC120-168.85 ,lcsh:QH201-278.5 ,lcsh:T ,021001 nanoscience & nanotechnology ,Microstructure ,Geopolymer ,Compressive strength ,chemistry ,Chemical engineering ,lcsh:TA1-2040 ,Fly ash ,engineering ,lcsh:Descriptive and experimental mechanics ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,0210 nano-technology ,lcsh:Engineering (General). Civil engineering (General) ,lcsh:TK1-9971 - Abstract
Solid waste soda residue (SR), as an industrial pollutant of water, air and soil environment, can be utilized to prepare the low-calcium fly ash (FFA)-based geopolymer paste activated by sodium silicate (NS) solution for goaf backfill. However, the high addition of NS produces the high cost and high strength of synthesized backfill material in the previous study. The objective of this research is to investigate the cost optimization method and performance evaluation of SR-FFA-based geopolymer backfill paste. The alkaline beta-hemihydrate gypsum (BHG) alternative to partial NS was proposed. Scanning electron microscopy (SEM), X-ray diffraction (XRD) as well as Fourier transform infrared spectrometer (FTIR) tests were performed to clarify the role of BHG and evaluate the microstructures and products of backfill pastes. The results show that 10% BHG alternative ratios effectively improve fluidity, setting time and compressive strength to satisfy the performance requirement of goaf backfill material. The gel products in the optimal backfill paste C4 with 10% BHG alternative ratios are determined as the coexistence of C-S-H gel, (N,C)-A-S-H gel and CaSO4·2H2O at 28 d. The research results can make extensive utilization of SR and FFA in cemented paste backfill to synthesize cleaner material at a larger scale.
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- 2020
11. Surface-modified and oven-dried microfibrillated cellulose reinforced biocomposites: Cellulose network enabled high performance
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Jun Qu, Soydan Ozcan, Vlastimil Kunc, Kai Li, Ercan Cakmak, Jon Phipps, Denver Mcgrady, Xianhui Zhao, Sean Ireland, Tolga Aytug, Darby Ker, Xin He, and Halil Tekinalp
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Materials science ,Vinyl Compounds ,Polymers and Plastics ,Surface Properties ,Polyesters ,Modulus ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Nanocellulose ,Nanomaterials ,Nanocomposites ,chemistry.chemical_compound ,Polylactic acid ,Elastic Modulus ,Tensile Strength ,Ultimate tensile strength ,Materials Testing ,Materials Chemistry ,Humans ,Cellulose ,Desiccation ,chemistry.chemical_classification ,Calorimetry, Differential Scanning ,Organic Chemistry ,Water ,Polymer ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,chemistry ,Chemical engineering ,Thermogravimetry ,Microscopy, Electron, Scanning ,Surface modification ,0210 nano-technology ,Laurates - Abstract
Microfibrillated cellulose (MFC) is widely used as a reinforcement filler for biocomposites due to its unique properties. However, the challenge of drying MFC and the incompatibility between nanocellulose and polymer matrix still limits the mechanical performance of MFC-reinforced biocomposites. In this study, we used a water-based transesterification reaction to functionalize MFC and explored the capability of oven-dried MFC as a reinforcement filler for polylactic acid (PLA). Remarkably, this oven-dried, vinyl laurate-modified MFC improved the tensile strength by 38 % and Young's modulus by 71 % compared with neat PLA. Our results suggested improved compatibility and dispersion of the fibrils in PLA after modification. This study demonstrated that scalable water-based surface modification and subsequent straightforward oven drying could be a facile method for effectively drying cellulose nanomaterials. The method helps significantly disperse fibrils in polymers and enhances the mechanical properties of microfibrillar cellulose-reinforced biocomposites.
