Analytical coupled-wave model for photonic crystal quantum cascade lasers

A coupled-wave model is developed for photonic-crystal quantum cascade lasers. The analytical model provides an efficient analysis of full three-dimensional large-area device structure, and the validity is confirmed via simulations and previous experimental results.Comment: 21 pages and 8 figure

First-line single agent treatment with gefitinib in patients with advanced non-small-cell lung cancer

<p>Abstract</p> <p>Background</p> <p>Lung cancer is a malignant carcinoma which has the highest morbidity and mortality in Chinese population. Gefitinib, a tyrosine kinase (TK) inhibitor of epidermal growth factor receptor (EGFR), displays anti-tumor activity. The present data regarding first-line treatment with single agent gefitinib against non-small-cell lung cancer (NSCLC) in Chinese population are not sufficient.</p> <p>Purpose</p> <p>To assess the efficacy and toxicity of gefitinib in Chinese patients with advanced non-small-cell lung cancer (NSCLC), a study of single agent treatment with gefitinib in Chinese patients was conducted.</p> <p>Methods</p> <p>45 patients with advanced NSCLC were treated with gefitinib (250 mg daily) until the disease progression or intolerable toxicity.</p> <p>Results</p> <p>Among the 45 patients, 15 patients achieved partial response (PR), 17 patients experienced stable disease (SD), and 13 patients developed progression disease (PD). None of the patients achieved complete response (CR). The tumor response rate and disease control rate was 33% and 71.1%, respectively. Symptom remission rate was 72.5%, and median remission time was 8 days. Median overall survival and median progression-free survival was 15.3 months and 6.0 months, respectively. The main induced toxicities by gefitinib were skin rash and diarrhea (53.3% and 33.3%, respectively). The minor induced toxicities included dehydration and pruritus of skin (26.7% and 22.2%, respectively). In addition, hepatic toxicity and oral ulceration occurred in few patients (6.7% and 4.4%2, respectively).</p> <p>Conclusions</p> <p>Single agent treatment with gefitinib is effective and well tolerated in Chinese patients with advanced NSCLC.</p

Effect of Quenching Process on Microstructure and performance of High-Boron High-Speed Steel

The effects of quenching process on microstructure and hardness of High-Boron High-Speed Steel (HB-HSS)containing 0.4%C-6.0%Cr-4.0%Mo-1.0%V-1.0%Si-0.5Mn-x%B-y%Al (x=1.0, 1.5, 2.0, y=1.0, 2.0, 3.0)were investigated by means of optical microscopy (OM), scanning electron microscopy (SEM), X-raydiffraction (XRD), and Rockwell hardness tester. The experimental results indicate that the quenchingmicrostructure of HB-HSS consists of α-Fe, M2(B, C), M7(B, C)3 and a few of M23(C, B)6。With the increaseof quenching temperature, the net structure of borocarbides is damaged and the borocarbides are evenlydistributed in the matrix. When the quenching temperature is 1050 °C, the Rockwell hardness of HB-HSSincreases with the increase of boron content. The Rockwell hardness of HB-HSS decreases with the increaseof aluminum content. When the quenching temperature is 1050 °C, the aluminum content is 1.0% and boroncontent is 1.0%-2.0%, the combination of the microstructure and the hardness of HB-HSS is the best.Keywords: High-boron high-speed steel; Quenching microstructure; Borocarbide; Hardness

Combining Paleomagnetic and Re‐Os Isotope Data to Date Hydrocarbon Generation and Accumulation Processes

Unraveling the complex relationship between orogenesis and hydrocarbon formation and accumulation is challenging and is often hampered by physical and chemical overprints of younger events. The Permian reservoir in the Longmen Shan orogen, South China, is such an example, and its evolution has been hotly debated. In this study, we use a new combination of paleomagnetic dating analysis and Re–Os isotope dating to try to resolve this. Paleomagnetic dating of the hydrocarbon-host carbonate indicates two remagnetization events during: (a) the Late Triassic, and (b) the Middle Jurassic–Cretaceous. These two remagnetization events are shown to represent two distinct stages of hydrocarbon accumulation. The paleomagnetic estimates are supported by Re–Os dating of bitumen (∼264 Ma) and oil (∼94 Ma). The two different Re–Os ages are associated with two periods of oil generation. We interpret these data in terms of known geological processes: (a) the ∼260 Ma Dongwu large igneous province caused oil generation, and the Indosinian tectonic event caused the migration and accumulation; and (b) the Late Cretaceous Yanshan orogenic events promoted another generation and entrapment of oil in the same reservoir. This combined approach reliably tracks the sequence of oil generation and accumulation, even when the source rock is uncertain, and multi-phase accumulation and complex tectonism has occurred. Given that paleomagnetic and Re–Os dating are independent methods which can constrain multiple geological processes, when used together they have the potential to be universally applied