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1.
Cureus ; 14(3): e22765, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35371857

ABSTRACT

Primary pleural lymphoma is a rare type of lymphoma that accounts for only ​​0.3% of all non-Hodgkin's lymphomas. The rarity and nonspecific clinical presentation of primary pleural lymphomas pose a diagnostic challenge for clinicians. We present an atypical case of primary pleural lymphoma in an elderly patient without any associated pleuro-pulmonary disease, immunosuppression, or history of lymphoma. To our knowledge, this is one of the first described cases of a primary pleural lymphoma with such a presentation.

2.
ACS Nano ; 9(5): 4698-705, 2015 May 26.
Article in English | MEDLINE | ID: mdl-25858296

ABSTRACT

We describe the synthesis and characterization of monolithic, ultralow density WS2 and MoS2 aerogels, as well as a high surface area MoS2/graphene hybrid aerogel. The monolithic WS2 and MoS2 aerogels are prepared via thermal decomposition of freeze-dried ammonium thio-molybdate (ATM) and ammonium thio-tungstate (ATT) solutions, respectively. The densities of the pure dichalcogenide aerogels represent 0.4% and 0.5% of full density MoS2 and WS2, respectively, and can be tailored by simply changing the initial ATM or ATT concentrations. Similar processing in the presence of the graphene aerogel results in a hybrid structure with MoS2 sheets conformally coating the graphene scaffold. This layered motif produces a ∼50 wt % MoS2 aerogel with BET surface area of ∼700 m(2)/g and an electrical conductivity of 112 S/m. The MoS2/graphene aerogel shows promising results as a hydrogen evolution reaction catalyst with low onset potential (∼100 mV) and high current density (100 mA/cm(2) at 260 mV).

3.
Adv Mater ; 27(9): 1512-8, 2015 Mar 04.
Article in English | MEDLINE | ID: mdl-25503328

ABSTRACT

The dynamic physiochemical response of a functioning graphene-based aerogel supercapacitor is monitored in operando by soft X-ray spectroscopy and interpreted through ab initio atomistic simulations. Unanticipated changes in the electronic structure of the electrode as a function of applied voltage bias indicate structural modifications across multiple length scales via independent pseudocapacitive and electric double layer charge storage channels.

4.
Chem Commun (Camb) ; 48(67): 8428-30, 2012 Aug 28.
Article in English | MEDLINE | ID: mdl-22797515

ABSTRACT

We report the synthesis of a three-dimensional (3D) macroassembly of graphene sheets with electrical conductivity (∼10(2) S m(-1)) and Young's modulus (∼50 MPa) orders of magnitude higher than those previously reported, super-compressive deformation behavior (∼60% failure strain), and surface areas (>1300 m(2) g(-1)) approaching theoretically maximum values.

5.
Appl Microbiol Biotechnol ; 89(6): 2053-63, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21305277

ABSTRACT

A pilot-scale (1,000 L) continuous flow microbial electrolysis cell was constructed and tested for current generation and COD removal with winery wastewater. The reactor contained 144 electrode pairs in 24 modules. Enrichment of an exoelectrogenic biofilm required ~60 days, which is longer than typically needed for laboratory reactors. Current generation was enhanced by ensuring adequate organic volatile fatty acid content (VFA/SCOD ≥ 0.5) and by raising the wastewater temperature (31 ± 1°C). Once enriched, SCOD removal (62 ± 20%) was consistent at a hydraulic retention time of 1 day (applied voltage of 0.9 V). Current generation reached a maximum of 7.4 A/m(3) by the planned end of the test (after 100 days). Gas production reached a maximum of 0.19 ± 0.04 L/L/day, although most of the product gas was converted to methane (86 ± 6%). In order to increase hydrogen recovery in future tests, better methods will be needed to isolate hydrogen gas produced at the cathode. These results show that inoculation and enrichment procedures are critical to the initial success of larger-scale systems. Acetate amendments, warmer temperatures, and pH control during startup were found to be critical for proper enrichment of exoelectrogenic biofilms and improved reactor performance.