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- 2020
12. Critical review of FDM 3D printing of PLA biocomposites filled with biomass resources, characterization, biodegradability, upcycling and opportunities for biorefineries
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Samarthya Bhagia, Rastislav Lagaňa, Arthur J. Ragauskas, Ruchi Agrawal, Soydan Ozcan, Alok Satlewal, Chang Geun Yoo, Kamlesh Bornani, Yunqiao Pu, Meher Bhagia, Vlastimil Kunc, Xianhui Zhao, and Jaroslav Ďurkovič
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chemistry.chemical_classification ,Materials science ,Thermoplastic ,Fused deposition modeling ,business.industry ,Biomass ,3D printing ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,law.invention ,chemistry.chemical_compound ,Upcycling ,chemistry ,Polylactic acid ,law ,General Materials Science ,Hemicellulose ,Cellulose ,0210 nano-technology ,business - Abstract
3D printing by fused deposition modeling (FDM) is an advanced additive manufacturing technology for making thermoplastic-based structures. Several studies have recently investigated 3D printing of polylactic acid (PLA) with biomass resources like cellulose, hemicellulose, lignin and whole biomass. Such biodegradable composites are better for the environment and can be used to replace non-biodegradable composites in a variety of applications. Therefore, a deep understanding of printing such biocomposites is needed for supporting such manufacturing. Recent developments focused on FDM printing of PLA filled with biomass resources have been critically reviewed to reveal the intricate aspects of manufacturing of such materials and characterization of the changes caused by biomass-based fillers. Properties of high molecular weight PLA, essentials of printing with PLA and conditions for filament extrusion and printing of biocomposites are discussed. Characterization results from mechanical testing, thermal analysis, viscoelastic properties, imaging and spectroscopy are reviewed for understanding the impact of filling biomass resources in PLA by printing. The latter sections discuss applications, upcycling & recycling and future opportunities for biorefineries.
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- 2021
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13. Converting Alkali Lignin to Biofuels over NiO/HZSM‐5 Catalysts Using a Two‐Stage Reactor
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Xianhui Zhao, Lin Wei, Shouyun Cheng, James Julson, and Ethan Kadis
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chemistry.chemical_classification ,020209 energy ,General Chemical Engineering ,Inorganic chemistry ,Non-blocking I/O ,02 engineering and technology ,General Chemistry ,7. Clean energy ,Redox ,6. Clean water ,Industrial and Manufacturing Engineering ,Catalysis ,chemistry.chemical_compound ,Hydrocarbon ,chemistry ,Biofuel ,Yield (chemistry) ,0202 electrical engineering, electronic engineering, information engineering ,Lignin ,Pyrolysis - Abstract
A series of NiO/HZSM-5 catalysts were used to convert alkali lignin to hydrocarbon biofuels in a two-stage catalytic pyrolysis system. The results indicated that all NiO/HZSM-5 catalysts reduced the content of undesirable phenols, furans, and alcohols of the biofuel compared to non-catalytic treatment. The NiO/HZSM-5 catalyst with the lowest amount of NiO generated the highest biofuel yield in all catalytic treatments, and it also produced biofuel with the highest content of hydrocarbons. The emission of carbon oxides (CO and CO2) increased in the treatments with higher-NiO loading HZSM-5 due to the redox reaction between NiO and the oxygenated compounds in the bio-oil. Ni2SiO4 was generated in the used NiO/HZSM-5 catalysts during the high-temperature pyrolysis process.
