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1.
Zhongguo Zhen Jiu ; 44(3): 266-270, 2024 Mar 12.
Article in English, Chinese | MEDLINE | ID: mdl-38467500

ABSTRACT

OBJECTIVES: To observe the clinical efficacy of opening-closing six-qi acupuncture combined with western medication for primary hypertension of liver yang hyperactivity, and explore its action mechanism. METHODS: A total of 96 patients with primary hypertension of liver yang hyperactivity were randomly divided into an acupuncture group (48 cases) and a western medication group (48 cases, 2 cases eliminated, 1 case discontinued). The western medication group was given felodipine sustained-release tablets orally, 5 mg each time, once a day. The acupuncture group was treated with opening-closing six-qi acupuncture at tender points of shaoyang and yangming areas of the head on the basis of the western medication group, once every other day. A total of 4 weeks were required in both groups. The blood pressure before treatment and after 2, 4 weeks of treatment, the TCM syndrome score and serum levels of hypersensitive C-reactive protein (hs-CRP), interleukin-6 (IL-6), homocysteine (Hcy) before and after treatment were observed, and the clinical efficacy was evaluated in the two groups. RESULTS: After 2, 4 weeks of treatment, the systolic blood pressure(SBP)and diastolic blood pressure(DBP) in both groups were decreased compared with those before treatment(P<0.05);except for DBP after 2 weeks of treatment, the SBP and DBP in the acupuncture group were lower than those in the western medication group(P<0.05). After treatment, the TCM syndrome scores and serum levels of hs-CRP, IL-6, Hcy were decreased compared with those before treatment in the two groups(P<0.05), those in the acupuncture group were lower than those in the western medication group(P<0.05).The total effective rate of the acupuncture group was 95.8% (46/48), which was higher than 73.3% (33/45) in the western medication group(P<0.05). CONCLUSIONS: Opening-closing six-qi acupuncture combined with western medication could lower blood pressure, improve symptoms in patients with primary hypertension of liver yang hyperactivity.Its mechanism may be related to down-regulation of inflammatory factors.


Subject(s)
Acupuncture Therapy , Qi , Humans , C-Reactive Protein , Interleukin-6 , Acupuncture Points , Liver , Treatment Outcome , Essential Hypertension/drug therapy
2.
Materials (Basel) ; 17(5)2024 Feb 26.
Article in English | MEDLINE | ID: mdl-38473546

ABSTRACT

Recently, the manufacturing of porous polydimethylsiloxane (PDMS) with engineered porosity has gained considerable interest due to its tunable material properties and diverse applications. An innovative approach to control the porosity of PDMS is to use transient liquid phase water to improve its mechanical properties, which has been explored in this work. Adjusting the ratios of deionized water to the PDMS precursor during blending and subsequent curing processes allows for controlled porosity, yielding water emulsion foam with tailored properties. The PDMS-to-water weight ratios were engineered ranging from 100:0 to 10:90, with the 65:35 specimen exhibiting the best mechanical properties with a Young's Modulus of 1.17 MPa, energy absorption of 0.33 MPa, and compressive strength of 3.50 MPa. This led to a porous sample exhibiting a 31.46% increase in the modulus of elasticity over a bulk PDMS sample. Dowsil SE 1700 was then added, improving the storage capabilities of the precursor. The optimal storage temperature was probed, with -60 °C resulting in great pore stability throughout a three-week duration. The possibility of using these water emulsion foams for paste extrusion additive manufacturing (AM) was also analyzed by implementing a rheological modifier, fumed silica. Fumed silica's impact on viscosity was examined, revealing that 9 wt% of silica demonstrates optimal rheological behaviors for AM, bearing a viscosity of 10,290 Pa·s while demonstrating shear-thinning and thixotropic behavior. This study suggests that water can be used as pore-formers for PDMS in conjunction with AM to produce engineered materials and structures for aerospace, medical, and defense industries as sensors, microfluidic devices, and lightweight structures.

