Optical and structural properties of MOVPE grown GaxIn1−xAs/InP strained multiple quantum well atructures

This paper presents a study of the structural and optical properties of strained GaInAs/ InP multiple quantum well (MQW) structures fabricated by LP-MOVPE. The composition of the Ga _x In_1−x As films ranged fromx = 0.17 tox = 1.0 and was determined by sputtered neutral mass spectrometry (SNMS) on thick layers. The structures of the MQW samples with well widths from 1.5 to 5 nm were investigated by high resolution x-ray diffraction (HR-XRD). Simulations of the diffraction patterns showed that transition layers of approximately 2 monolayer (ML) thickness with high lattice mismatch exist at the interfaces. Photoluminescence (PL) measurements indicate well widths of a multiple of a monolayer with local variations of one monolayer. The PL peak energies vary smoothly with the Ga concentration. These results were confirmed by optical absorption measurements.     

某难选铅锌矿石浮选分离新工艺试验研究

针对某难选铅锌矿的矿石性质，进行了较为系统的小型试验研究。结果表明：在铅循环中采用Bx SN—9^#组合捕收剂、石灰 ZL—01组合抑制剂，在锌循环中采用捕收剂磁处理浮选技术等措施，可以较好地解决该难选矿的浮选分离问题。     

含淀粉聚乙烯膜的时控光降解研究

使用复合光降解剂，得到了可光降解的生物降解膜。对膜的光降解进行了考察，并对影响光降解的因素进行了讨论，结果表明，我们所制得的膜是一种较好的时控光降解膜。     

In_（0．2）Ga_（0．8）As／GaAs应变多量子阱结构的光调制反射和热调制反射谱的研究

对Ｉｎ（０．２）Ｇａ（０．８）Ａｓ／ＧａＡｓ应变多量子阱在７７Ｋ下的光调制反射谱（ＰＲ）和热调制反射谱（ＴＲ）进行了实验研究．对ＰＲ结果的线形拟合指认了应变多量子阱中子能级的跃迁，并与理论计算结果作了比较．实验对比确认ＰＲ中１１Ｈ、１３Ｈ等跃迁结构为非耦合态、具有电场调制机构的一阶微商性质．而１１Ｌ、３１Ｈ、２２Ｈ等跃迁结构为阶间耦合态，对这些隧穿耦合的低场调制产生三阶微商特性．     

二烷基硫代磷酸铵的捕收性能

本文研究了二烷基硫代磷酸铵（ＲＯ）２ＰＳＯＮＨ４（Ｒ＝乙基、丁基、己基、烯丙烯）系列捕收剂对非硫化矿孔雀石、锡石、赤铁矿、白铅矿、方解石和菱锌矿的浮选性能，并就药剂结构与性能关系进行了分析讨论．     

松香及其衍生物在浮选分离中的应用

介绍了松香的来源、化学组成及理化性质；讨论了松香及其衍生物在非硫化物矿浮选分离、有色金属离子的浮选分离以及从水溶液中浮选分离有机物等方面的应用情况。     

Deorthogonalization of ODS-CDMA QPSK by AM/PM Nonlinearity

When using a conventional demodulator, a sufficient condition to maintain ODS-CDMA codeword orthogonality is constant relative channel amplitude over the codeword duration. When transmitted over a memoryless, AM/PM nonlinearity channel, the chip-to-chip fluctuating amplitude of a composite ODS-CDMA QPSK waveform produces a chip-to-chip fluctuating phase that deorthogonalizes the ODS-CDMA codewords, resulting in an additional multiple access self-interference similar to that found in asynchronous DS-CDMA. For ODS-CDMA QPSK in an AM/PM nonlinearity channel, we utilize the Central Limit Theorem, derive, and evaluate: (i) an expression for the signal-to-distortion ratio at the demodulator output, (ii) an expression for the uncoded bit error probability, and (iii) an upper bound on the convolutionally-coded bit error probability. We find that the degradation to BER depends on both the AM/PM nonlinearity slope and the ODS-CDMA channel loading.     

Stereological estimation of the total volume of MR visible brain lesions in patients with multiple sclerosis

Point counting represents a convenient and efficient technique for estimating the area of transects through multiple sclerosis (MS) lesions on magnetic resonance (MR) images obtained for sections through the brain. When sectioning has been performed according to the Cavalieri method, unbiased estimates of the total volume of MR-visible MS plaques can be obtained with a precision of 3–5% in 5–10 min.     

硫化钠在黑白钨加温精选中的应用研究

介绍了柿竹园黑白钨混合粗精矿加温精选中 ,添加硫化钠与水玻璃混合剂比单一添加水玻璃能更有效地使白钨矿与萤石等含钙矿物及脉石矿物分离。论述了硫化钠在加温精选中的作用效果并探讨了其作用机理     

大庆油田水平井分流压裂技术

水平井分流压裂的技术原理是将水平井的水平段分成若干个单元，在每个单元的最佳部位进行射孔，每段的射孔数由孔径、单元数、设计施工排量等参数决定，射孔方案为压裂方案的有机组成部分。大庆油田已有5口水平井实施分流压裂，根据油层厚度分为两类：裂缝限制在油层内和裂缝穿透隔层贯穿多个薄油层。通过肇57-平35井和肇57-平33井进行的分流压裂贯穿多个油层现场试验，介绍了大庆油田水平井分流压裂的设计方法、压裂液体系、现场施工控制方法和效果分析方法。微地震裂缝监测结果表明，在最大施工排量7．5m^3／mim条件下，一次施工形成3～4条裂缝，加砂量最大达到75m^3（陶粒），平均砂比达到35％以上。水平井采用分流压裂技术施工后，初期产能可达到相邻直井压裂后产能的2．0倍以上。如何检测裂缝是否穿透了隔层并贯穿多个油层，是指导水平井分流压裂技术的选井选层，提高压裂效果的关键技术。图8表2参2。