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- 2017
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14. Pyrroloquinoline quinone attenuates isoproterenol hydrochloride‑induced cardiac hypertrophy in AC16 cells by inhibiting the NF‑κB signaling pathway
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Junwei Shen, Xianhui Zhao, Zhensheng Dai, Yueling Jin, Yajie Zhou, and Junru Wen
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0301 basic medicine ,PQQ Cofactor ,Cardiomegaly ,Pharmacology ,Cell Line ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Pyrroloquinoline quinone ,Atrial natriuretic peptide ,isoproterenol hydrochloride ,Genetics ,Humans ,Myocyte ,Myocytes, Cardiac ,reactive oxygen species ,Chemistry ,pyrroloquinoline quinone ,cardiac hypertrophy ,Isoproterenol ,NF-kappa B ,Articles ,General Medicine ,Brain natriuretic peptide ,030104 developmental biology ,Apoptosis ,030220 oncology & carcinogenesis ,Phosphorylation ,Signal transduction ,Intracellular ,Signal Transduction - Abstract
Pyrroloquinoline quinone (PQQ) is a naturally occurring redox co‑factor that functions as an essential nutrient and antioxidant, and has been reported to exert potent anti‑inflammatory effects. However, the therapeutic potential of PQQ for isoproterenol hydrochloride (Iso)‑induced cardiac hypertrophy has not yet been explored, at least to the best of our knowledge. In the present study, the anti‑inflammatory effects of PQQ were investigated in Iso‑treated AC16 cells, a myocardial injury cellular model characterized by an increase in the apparent surface area of the cells and the activation of intracellular cardiac hypertrophy‑associated proteins. The results revealed that pre‑treatment with PQQ significantly inhibited the expression of cardiac hypertrophy marker proteins, such as atrial natriuretic peptide, brain natriuretic peptide and β‑myosin heavy chain. PQQ also inhibited the activation of the nuclear factor (NF)‑κB signaling pathway in Iso‑treated AC16 cells, thus inhibiting the nuclear translocation of NF‑κB and reducing the phosphorylation levels of p65. On the whole, the findings of this study suggest that PQQ may be a promising therapeutic agent for effectively reversing the progression of cardiac hypertrophy.
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- 2020
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15. Development of a bifunctional Ni/HZSM-5 catalyst for converting prairie cordgrass to hydrocarbon biofuel
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Lin Wei, Shouyun Cheng, and Xianhui Zhao
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chemistry.chemical_classification ,Renewable Energy, Sustainability and the Environment ,020209 energy ,Energy Engineering and Power Technology ,Fraction (chemistry) ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Mass spectrometry ,Catalysis ,chemistry.chemical_compound ,Fuel Technology ,Hydrocarbon ,Nuclear Energy and Engineering ,chemistry ,Biofuel ,0202 electrical engineering, electronic engineering, information engineering ,Organic chemistry ,Gas chromatography ,Gasoline ,0210 nano-technology ,Bifunctional ,Nuclear chemistry - Abstract
Ni/HZSM-5 catalysts were prepared using the impregnation method. The HZSM-5 and impregnated Ni/HZSM-5 catalysts were characterized by Brunauer–Emmett–Teller and X-ray diffraction. The HZSM-5 and Ni/HZSM-5 catalysts were used for prairie cordgrass (PCG) thermal conversion in a two-stage catalytic pyrolysis system. The products contained gas, bio-oil, and bio-char. The gas and bio-oil were analyzed by gas chromatography and gas chromatography–mass spectrometry separately. Higher heating values and elemental composition of bio-char were determined. The results indicated that 12% Ni/HZSM-5 treatment yielded the highest amount of gasoline fraction for hydrocarbons and showed a robust ability to upgrade bio-oil vapor.