3.
Nanomaterials (Basel) ; 13(24)2023 Dec 15.
Article in English | MEDLINE | ID: mdl-38133045

ABSTRACT

The integration of 3D printed sensors into hosting structures has become a growing area of research due to simplified assembly procedures, reduced system complexity, and lower fabrication cost. Embedding 3D printed sensors into structures or bonding the sensors on surfaces are the two techniques for the integration of sensors. This review extensively discusses the fabrication of sensors through different additive manufacturing techniques. Various additive manufacturing techniques dedicated to manufacture sensors as well as their integration techniques during the manufacturing process will be discussed. This review will also discuss the basic sensing mechanisms of integrated sensors and their applications. It has been proven that integrating 3D printed sensors into infrastructures can open new possibilities for research and development in additive manufacturing and sensor materials for smart goods and the Internet of Things.

4.
Biochem Biophys Res Commun ; 679: 191-204, 2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37703762

ABSTRACT

BACKGROUND: FHIP1A-DT is a long non-coding RNA (lncRNA) obtained by divergent transcription whose mechanism in pan-cancer and colorectal cancer (CRC) is unclear. We elucidated the molecular mechanism of FHIP1A-DT through bioinformatics analysis and in vitro experiments. METHODS: Pan-cancer and CRC data were downloaded from the University of California, Santa Cruz (UCSC) Genome Browser and the Cancer Genome Atlas (TCGA). We analyzed FHIP1A-DT expression and its relationship with clinical stage, diagnosis, prognosis, and immunity characteristics in pan-cancer. We also analyzed FHIP1A-DT expression in CRC and explored the relationship between FHIP1A-DT and CRC diagnosis and prognosis. Then, we analyzed the correlation between FHIP1A-DT and drug sensitivity, immune cell infiltration, and the biological processes involved in FHIP1A-DT. The competing endogenous RNA (ceRNA) regulatory network associated with FHIP1A-DT was explored. External validation was conducted using external data sets GSE17538 and GSE39582 and in vitro experiments. RESULTS: FHIP1A-DT expression was different in pan-cancer and had excellent diagnostic and prognostic capability for pan-cancer. FHIP1A-DT was also related to the pan-cancer tumor mutation burden (TMB), microsatellite instability (MSI), and immune cell content. FHIP1A-DT was downregulated in CRC, where patients with CRC with low FHIP1A-DT expression had a worse prognosis. A nomogram combined with FHIP1A-DT expression demonstrated excellent predictive ability for prognosis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated that FHIP1A-DT was associated with epigenetic modification and regulated many cancer-related pathways. The ceRNA network demonstrated the potential gene regulation of FHIP1A-DT. FHIP1A-DT was related to many chemotherapeutic drug sensitivities and immune cell infiltration such as CD4 memory resting T cells, monocytes, plasma cells, neutrophils, and M2 macrophages. The FHIP1A-DT expression and prognostic analysis of GSE17538 and GSE39582, and qPCR yielded similar external verification results. CONCLUSION: FHIP1A-DT was a novel CRC-related lncRNA related to CRC diagnosis, prognosis, and treatment sensitivity. It could be used as a significant CRC biomarker in the future.

5.
Curr Issues Mol Biol ; 45(7): 5515-5533, 2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37504265

ABSTRACT

Digestive system cancer and COVID-19 significantly affect the digestive system, but the mechanism of interaction between COVID-19 and the digestive system cancers has not been fully elucidated. We downloaded the gene expression of COVID-19 and seven digestive system cancers (oral, esophageal, gastric, colorectal, hepatocellular, bile duct, pancreatic) from GEO and identified hub differentially expressed genes. Multiple verifications, diagnostic efficacy, prognostic analysis, functional enrichment and related transcription factors of hub genes were explored. We identified 23 common DEGs for subsequent analysis. CytoHubba identified nine hub genes (CCNA2, CCNB1, CDKN3, ECT2, KIF14, KIF20A, KIF4A, NEK2, TTK). TCGA and GEO data validated the expression and excellent diagnostic and prognostic ability of hub genes. Functional analysis revealed that the processes of cell division and the cell cycle were essential in COVID-19 and digestive system cancers. Furthermore, six related transcription factors (E2F1, E2F3, E2F4, MYC, TP53, YBX1) were involved in hub gene regulation. Via in vitro experiments, CCNA2, CCNB1, and MYC expression was verified in 25 colorectal cancer tissue pairs. Our study revealed the key biomarks and common pathogenesis of digestive system cancers and COVID-19. These may provide new ideas for further mechanistic research.

