A Fuel‐Flexible Alkaline Direct Liquid Fuel Cell

We constructed a fuel‐flexible fuel cell consisting of an alkaline anion exchange membrane, palladium anode, and platinum cathode. When an alcohol fuel was used with potassium hydroxide added to the fuel stream and oxygen was the oxidant, the following maximum power densities were achieved at 60 °C: ethanol (128 mW cm⁻²), 1‐propanol (101 mW cm⁻²), 2‐propanol (40 mW cm⁻²), ethylene glycol (117 mW cm⁻²), glycerol (78 mW cm⁻²), and propylene glycol (75 mW cm⁻²). We also observed a maximum power density of 302 mW cm⁻² when potassium formate was used as the fuel under the same conditions. However, when potassium hydroxide was removed from the fuel stream, the maximum power density with ethanol decreased to 9 mW cm⁻² (using oxygen as oxidant), while with formate it only decreased to 120 mW cm⁻² (using air as the oxidant). Variations in the performance of each fuel are discussed. This fuel‐flexible fuel cell configuration is promising for a number of alcohol fuels. It is especially promising with potassium formate, since it does not require hydroxide added to the fuel stream for efficient operation.     

葡萄酒酿造中乙醛的形成及其重要作用

乙醛是葡萄酒中的一种重要的风味化合物。对乙醛的生化合成进行了综述，并就SO2对乙醛的影响以及乙醛对葡萄酒颜色和物理稳定性的影响进行了概述，最后，对乙醛在葡萄酒酿造实践中的微生物学意义进行重点综述。     

Exposure to particles from laser printers operating within office workplaces

While recent research has provided valuable information as to the composition of laser printer particles, their formation mechanisms, and explained why some printers are emitters while others are low emitters, questions relating to the potential exposure of office workers remained unanswered. In particular, (i) what impact does the operation of laser printers have on the background particle number concentration (PNC) of an office environment over the duration of a typical working day? (ii) What is the airborne particle exposure to office workers in the vicinity of laser printers? (iii) What influence does the office ventilation have upon the transport and concentration of particles? (iv) Is there a need to control the generation of, and/or transport of particles arising from the operation of laser printers within an office environment? (v) What instrumentation and methodology is relevant for characterizing such particles within an office location? We present experimental evidence on printer temporal and spatial PNC during the operation of 107 laser printers within open plan offices of five buildings. The 8 h time-weighted average printer particle exposure is significantly less than the 8 h time-weighted local background particle exposure, but that peak printer particle exposure can be greater than 2 orders of magnitude higher than local background particle exposure. The particle size range is predominantly ultrafine (<100 nm diameter). In addition we have established that office workers are constantly exposed to nonprinter derived particle concentrations, with up to an order of magnitude difference in such exposure among offices, and propose that such exposure be controlled along with exposure to printer derived particles. We also propose, for the first time, that peak particle reference values be calculated for each office area analogous to the criteria used in Australia and elsewhere for evaluating exposure excursion above occupational hazardous chemical exposure standards. A universal peak particle reference value of 2.0 × 10(4) particles cm(-3) has been proposed.     

An optimal loading principle of burnable poisons for an OTTO refueling scheme in pebble bed HTGR cores

An optimal loading principle of burnable poisons (BPs) is proposed to eliminate the problem of an excessively high power peaking factor in once-through-then-out (OTTO) pebble bed HTGR cores. The effectiveness of the principle is confirmed through neutronic and thermal hydraulic calculations for an HTGR core with thermal power of 600 MWt. Spherical BP particles are distributed uniformly together with TRISO-coated fuel particle inside the free fuel zones of fuel pebbles to maintain constant k_∞ during burnup. The applicability of BP materials, such as B₄C, Gd₂O₃, Sm₂O₃, Eu₂O₃, Er₂O₃, CdO, and HfO₂, is investigated. Because complete BP depletion at the target burnup is required to avoid reactivity loss and extra enrichment, the four BP materials considered as applicable candidates are B₄C, Gd₂O₃, Er₂O₃, and CdO. The complete BP depletion is demonstrated by a burning fraction at the target burnup. The power density is excessively high at the core top and the power peaking factor is 4.44 when no BP is added to the fuel pebbles. Optimal BP loading reduces the power peaking factor from 4.44 to about 1.7. Because of the power peaking factor reduction, the maximum fuel temperatures are lower than the maximum permissible values of 1250 °C for normal operation and 1600 °C during a depressurization accident.     

Molecularly Targeted Agents as Radiosensitizers in Cancer Therapy—Focus on Prostate Cancer

As our understanding of the molecular pathways driving tumorigenesis improves and more druggable targets are identified, we have witnessed a concomitant increase in the development and production of novel molecularly targeted agents. Radiotherapy is commonly used in the treatment of various malignancies with a prominent role in the care of prostate cancer patients, and efforts to improve the therapeutic ratio of radiation by technologic and pharmacologic means have led to important advances in cancer care. One promising approach is to combine molecularly targeted systemic agents with radiotherapy to improve tumor response rates and likelihood of durable control. This review first explores the limitations of preclinical studies as well as barriers to successful implementation of clinical trials with radiosensitizers. Special considerations related to and recommendations for the design of preclinical studies and clinical trials involving molecularly targeted agents combined with radiotherapy are provided. We then apply these concepts by reviewing a representative set of targeted therapies that show promise as radiosensitizers in the treatment of prostate cancer.     

Lidocaine-loaded biodegradable nanospheres. I. Optimization Of the drug incorporation into the polymer matrix

Spherical nanoparticulate drug carriers made of poly(d,l-lactic acid) with controlled size were designed. A local anesthetic, lidocaine, a small hydrophobic molecule, was incorporated in the core with loadings varying from about 7 to 32% (w/w) and increasing with the particle size. Particles with sizes from about 250 to 820 nm and low polydispersity were prepared with good reproducibility; the polymer concentration (at constant surfactant concentration) governed the particle size. The large particles with a high loading ( approximately 30%) showed under in vitro conditions a slow release over 24-30 h, the medium sized carriers (loading of approximately 13%) released the drug over about 15 h, whereas the small particles with small loading ( approximately 7%) exhibited a rapid release over a couple of hours. It seems that the drug release rate is related to the state (crystallized or dispersed) of the drug incorporated in the polymer matrix.