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- 2016
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16. Upgrading pine sawdust pyrolysis oil to green biofuels by HDO over zinc-assisted Pd/C catalyst
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James Julson, Shouyun Cheng, Yuhe Cao, Lin Wei, Xianhui Zhao, Yinbin Huang, and Zhengrong Gu
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chemistry.chemical_classification ,Renewable Energy, Sustainability and the Environment ,020209 energy ,Energy Engineering and Power Technology ,02 engineering and technology ,Coke ,021001 nanoscience & nanotechnology ,chemistry.chemical_compound ,Fuel Technology ,Hydrocarbon ,Nuclear Energy and Engineering ,Chemical engineering ,chemistry ,Biofuel ,Pyrolysis oil ,visual_art ,0202 electrical engineering, electronic engineering, information engineering ,visual_art.visual_art_medium ,Organic chemistry ,Sawdust ,0210 nano-technology ,Hydrodeoxygenation ,Pyrolysis ,Syngas - Abstract
Upgrading pyrolysis oil by hydrodeoxygenation (HDO) is a promising route for the production of advanced biofuels. The proper reaction conditions and catalysts are important for the success of this process. Previously our research group investigated the ratio of Zn and Pd on the synergistic effect for HDO bio-oil upgrading. This present research focuses on determining the optimal reaction conditions for HDO conversion of pyrolysis oil produced from pine sawdust. Temperatures of 150, 200 and 250 °C and hydrogen pressures of 1.38, 2.76 and 4.14 MPa were evaluated. Syngas, liquids and coke were the primary products evaluated. Syngas was characterized using a Gas chromatography (GC). The liquids were characterized using a Gas chromatography–mass spectrometry (GC–MS). Increasing reaction temperature resulted in increased coke yields. Treatment at 250 °C and 1.38 MPa resulted in the highest hydrocarbon content (6.06%). The treatment at 200 °C and 1.38 MPa produced the largest amounts of hydrocarbons in C6–C12 range (5.07%). The physicochemical characterizations further support the GCMS results. Syngas analysis revealed that higher hydrogen pressure leads to increased hydrogen consumption and results in more oxy-compounds conversion to hydrocarbons. The syngas analysis also supports the liquid analysis result.
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- 2016
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17. Effects of cold press operating conditions on vegetable oil fatty acid profiles
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Lin Wei, Xianhui Zhao, and James Julson
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food.ingredient ,Waste management ,Renewable Energy, Sustainability and the Environment ,business.industry ,020209 energy ,Vegetable oil refining ,Residual oil ,02 engineering and technology ,010501 environmental sciences ,Oil mill ,Jet fuel ,Pulp and paper industry ,01 natural sciences ,Renewable energy ,chemistry.chemical_compound ,food ,Vegetable oil ,chemistry ,0202 electrical engineering, electronic engineering, information engineering ,Environmental science ,Petroleum ,Canola ,business ,0105 earth and related environmental sciences - Abstract
Although most of jet fuels are currently made from petroleum, nonfood oilseeds such as flax and canola seeds may be an alternative for renewable jet fuel production in the near future. Vegetable oils produced from those oilseeds can be upgraded to liquid hydrocarbons to produce renewable jet fuels. The production efficiency and cost are heavily relied on the vegetable oil fatty acid profile (FAP). Previous research indicated that vegetable oil FAP is affected by oilseed species and oil extraction conditions. Cold press oil extractions from flax and canola seeds were conducted. The effect of the frequency controlling the screw rotating speed on the oil extraction efficiency and quality was discussed. Characterization of the vegetable oils produced, including density, pH value, viscosity, moisture, element component, heating value and FAP, was carried out. The residual oil contents left in the cold press meals were also determined. The results show that the oil extraction efficiency of oilseeds incr...