6.
BMC Bioinformatics ; 24(1): 103, 2023 Mar 20.
Article in English | MEDLINE | ID: mdl-36941538

ABSTRACT

BACKGROUND: Colon cancer (CC) is a common tumor that causes significant harm to human health. Bacteria play a vital role in cancer biology, particularly the biology of CC. Genes related to bacterial response were seldom used to construct prognosis models. We constructed a bacterial response-related risk model based on three Molecular Signatures Database gene sets to explore new markers for predicting CC prognosis. METHODS: The Cancer Genome Atlas (TCGA) colon adenocarcinoma samples were used as the training set, and Gene Expression Omnibus (GEO) databases were used as the test set. Differentially expressed bacterial response-related genes were identified for prognostic gene selection. Univariate Cox regression analysis, least absolute shrinkage and selection operator-penalized Cox regression analysis, and multivariate Cox regression analysis were performed to construct a prognostic risk model. The individual diagnostic effects of genes in the prognostic model were also evaluated. Moreover, differentially expressed long noncoding RNAs (lncRNAs) were identified. Finally, the expression of these genes was validated using quantitative polymerase chain reaction (qPCR) in cell lines and tissues. RESULTS: A prognostic signature was constructed based on seven bacterial response genes: LGALS4, RORC, DDIT3, NSUN5, RBCK1, RGL2, and SERPINE1. Patients were assigned a risk score based on the prognostic model, and patients in the TCGA cohort with a high risk score had a poorer prognosis than those with a low risk score; a similar finding was observed in the GEO cohort. These seven prognostic model genes were also independent diagnostic factors. Finally, qPCR validated the differential expression of the seven model genes and two coexpressed lncRNAs (C6orf223 and SLC12A9-AS1) in 27 pairs of CC and normal tissues. Differential expression of LGALS4 and NSUN5 was also verified in cell lines (FHC, COLO320DM, SW480). CONCLUSIONS: We created a seven-gene bacterial response-related gene signature that can accurately predict the outcomes of patients with CC. This model can provide valuable insights for personalized treatment.


Subject(s)
Adenocarcinoma , Colonic Neoplasms , RNA, Long Noncoding , Humans , Colonic Neoplasms/genetics , Galectin 4 , Biomarkers , Biomarkers, Tumor/genetics
7.
Sensors (Basel) ; 23(6)2023 Mar 22.
Article in English | MEDLINE | ID: mdl-36992062

ABSTRACT

This research presents a simple method to additively manufacture Cone 5 porcelain clay ceramics by using the direct ink-write (DIW) printing technique. DIW has allowed the application of extruding highly viscous ceramic materials with relatively high-quality and good mechanical properties, which additionally allows a freedom of design and the capability of manufacturing complex geometrical shapes. Clay particles were mixed with deionized (DI) water at different ratios, where the most suitable composition for 3D printing was observed at a 1:5 w/c ratio (16.2 wt.%. of DI water). Differential geometrical designs were printed to demonstrate the printing capabilities of the paste. In addition, a clay structure was fabricated with an embedded wireless temperature and relative humidity (RH) sensor during the 3D printing process. The embedded sensor read up to 65% RH and temperatures of up to 85 °F from a maximum distance of 141.7 m. The structural integrity of the selected 3D printed geometries was confirmed through the compressive strength of fired and non-fired clay samples, with strengths of 70 MPa and 90 MPa, respectively. This research demonstrates the feasibility of using the DIW printing of porcelain clay with embedded sensors, with fully functional temperature- and humidity-sensing capabilities.

