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中国科学院大学学报 1985年第1期 1-6页

作者： k. T. Lu(graduate School USTC, Academia Sinica)

Ⅰ.Introduction A new feature of atomic spectroscopy is the use of well characterized atomic states as probes of interactions with their surroundings; c.g. atoms are now prepared by laser excitation in specific Rydberg levels, while earlier spectroscopy dealt with gases excited by a *** interacting environment includes (a) other atoms,molccules, ions or electrons,(b) external fields, and(c) electromagnetic fields such as laser, microwaves,and RF waves.

关键词： Spectroscopy Current Trends in Atomic

Noise Feedback Coding Revisited:Refurbished Legacy Codecs and New Coding Models

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ZTE Communications 2012年第2期10卷 34-44页

作者： Stéphane Ragot Balázs kvesi Alain Le guyader audiOvisual and sPEech foR quAlity(OPERA) Lab. Orange LabsLannionFrance

Noise feedback coding （NFC） has attracted renewed interest with the recent standardization of backward-compatible enhancements for ITU-T g.711 and g.722. It has also been revisited with the emergence of proprietary speech codecs, such as BV16, BV32, and SILk, that have structures different from CELP coding. In this article, we review NFC and describe a novel coding technique that optimally shapes coding noise in embedded pulse-code modulation （PCM） and embedded adaptive differential PCM （ADPCM）. We describe how this new technique was incorporated into the recent ITU-T g.711.1, g.711 App. III, and g.722 Annex B （g.722B） speech-coding standards.

关键词： speech coding noise shaping noise feedback coding g.711 g.722

Impact of Integrated Nutrient, Crop Residue and Tillage Management on Soil Aggregates and Organic Matter Fractions in Semiarid Subtropical Soil under Soybean-Wheat Rotation

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American Journal of Plant Sciences 2013年第11期4卷 2148-2164页

作者： Milkha S. Aulakh Ashok k. garg Shrvan kumar Department of Soil Science Punjab Agricultural University Ludhiana India krishi Vigyan kendra Punjab Agricultural University Patiala India MSkJ University of Agriculture and Technology Banda India

Various physical, chemical and biological soil properties in surface (0-5 cm) and subsurface (5-15 cm) soil were determined in a 4-year field experiment conducted at Punjab Agricultural University Ludhiana, India with sixteen treatments consisted of different combinations of fertilizer N (0, 20 and 25 kg N ha-1), P (0, 60 and 75 kg P2O5 ha-1), FYM (0 and 10 t·ha-1) and wheat (Triticum aestivum L.) residue (WR) (0 and 6 t·ha-1) applied to summer-grown soybean (glycine max L.) and fertilizer N (0, 120 and 150 kg N ha-1), P (0, 60 and 75 kg P2O5 ha-1), and soybean residue (SR) (0 and 3 t·ha-1) applied to winter-grown wheat crop continuously in both conventional tillage (CT) and conservation agriculture (CA), arranged in a split-split plot design with tillage system in main blocks, under irrigated subtropical conditions. Application of fertilizer N, P, FYM and crop residue (CR) significantly increased water stable aggregates and had profound effects in increasing the mean weight diameter as well as the formation of macro-aggregates, which were the highest in both surface (85%) and subsurface (81%) soil layers with application of 20 kg N + 60 kg P2O5 + 10 t FYM + 6 t WR ha-1 applied to soybean and 120 kg N + 60 kg P2O5 + 3 t SR ha-1 applied to wheat crop in CA, respectively, and were 83% and 77% in CT treatments after 2 years. Hence, better aggregation was found with 100% NP + FYM + CR, where macro-aggregates were greater than 50% of total soil mass. The same treatment also enhanced total organic C (TOC) from 3.8 g·kg-1 in no-NP-FYM-CR control to 5.8 g·kg-1 in surface layer and from 2.7 to 3.6 g·kg-1 in subsurface layer after 2 years leading to the 41% and 39% higher TOC stocks over CT-Control in 0-15 cm soil layers of CT and CA, respectively. The changes in TOC stocks after 4 years were 52% and 59%.