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- 2016
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18. Resistance of Soda Residue–Fly Ash Based Geopolymer Mortar to Acid and Sulfate Environments
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Xianhui Zhao, Han Gao, Haoyu Wang, Boyu Zhou, and Yonghui Lin
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Materials science ,microstructure ,0211 other engineering and technologies ,Infrared spectroscopy ,02 engineering and technology ,lcsh:Technology ,Article ,chemistry.chemical_compound ,021105 building & construction ,General Materials Science ,Fourier transform infrared spectroscopy ,Sulfate ,lcsh:Microscopy ,geopolymer ,lcsh:QC120-168.85 ,lcsh:QH201-278.5 ,lcsh:T ,compressive strength ,021001 nanoscience & nanotechnology ,Microstructure ,chemical attack ,Geopolymer ,fly ash ,Compressive strength ,soda residue ,chemistry ,Chemical engineering ,lcsh:TA1-2040 ,Fly ash ,lcsh:Descriptive and experimental mechanics ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,Mortar ,lcsh:Engineering (General). Civil engineering (General) ,0210 nano-technology ,lcsh:TK1-9971 - Abstract
The early mechanical performances of low-calcium fly ash (FFA)-based geopolymer (FFA–GEO) mortar can be enhanced by soda residue (SR). However, the resistance of SR–FFA–GEO mortar to acid or sulfate environments is unclear, owing to the various inorganic calcium salts in SR. The aim of this study was to investigate the long-term mechanical strengths of up to 360 d and evaluate the resistance of SR–FFA–GEO mortar to 5% HCl and 5% Na2SO4 environments through the losses in compressive strength and mass. Scanning Electron Microscopy (SEM), Energy-Dispersive Spectroscopy (EDS) and Fourier Transform Infrared Spectrometer (FTIR) experiments were conducted for the SR–FFA–GEO mortars, both before and after chemical attack, to clarify the attack mechanism. The results show that the resistances of the SR–FFA–GEO mortar with 20% SR (namely M10) to 5% HCl and 5% Na2SO4 environments are superior to those of cement mortar. The environmental HCl reacts with the calcites in SR to produce CaCl2, CO2 and H2O to form more pores under HCl attack, and the environmental Na+ cations from Na2SO4 go into Si-O-Al network structure, to further enhance the strength of mortar under Na2SO4 attack. These results provide the experimental basis for the durability optimization of SR–FFA–GEO mortars.
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- 2021
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19. Synthesis and characterization of fly ash geopolymer paste for goaf backfill: Reuse of soda residue
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Li Wang, Chunyuan Liu, Boyu Zhou, Xianhui Zhao, Youcai Liu, Qin Zhu, and Liming Zuo
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Materials science ,Renewable Energy, Sustainability and the Environment ,Scanning electron microscope ,020209 energy ,Strategy and Management ,05 social sciences ,Infrared spectroscopy ,02 engineering and technology ,Microstructure ,Industrial and Manufacturing Engineering ,Geopolymer ,chemistry.chemical_compound ,Compressive strength ,Chemical engineering ,chemistry ,Fly ash ,Calcium silicate ,050501 criminology ,0202 electrical engineering, electronic engineering, information engineering ,Fourier transform infrared spectroscopy ,0505 law ,General Environmental Science - Abstract
Soda residue (SR), an industrial Ca-containing solid waste, threatens and pollutes the coastal ecological environment in China. To promote the resource recycling of soda residue, this paper proposes the synthesis method and performance evaluation of fly ash-based geopolymer paste using soda residue for goaf backfill. The pre-treatment of SR and the solid-liquid mixing technique were determined, and the optimal mixing proportion of the paste backfill material was selected by orthogonal test through the fluidity, setting time and compressive strength. Meanwhile, the long-term compressive strengths of hardened paste and control were measured to clarify the role of soda residue in backfill paste. To evaluate the microstructure and products of optimal backfill paste, X-ray diffraction (XRD) tests was conducted to analyze mineralogical phases. Then, scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy (EDS) were used to investigate the morphology and elemental composition of products. Thereafter, fourier transform infrared spectrometer (FTIR) and 29Si nuclear magnetic resonance (29Si NMR) were performed to characterize gel products by chemical bonds. The results show that the optimal backfill paste (SFN6) is obtained by one-step mixing technique when SR-FA ratio is 2:3, solution concentration is 2.0 mol/L and liquid-solid ratio is 1.2, in which gel product is the coexistence of calcium silicate hydrated (C–S–H) and Ca-containing geopolymer ((N,C)-A-S-H) according to the detected 2Ca/Al = 1.54 (more than 1.0) and Si/Al = 1.69 (more than 1.0). The results can make extensive utilization of soda residue and low-calcium fly ash in cemented paste backfill to promote cleaner production.