8.
Materials (Basel) ; 14(16)2021 Aug 12.
Article in English | MEDLINE | ID: mdl-34443043

ABSTRACT

The growing demand for wearable devices, soft robotics, and tissue engineering in recent years has led to an increased effort in the field of soft materials. With the advent of personalized devices, the one-shape-fits-all manufacturing methods may soon no longer be the standard for the rapidly increasing market of soft devices. Recent findings have pushed technology and materials in the area of additive manufacturing (AM) as an alternative fabrication method for soft functional devices, taking geometrical designs and functionality to greater heights. For this reason, this review aims to highlights recent development and advances in AM processable soft materials with self-healing, shape memory, electronic, chromic or any combination of these functional properties. Furthermore, the influence of AM on the mechanical and physical properties on the functionality of these materials is expanded upon. Additionally, advances in soft devices in the fields of soft robotics, biomaterials, sensors, energy harvesters, and optoelectronics are discussed. Lastly, current challenges in AM for soft functional materials and future trends are discussed.

9.
Sci Total Environ ; 704: 135406, 2020 Feb 20.
Article in English | MEDLINE | ID: mdl-31896226

ABSTRACT

While the use of TiO2 nanoparticles in the form of slurry/suspension requires energy-intensive separation processes, its immobilization in solid support may open new opportunities in the area of sustainable water treatment technologies. In this study, a novel method for the development of photocatalytic paint based on TiO2 nanoparticles and acrylate-based photopolymer resin is reported. The paint (TiO2@polymer) was applied on substrates such as plastic petri dish and glass jar, which was polymerized/solidified by ultraviolet light irradiation. The painted petri dish and glass jar were used for the photocatalytic degradation of model organic pollutants viz. methyl orange (MO), methylene blue (MB), and indole in deionized water, simulated fresh drinking water, and tap water matrices. The photocatalytic degradation studies were performed under sunlight and UV-B light were used for. The sunlight-assisted photocatalytic degradation of MO and MB was found to be faster and more efficient than the UV-B light-assisted ones. Under UV-B light irradiation, it took 120 min to degrade about 80% of 6 ppm MB solution, whereas under sunlight irradiation it took 60 min to degrade about 90% of the same MB solution. The photocatalytic paint generated hydroxyl radical (·OH) under the UV-B and sunlight irradiation, which was studied by the terephthalic acid fluorescence tests. Further, the potential release of TiO2 during the exposure to UV irradiation was studied by single particle ICP-MS analysis.

10.
BMC Complement Altern Med ; 18(1): 313, 2018 Nov 29.
Article in English | MEDLINE | ID: mdl-30497462

ABSTRACT

BACKGROUND: Tuberculosis (TB) is one of the world's major communicable infectious diseases, and it still imposes a great health burden in developing countries. The development of drug-resistant TB during the treatment increases the treatment complexity, and the long-term pulmonary complications after completing treatment raise the epidemic health burden. This study intended to investigate the utilization of Chinese medicine (CM) for respiratory symptoms by patients with a medical history of TB in Taiwan. METHODS: We analyzed a cohort of one million individuals who were randomly selected from the National Health Insurance Research Database in Taiwan. The inclusion criteria of patients (n = 7905) with history of TB (ICD-9-CM codes 010-018 and A02) were: (1) TB diagnosed between January 1, 1997 and December 31, 2010 (2) 18 years old or over (3) Clinical records for at least 2 months with complete demographic information (4) Record of treatment with first-line TB medication prescriptions. CM users for conditions other than respiratory discomforts (n = 3980) were excluded. Finally, a total of 3925 TB patients were categorized as: CM users for respiratory discomforts (n = 2051) and non-CM users (n = 1874). RESULTS: Among the 3925 subjects, 2051 (52.25%) were CM users, and 1874 (44.753%) were non-CM users. Female patients and those who were younger (18-39 y/o) and who lived in urbanized areas relatively tended to be CM users (p < .0001). Most of the CM users (1944, 94.78%) received Chinese medicines. The most commonly prescribed herbal formulas and single herbs were Xiao-Qing-Long-Tang and Radix Platycodonis (Jie-Geng), respectively. The core pattern of Chinese medicines for TB patients consisted of Ma-Xing-Gan-Shi-Tang, Bulbus Fritillariae Thunbergii (Bei-Mu), Radix Platycodonis (Jie-Geng) and Semen Armeniacae (Xing-Ren). CONCLUSIONS: The use of CM is popular among patients with a medical history of TB complicated with long-term respiratory discomforts in Taiwan. Further pharmacological investigations and clinical trials are required.