Subject(s)
Bioelectric Energy Sources/microbiology , Electricity , Electrolysis , Industrial Microbiology , Water Microbiology , Biofilms/growth & development , Hydrogen/metabolism , Methane/metabolism , Time Factors , Wine/microbiology
6.
Environ Sci Technol ; 43(17): 6870-4, 2009 Sep 01.
Article in English | MEDLINE | ID: mdl-19764262

ABSTRACT

Flat electrodes are useful in microbial fuel cells (MFCs) as close electrode spacing improves power generation. Carbon cloth and carbon paper materials typically used in hydrogen fuel cells, however, are prohibitively expensive for use in MFCs. An inexpensive carbon mesh material was examined here as a substantially less expensive alternative to these materials for the anode in an MFC. Pretreatment of the carbon mesh was needed to ensure adequate MFC performance. Heating the carbon mesh in a muffle furnace (450 degrees C for 30 min) resulted in a maximum power density of 922 mW/m2 (46 W/m3) with this heat-treated anode, which was 3% more power than that produced using a mesh anode cleaned with acetone (893 mW/ m2; 45 W/m3). This power density with heating was only 7% less than that achieved with carbon cloth treated by a high temperature ammonia gas process (988 mW/m2; 49 W/m3). When the carbon mesh was treated by the ammonia gas process, power increased to 1015 mW/m2(51 W/m3). Analysis of the cleaned or heated surfaces showed these processes decreased atomic O/C ratio, indicating removal of contaminants that interfered with charge transfer. Ammonia gas treatment also increased the atomic N/C ratio, suggesting that this process produced nitrogen related functional groups that facilitated electron transfer. These results show that low cost heat-treated carbon mesh materials can be used as the anode in an MFC, providing good performance and even exceeding performance of carbon cloth anodes.


Subject(s)
Bioelectric Energy Sources , Carbon/chemistry , Ammonia/chemistry , Electrochemistry , Electrodes , Hot Temperature , Porosity , Sewage/microbiology
7.
Environ Sci Technol ; 43(6): 2179-83, 2009 Mar 15.
Article in English | MEDLINE | ID: mdl-19368232

ABSTRACT

Microbial electrolysis cells (MECs) are an efficient technology for generating hydrogen gas from organic matter, but alternatives to precious metals are needed for cathode catalysts. We show here that high surface area stainless steel brush cathodes produce hydrogen at rates and efficiencies similar to those achieved with platinum-catalyzed carbon cloth cathodes in single-chamber MECs. Using a stainless steel brush cathode with a specific surface area of 810 m2/m3, hydrogen was produced at a rate of 1.7 +/- 0.1 m3-H2/m3-d (current density of 188 +/- 10 A/m3) at an applied voltage of 0.6 V. The energy efficiency relative to the electrical energy input was 221 +/- 8%, and the overall energy efficiency was 78 +/- 5% based on both electrical energy and substrate utilization. These values compare well to previous results obtained using platinum on flat carbon cathodes in a similar system. Reducing the cathode surface area by 75% decreased performance from 91 +/- 3 A/m3 to 78 +/- 4 A/m3. A brush cathode with graphite instead of stainless steel and a specific surface area of 4600 m2/m3 generated substantially less current (1.7 +/- 0.0 A/m3), and a flat stainless steel cathode (25 m2/m3) produced 64 +/- 1 A/m3, demonstrating that both the stainless steel and the large surface area contributed to high current densities. Linear sweep voltammetry showed that the stainless steel brush cathodes both reduced the overpotential needed for hydrogen evolution and exhibited a decrease in overpotential over time as a result of activation. These results demonstrate for the first time that hydrogen production can be achieved at rates comparable to those with precious metal catalysts in MECs without the need for expensive cathodes.


Subject(s)
Bioelectric Energy Sources , Electrodes , Electrolysis/instrumentation , Stainless Steel , Bacteria/metabolism , Electrolysis/methods , Hydrogen/metabolism , Platinum
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