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- 2020
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20. Effect of Soda Residue Addition and Its Chemical Composition on Physical Properties and Hydration Products of Soda Residue-Activated Slag Cementitious Materials
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Xianhui Zhao, Dongqiang Xu, and Yonghui Lin
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microstructure ,0211 other engineering and technologies ,Alkalinity ,02 engineering and technology ,lcsh:Technology ,Article ,physical properties ,chemistry.chemical_compound ,Ammonia ,alkaline activation ,021105 building & construction ,General Materials Science ,Calcium silicate hydrate ,lcsh:Microscopy ,Chemical composition ,lcsh:QC120-168.85 ,lcsh:QH201-278.5 ,lcsh:T ,ground granulated blast furnace slag ,021001 nanoscience & nanotechnology ,Alkali metal ,Compressive strength ,chemistry ,lcsh:TA1-2040 ,Ground granulated blast-furnace slag ,hydration products ,lcsh:Descriptive and experimental mechanics ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,Cementitious ,lcsh:Engineering (General). Civil engineering (General) ,0210 nano-technology ,lcsh:TK1-9971 ,soda residue ,Nuclear chemistry - Abstract
Soda residue (SR), the solid waste of Na2CO3 produced by ammonia soda process, pollutes water and soil, increasing environmental pressure. SR has high alkalinity, and its main components are Ca(OH)2, NaCl, CaCl2, CaSO4, and CaCO3, which accords with the requirements of being an alkali activator. The aim of this research is to investigate the best proportion of SR addition and the contribution of individual chemical components in SR to SR- activated ground granulated blast furnace slag (GGBS) cementitious materials. In this paper, GGBS pastes activated by SR, Ca(OH)2, Ca(OH)2 + NaCl, Ca(OH)2 + CaCl2, Ca(OH)2 + CaSO4, and Ca(OH)2 + CaCO3 were studied regarding setting time, compressive strength (1 d, 3 d, 7 d, 14 d, 28 d), hydration products, and microstructure. The results demonstrate that SR (24%)-activated GGBS pastes possess acceptable setting time and compressive strength (29.6 MPa, 28 d), and its hydration products are calcium silicate hydrate (CSH) gel, calcium aluminum silicate hydrates (CASH) gel and Friedel&rsquo, s salt. CaCl2 in SR plays a main role in hydration products generation and high compressive strength of SR- activated GGBS pastes.
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- 2020
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21. Catalytic cracking of inedible camelina oils to hydrocarbon fuels over bifunctional Zn/ZSM-5 catalysts
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Lin Wei, James Julson, Zhengrong Gu, Yuhe Cao, and Xianhui Zhao
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inorganic chemicals ,chemistry.chemical_classification ,biology ,Chemistry ,General Chemical Engineering ,Inorganic chemistry ,General Chemistry ,biology.organism_classification ,Fluid catalytic cracking ,Camelina ,Catalysis ,Bifunctional catalyst ,chemistry.chemical_compound ,Hydrocarbon ,Adsorption ,ZSM-5 ,Bifunctional ,Nuclear chemistry - Abstract
Catalytic cracking of camelina oils to hydrocarbon fuels over ZSM-5 and ZSM-5 impregnated with Zn2+ (named bifunctional catalyst) was individually carried out at 500 °C using a tubular fixed-bed reactor. Fresh and used catalysts were characterized by ammonia temperature-programmed desorption (NH3-TPD), X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and nitrogen isothermal adsorption/desorption micropore analyzer. The effect of catalysts on the yield rate and qualities of products was discussed. The loading of Zn2+ to ZSM-5 provided additional acid sites and increased the ratio of Lewis acid site to Bronsted acid site. BET results revealed that the surface area and pore volume of the catalyst decreased after ZSM-5 was impregnated with zinc, while the pore size increased. When using the bifunctional catalyst, the pH value and heating value of upgraded camelina oils increased, while the oxygen content and moisture content decreased. Additionally, the yield rate of hydrocarbon fuels increased, while the density and oxygen content decreased. Because of a high content of fatty acids, the distillation residues of cracking oils might be recycled to the process to improve the hydrocarbon fuel yield rate.