Subject(s)
Drugs, Chinese Herbal/therapeutic use , Respiratory Tract Diseases/drug therapy , Tuberculosis/drug therapy , Adult , Aged , Cohort Studies , Databases, Factual , Humans , Male , Middle Aged , Taiwan
11.
Int J Mol Med ; 42(1): 665-673, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29693153

ABSTRACT

Colorectal cancer (CRC) is one of the major types of cancer and causes of mortality worldwide, and it remains the third most common cause of cancer­associated mortality worldwide. MicroRNAs (miRNAs) are a class of small RNAs, which have been shown to be associated with CRC. In the present study, an MTT assay and proliferating cell nuclear antigen (PCNA) protein examination assay were performed to detect RKO cell viability. Hoechst staining, and caspase­3 activity and BrdU incorporation assays were performed to detect RKO cell apoptosis, respectively. Reverse transcription­quantitative polymerase chain reaction (RT­qPCR) and western blot analyses were used to analyze the expression of cyclooxygenase­2 (COX­2). Western blot analysis was also used to analyze the expression of vascular endothelial growth factor (VEGF) and mitogen­activated protein kinase (MAPK) signal molecules, including extracellular signal­regulated kinase (ERK), p38 and c­Jun N­terminal kinase (JNK). The target genes of miR-125 were predicted using a double luciferase reporter gene assay. The results of the MTT assay showed that RKO cell viability was decreased by an miRNA-125 mimic and increased by the miRNA-125 inhibitor. The RKO cell viability was significantly correlated with the expression of PCNA. The migration of RKO cells was significantly downregulated in the miR-125 mimics­transfected cells and upregulated in the miRNA-125 inhibitor­transfected cells. The results of Hoechst staining and the caspase­3 activity and BrdU incorporation assays showed that RKO cell apoptosis was increased following miRNA-125 mimic transfection and decreased following miRNA-125 inhibitor transfection. The results of the RT­qPCR and western blot analysis showed that the expression of COX­2 was increased in the miR-125 mimic­transfected cells and decreased in the miR-125 inhibitor­transfected cells. Using an online miRNA target prediction database, the double luciferase reporter gene assay showed that miR­125 targeted and inhibited the expression of VEGF through target sites located in the 3' untranslated region of VEGF mRNA. In conclusion, the abnormal expression of miR­125 was found to be closely associated with CRC. Therefore, miR­125 may be a novel therapeutic target for CRC.


Subject(s)
Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , MicroRNAs/metabolism , Vascular Endothelial Growth Factor A/metabolism , 3' Untranslated Regions/genetics , Apoptosis/genetics , Base Sequence , Cell Death , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Cyclooxygenase 2/metabolism , Gene Expression Regulation, Neoplastic , Humans , Luciferases/metabolism , MAP Kinase Signaling System/genetics , MicroRNAs/genetics
12.
ACS Omega ; 3(8): 10243-10249, 2018 Aug 31.
Article in English | MEDLINE | ID: mdl-31459153