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- 2015
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22. Directly catalytic upgrading bio-oil vapor produced by prairie cordgrass pyrolysis over Ni/HZSM-5 using a two stage reactor
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Yinbin Huang, Shouyun Cheng, Changling Qiu, Xianhui Zhao, Douglas E. Raynie, Yong Yu, John Kiratu, and Lin Wei
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prairie cordgrass ,chemistry.chemical_classification ,Materials science ,Renewable Energy, Sustainability and the Environment ,Inorganic chemistry ,Energy Engineering and Power Technology ,Biomass ,pyrolysis ,Fluid catalytic cracking ,Product distribution ,Catalysis ,lcsh:Production of electric energy or power. Powerplants. Central stations ,chemistry.chemical_compound ,hydrocarbon ,Fuel Technology ,Hydrocarbon ,chemistry ,Biofuel ,lcsh:TK1001-1841 ,biofuel ,Ni/HZSM-5 ,Phenols ,Pyrolysis ,Nuclear chemistry - Abstract
Catalytic cracking is one of the most promising processes for thermochemical conversion of biomass to advanced biofuels in recent years. However, current effectiveness of catalysts and conversion efficiency still remain challenges. An investigation of directly catalytic upgrading bio-oil vapors produced in prairie cordgrass (PCG) pyrolysis over Ni/HZSM-5 and HZSM-5 in a two stage packed-bed reactor was carried out. The Ni/HZSM-5 catalyst was synthesized using an impregnation method. Fresh and used catalysts were characterized by BET and XRD. The effects of catalysts on pyrolysis products yields and quality were examined. Both catalysts improved bio-oil product distribution compared to non-catalytic treatment. When PCG pyrolysis vapor was treated with absence of catalyst, the produced bio-oils contained higher alcohols (10.97%) and furans (10.14%). In contrast, the bio-oils contained the second highest hydrocarbons (34.97%)and the highest phenols (46.97%) when PCG pyrolysis vapor was treated with Ni/HZSM-5. Bio-oils containing less ketones and aldehydes were produced by both Ni/HZSM-5 and HZSM-5, but no ketones were found in Ni/HZSM-5 treatment compared to HZSM-5 (2.94%). The pyrolysis gas compositions were also affected by the presenting of HZSM-5 or Ni/HZSM-5 during the catalytic upgrading process. However, higher heating values and elemental compositions (C, H and N) of bio-chars produced in all treatments had no significant difference.
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- 2015
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23. Preparation and properties of bio-geopolymer composites with waste cotton stalk materials
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Li Wang, Zhou Boyu, Guowei Ma, Xin Zhao, and Xianhui Zhao
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Materials science ,Renewable Energy, Sustainability and the Environment ,Scanning electron microscope ,020209 energy ,Strategy and Management ,05 social sciences ,Hydrochloric acid ,02 engineering and technology ,Industrial and Manufacturing Engineering ,Geopolymer ,chemistry.chemical_compound ,Compressive strength ,Flexural strength ,chemistry ,Stalk ,050501 criminology ,0202 electrical engineering, electronic engineering, information engineering ,Fourier transform infrared spectroscopy ,Composite material ,Curing (chemistry) ,0505 law ,General Environmental Science - Abstract
To promote the effective utilization of plant stalk resources, cotton fibers and cotton powders were obtained by crushing and screening waste cotton stalks, which were then utilized for the preparation of bio-geopolymers. This study explores the influence of the size and content of cotton stalk fibers and curing methods based on the physical and mechanical properties of a geopolymer. Pretreatment of cotton stalk was applied to improve the fiber-matrix bonding performance and enhance the mechanical properties of the proposed geopolymers. Compressive and flexural bending tests and a hydrochloric acid erosion test were carried out to measure and evaluate the bio-geopolymers containing cotton stalk powder. Scanning electron microscopy and X-ray energy spectrometer (SEM-EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) techniques were applied to investigate the micro-characteristics of the geopolymerization products. The test results demonstrate that the addition of untreated cotton stalk fibers reduces the density of the geopolymers and the compressive strength, whereas the flexural strength is slightly increased. Alkali treatment has proven to be effective in fiber-matrix bonding, and the compressive and flexural strengths are improved by 4.8% and 11.5% respectively compared to the untreated ones. The cotton stalk powder can effectively improve the compressive strength of geopolymer, while the acid corrosion resistance of bio-geopolymer decreases. Through SEM-EDS, XRD, and FTIR analyses, the effects of cotton stalk powders on geopolymer are mainly filling and cementing. The sugar precipitated from cotton stalk in alkaline environment reduces the compactness of a geopolymer gel. Alkali treatment and PVA solution treatment on cotton stalk can effectively reduce the effect of the precipitated sugar on geopolymer gel.
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- 2020
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24. Enhanced conversion efficiency of dye-sensitized titanium dioxide solar cells by Ca-doping
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Yang Zhou, Yandong Duan, Xianhui Zhao, Yuan Lin, Min Wang, and Qiuping Liu
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Photocurrent ,Electron density ,Materials science ,Mechanical Engineering ,Doping ,Energy conversion efficiency ,Metals and Alloys ,Analytical chemistry ,Dye-sensitized solar cell ,chemistry.chemical_compound ,chemistry ,Mechanics of Materials ,Titanium dioxide ,Materials Chemistry ,Thin film ,HOMO/LUMO - Abstract
Ca salts [CaSO4]-doped TiO2 electrodes prepared with well-optimized condition by the hydrothermal method show an increase in short-circuit (JSC), resulting in a power conversion efficiency (PCE) of 8.35%, which is higher than that of the undoped TiO2 thin film (7.33%). The doping of Ca shifts the flat band potential of TiO2 photoanode positively and increases the electron density indicated by the Mott–Schottky plot. The driving force of injecting electrons from the LUMO of the dye to the conduct band of TiO2 improves apparently because of the positive shift of the flat band potential. The intensity-modulated photocurrent spectroscopy measurement confirms that increased electron density accelerates the electrons transfer rate in the Ca-doped TiO2 thin films by comparison to undoped films.
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- 2013
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25. Study on the Preparation and Properties of Colored Iron Oxide Thin Films
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Su Liu, Chang-hong Li, Song Liang, Xianhui Zhao, Qiuping Liu, Yandong Duan, Hai Wang, and Junjing He
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History ,Materials science ,Scanning electron microscope ,Iron oxide ,Mineralogy ,engineering.material ,Computer Science Applications ,Education ,Tetraethyl orthosilicate ,Absorbance ,chemistry.chemical_compound ,Carbon film ,Coating ,chemistry ,Chemical engineering ,engineering ,Thin film ,Sol-gel - Abstract
Colored iron oxide thin films were prepared using Sol-gel technique. The raw materials were tetraethyl orthosilicate (TEOS), etoh ehanol (EtOH), iron nitrate, and de-ionized water. Various properties were measured and analysed, including the colour of thin films, surface topography, UV-Visible spectra, corrosion resistance and hydrophobicity. To understand how these properties influenced the structural and optical properties of Fe2O3 thin films, Scanning Electron Microscope (SEM), UV Spectrophotometer and other facilities were employed. Many parameters influence the performance of thin films, such as film layers, added H2O content, and the amount of polydimethylsiloxane (PDMS). When the volume ratio of TEOS, EtOH and H2O was 15: 13: 1, the quality of Fe(NO3)3·9H2O was 6g, and pH value was 3, reddish and uniform Fe2O3 thin films with excellent properties were produced. Obtained thin films possessed corrosion resistance in hydrochloric acid with pH=l and the absorption edge wavelength was ~350.2nm. Different H2O contents could result in different morphologies of Fe2O3 nanoparticles. When 1.5 ml PDMS was added into the Sol, thin films possessed hydrophobiliry without dropping. Coating with different layers, thin films appeared different morphologies. Meanwhile, with the increment of film layers, the absorbance increased gradually.
- Published
- 2013
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Catalog
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