ABSTRACT

Our work reports the hydrothermal synthesis of a bimetallic composite CoMoS, followed by the addition of cellulose fibers and its subsequent carbonization under Ar atmosphere (CoMoS@C). For comparison, CoMoS was heat-treated under the same conditions and referred as bare-CoMoS. X-ray diffraction analysis indicates that CoMoS@C composite matches with the CoMoS4 phase with additional peaks corresponding to MoO3 and CoMoO4 phases, which probably arise from air exposure during the carbonization process. Scanning electron microscopy images of CoMoS@C exhibit how the CoMoS material is anchored to the surface of carbonized cellulose fibers. As anode material, CoMoS@C shows a superior performance than bare-CoMoS. The CoMoS@C composite presents an initial high discharge capacity of ∼1164 mA h/g and retains a high specific discharge capacity of ∼715 mA h/g after 200 cycles at a current density of 500 mA/g compared to that of bare-CoMoS of 102 mA h/g. The high specific capacity and good cycling stability could be attributed to the synergistic effects of CoMoS and carbonized cellulose fibers. The use of biomass in the anode material represents a very easy and cost-effective way to improve the electrochemical Li-ion battery performance.

13.
RSC Adv ; 8(57): 32545-32557, 2018 Sep 18.
Article in English | MEDLINE | ID: mdl-35547662

ABSTRACT

The adsorptive removal of environmental pollutants is an effective method for the treatment of contaminated water. Thus, the preparation of adsorbents from low-cost, readily available, and renewable resources has garnered immense attention in recent years. In this study, a facile one-step method for the preparation of a high-capacity adsorbent is demonstrated by refluxing pine cones in concentrated sulfuric acid. With sulfuric acid reflux, the pine cones undergone carbonization as well as functionalization with sulfonic acid groups. The adsorbent demonstrated high adsorption capacity for two emerging organic pollutants, methylene blue (MB) and tetracycline (TC). Different variables such as pH, temperature, contact time, and initial concentration of the pollutants were analyzed and showed that the adsorption capacity for MB increased in a basic pH and vice versa for TC. Also, the elevated temperature favored the adsorption for both MB and TC. The maximum adsorption capacity was found to be 1666.66, and 357.14 mg g-1 for MB and TC, respectively. In comparison to the pristine pine cone, the sulfuric acid treated pine cone demonstrated an extraordinary improvement in the adsorption capacity. The adsorption of MB and TC was performed from the tap water matrix and similar adsorption capacities were found. A packed glass column was also prepared to demonstrate the adsorption of MB from tap water under flow conditions.

14.
BMC Complement Altern Med ; 17(1): 427, 2017 Aug 29.
Article in English | MEDLINE | ID: mdl-28851349

ABSTRACT

BACKGROUND: Many patients with gynecological disorders seek traditional medicine consultations in Asian countries. This study intended to investigate the utilization of traditional Chinese medicine (TCM) in patients with dysfunctional uterine bleeding (DUB) in Taiwan. METHODS: We analyzed a cohort of one million individuals randomly selected from the National Health Insurance Research Database in Taiwan. We included 46,337 subjects with newly diagnosed DUB (ICD-9-CM codes 626.8) from January 1, 1997 to December 31, 2010. The patients were categorized into TCM seekers and non-TCM seekers according to their use of TCM. RESULTS: Among the subjects, 41,558 (89.69%) were TCM seekers and 4,779 (10.31%) were non-TCM seekers. Patients who were younger tended to be TCM seekers. Most of the patients had also taken Western medicine, especially tranexamic acid and non-steroidal anti-inflammatory drugs (NSAIDs). More than half of TCM seekers (55.41%) received combined treatment with both Chinese herbal remedies and acupuncture. The most commonly used TCM formula and single herb were Jia-Wei-Xiao-Yao-San (Bupleurum and Peony Formula) and Yi-Mu-Cao (Herba Leonuri), respectively. The core pattern of Chinese herbal medicine for DUB patients consisted of Jia-Wei-Xiao-Yao-San, Xiang-Fu (Rhizoma Cyperi), and Yi-Mu-Cao (Herba Leonuri). CONCLUSIONS: TCM use is popular among patients with DUB in Taiwan. Further pharmacological investigations and clinical trials are required to validate the efficacy and safety of these items.


Subject(s)
Medicine, Chinese Traditional/statistics & numerical data , Metrorrhagia/therapy , Acupuncture Therapy , Adolescent , Adult , Cohort Studies , Combined Modality Therapy , Databases, Factual , Drugs, Chinese Herbal/administration & dosage , Female , Health Surveys , Humans , Male , Metrorrhagia/drug therapy , Taiwan , Young Adult
15.
Nanoscale ; 5(22): 10901-7, 2013 Nov 21.
Article in English | MEDLINE | ID: mdl-24056918

ABSTRACT

A novel method for synthesis of Barium Strontium Titanate (BST) films with a high degree of texture is developed with a two-step hydrothermal reaction and without the need for costly equipment. The dielectric constant and ferroelectric properties of the film can be tuned by varying the Ba : Sr molar ratio of the materials. The maximum ambient temperature dielectric constant of these BST films can reach 811 when the Ba molar fraction ("x" in BaxSr1-xTiO3) is 0.71, which corresponds with the tetragonal to cubic phase transition of the solid solution. The ferroelectric behavior of the Ba0.91Sr0.09TiO3 film is confirmed by atomic force microscopy (AFM).

16.
ACS Appl Mater Interfaces ; 5(16): 7881-5, 2013 Aug 28.
Article in English | MEDLINE | ID: mdl-23806171

ABSTRACT

Lithium-ion batteries (LIB) have been receiving extensive attention because of the high specific energy density for wide applications such as electronic vehicles, commercial mobile electronics, and military applications. In LIB, graphite is the most commonly used anode material; however, lithium-ion intercalation in graphite is limited, hindering the battery charge rate and capacity. To overcome this obstacle, nanostructured anode assembly has been extensively studied to increase the lithium-ion diffusion rate. Among these approaches, high specific surface area metal oxide nanowires connecting nanostructured carbon materials accumulation have shown propitious results for enhanced lithium intercalation. Recently, nanowire/graphene hybrids were developed for the enhancement of LIB performance; however, almost all previous efforts employed nanowires on graphene in a random fashion, which limited lithium-ion diffusion rate. Therefore, we demonstrate a new approach by hydrothermally growing uniform nanowires on graphene aerogel to further improve the performance. This nanowire/graphene aerogel hybrid not only uses the high surface area of the graphene aerogel but also increases the specific surface area for electrode-electrolyte interaction. Therefore, this new nanowire/graphene aerogel hybrid anode material could enhance the specific capacity and charge-discharge rate. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used for materials characterization. Battery analyzer and potentio-galvanostat are used for measuring the electrical performance of the battery. The testing results show that nanowire graphene hybrid anode gives significantly improved performance compared to graphene anode.


Subject(s)
Graphite/chemistry , Lithium/chemistry , Oxides/chemistry , Carbon/chemistry , Electric Power Supplies , Electrodes , Nanostructures/chemistry , Nanowires/chemistry , Surface Properties , X-Ray Diffraction
17.
Nanotechnology ; 24(9): 095602, 2013 Mar 08.
Article in English | MEDLINE | ID: mdl-23395987

ABSTRACT

Textured barium titanate (BaTiO(3)) films are attracting immense research interest due to their lead-free composition and excellent piezoelectric and dielectric properties. Most synthesis methods for these films require a high temperature, leading to the formation of a secondary phase and an overall decrease in the electrical properties of the ceramic. In order to alleviate these issues, a novel fabrication method is introduced by transferring oriented rutile TiO(2) nanowires to a textured BaTiO(3) film at temperatures below 160 °C. The microstructure and thickness of the fabricated BaTiO(3) films were characterized by scanning electron microscopy, and the crystal structure and degree of orientation were evaluated by x-ray diffraction patterns using the Lotgering method. It is shown that the thickness of the BaTiO(3) film can be controlled by the length of TiO(2) nanowire array template, and the degree of orientation of the textured BaTiO(3) films is highly dependent on the film thickness; the crystallographic orientation has been measured to reach up to 87%. The relative dielectric constant (ε(r) = 1300) and ferroelectric properties (P(r) = 2.7 µC cm(-2), E(c) = 4.0 kV mm(-1)) of the textured BaTiO(3) films were also characterized to demonstrate their potential application in sensors, random access memory, and micro-electromechanical systems.

18.
Nano Lett ; 12(1): 84-90, 2012 Jan 11.
Article in English | MEDLINE | ID: mdl-22103581

ABSTRACT

Graphene consists of a monolayer of sp(2) bonded carbon atoms and has attracted considerable interest over recent years due to its extreme mechanical, electrical, and thermal properties. Graphene nanocomposites have naturally begun to be studied to capitalize upon these properties. A range of complex chemical and physical processing methods have been devised that achieve isolated graphene sheets that attempt to prevent aggregation. Here we demonstrate that the simple casting of a polymer solution containing dispersed graphene oxide, followed by thermal reduction, can produce well-isolated monolayer reduced-graphene oxide. The presence of single layer reduced-graphene oxide is quantitatively demonstrated through transmission electron microscopy and selected area electron diffraction studies and the reduction is verified by thermogravimetric, X-ray photoelectron spectroscopy, infrared spectrum, and electrical conductivity studies. These findings provide a simple, environmentally benign and commercially viable process to produce reduced-graphene oxide reinforced polymers without complex manufacturing, dispersion or reduction processes.


Subject(s)
Crystallization/methods , Graphite/chemistry , Nanostructures/chemistry , Nanostructures/ultrastructure , Hot Temperature , Macromolecular Substances/chemistry , Materials Testing , Molecular Conformation , Particle Size , Surface Properties
19.
ACS Appl Mater Interfaces ; 3(7): 2200-3, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21714511

ABSTRACT

Carbon-based nanomaterials such as carbon nanotubes and graphene are excellent candidates for superhydrophobic surfaces because of their intrinsically high surface area and nonpolar carbon structure. This paper demonstrates that graphene aerogels with a silane surface modification can provide superhydrophobicity. Graphene aerogels of various concentrations were synthesized and the receding contact angle of a water droplet was measured. It is shown that graphene aerogels are hydrophobic and become superhydrophobic following the application of a fluorinated surfactant. The aerogels produced for this experiment outperform previous carbon nanomaterials in creating superhydrophobic surfaces and offer a more scalable synthetic procedure for production.

20.
Nanotechnology ; 22(1): 015702, 2011 Jan 07.
Article in English | MEDLINE | ID: mdl-21135449

ABSTRACT

High energy storage plays an important role in the modern electric industry. Herein, we investigated the role of filler aspect ratio in nanocomposites for energy storage. Nanocomposites were synthesized using lead zirconate titanate (PZT) with two different aspect ratio (nanowires, nanorods) fillers at various volume fractions dispersed in a polyvinylidene fluoride (PVDF) matrix. The permittivity constants of composites containing nanowires (NWs) were higher than those with nanorods (NRs) at the same inclusion volume fraction. It was also indicated that the high frequency loss tangent of samples with PZT nanowires was smaller than for those with nanorods, demonstrating the high electrical energy storage efficiency of the PZT NW nanocomposite. The high aspect ratio PZT NWs showed a 77.8% increase in energy density over the lower aspect ratio PZT NRs, under an electric field of 15 kV mm(-1) and 50% volume fraction. The breakdown strength was found to decrease with the increasing volume fraction of PZT NWs, but to only change slightly from a volume fraction of around 20%-50%. The maximum calculated energy density of nanocomposites is as high as 1.158 J cm(-3) at 50% PZT NWs in PVDF. Since the breakdown strength is lower compared to a PVDF copolymer such as poly(vinylidene fluoride-tertrifluoroethylene-terchlorotrifluoroethylene) P(VDF-TreEE-CTFE) and poly(vinylidene fluoride-co-hexafluoropropylene) P(VDF-HFP), the energy density of the nanocomposite could be significantly increased through the use of PZT NWs and a polymer with greater breakdown strength. These results indicate that higher aspect ratio fillers show promising potential to improve the energy density of nanocomposites, leading to the development of advanced capacitors with high energy density.

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