关键词： Soybean Conservation Agriculture Water Stable Aggregates Organic Matter Fractions

Heavy Mineral Potentiality and Alteration Studies for Ilmenite in Astaranga Beach Sands, District Puri, Odisha, India

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Journal of geoscience and Environment Protection 2015年第1期3卷 31-37页

作者： Sanuprava Mohapatra P. Behera S. k. Das P.g Department of geology Utkal University Bhubaneswar India Institute of Minerals and Materials Technology Bhubaneswar India

Fifteen beach sand samples were collected from a depth of 1mt at different locations of the Astaranga beach, Puri with an interval of 300 mts. The beach sand samples were studied for heavy mineral concentration at different location points and were subjected to scanning electron microscope studies for the mineral ilmenite. The percentage of total heavy mineral in Astaranga beach varies from 16.42% to 24.47%. The important minerals are ilmenite, rutile, zircon, sillimanite, garnet, monazite, pyroxene and others. For all samples a set of sieves bearing ASTM nos. 30, 40, 60, 80, 100, 120, 140, 170 and 200 corresponding to 0.59 mm, 0.42 mm, 0.25 mm, 0.177 mm, 0.149 mm, 0.125 mm, 0.105 mm, 0.088 mm and 0.074 mm respectively were used to separate different size fractions. The sieve mesh sizes vary from 0.59 mm to 0.74 mm. It was observed that maximum concentration of heavies was confined to +200 ASTM sieve or 0.74 mm. The total average heavy mineral concentration and light mineral concentration was found to be 20.07% and 79.49% respectively. The concentration percentage of different heavy minerals varied from higher to lower in the order like ilmenite, zircon, sillimanite, garnet, rutile, pyroxene, monazite and others. The ilmenite mineral in this area is found to have altered to secondary phases like pseudorutile, leucoxene and rutile along the fractures, cavities and grain boundaries. The alteration condition was observed as streaks, irregular patches, bands, and rim like structures around the ilmenite grains. Detailed study of alteration in ilmenite was carried out by Energy Dispersive Spectrometer (EDS) attached to Scanning Electron Microscope. The potentialities of heavies found at different locations of the Astaranga beach suggested a good source for the exploration. The alteration of the mineral ilmenite and high concentration of heavy minerals clearly pointed to the sedimentary environment and mechanical concentration process due to repeated wave action.

关键词： Alteration Astaranga Heavy Minerals Ilmenite SEM EDS

Monitoring Heavy Metals near Wastewater Facility in Delaware Inland Bays Tidal Canal

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Journal of Water Resource and Protection 2017年第8期9卷 985-998页

作者： Amy C. Cannon Lathadevi k. Chintapenta gulnihal Ozbay Department of Agriculture and Natural Resources Delaware State University Dover DE USA

NOAA National Status and Trends Mussel Watch Report indicate the Delaware Bay has regionally medium levels of Cd and high levels of Pb. Environment New Jersey, a non-profit environmental group, reported the Delaware River, providing drinking water to millions, as the fifth most-polluted river in the country. These concerns resulted in this study monitoring water quality conditions near a wastewater facility in Delaware. Physical water quality parameters were measured, along with heavy metals Cd and Pb. Mean metal levels were consistently low at the wastewater discharge (1.3 μg/L Cd, 5.1 μg/L Pb), and high at the control location (9.2 μg/L Cd and 11.5 μg/L of Pb). Relationships were observed between heavy metals, salinity and pH levels. Results suggest water treated by the facility does not pose heavy metal contamination risks to the Lewes Rehoboth Canal. Further studies are warranted to seek heavy metal sources at the control point, farthest from the waste water treatment facility.

关键词： Heavy Metals Cadmium Lead Receiving Waters Impacts Water Quality Monitoring and Assessment

The Efficiency of a p-n Solar Diode as a Function of the Recombination Velocity within the Depletion Layer

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Optics and Photonics Journal 2012年第4期2卷 326-331页

作者： Mohamed k. El-Adawi Najla S. Al-Shameri Physics Department College of Science for Girls Dammam University Dammam KSA Physics Department Faculty of Education Ain Shams University Cairo Egypt

The role of the carrier’s recombination velocity Si within the depletion Layer of p-n junction solar cell and the external bias voltage Va across the junction in determining the current density “J” through the cell is revealed. The unsteady carrier diffusion equation is solved under illumination conditions considering a source spectral function g(λ). The efficiency of the device as a function of Si , Va , g(λ) is obtained. Computations considering a silicon solar cell are given as an illustrative example.

关键词： Efficiency Diffusion Equation Recombination Velocity

Preparation and optimization of various parameters of enteric coated pellets using the Taguchi L9 orthogonal array design and their characterization

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Acta Pharmaceutica Sinica B 2011年第1期1卷 56-63页

作者： D.Shravani P.k.Lakshmi J.Balasubramaniam Department of Pharmaceutics G.Pulla Reddy College of PharmacyHyderabad 500028Andhra PradeshIndia Formulation Research and Development CentreRA Chem Pharma LimitedHyderabad 500076Andhra

Duloxetine hydrochloride enteric coated pellets were formulated using fluidized *** separate layers,the drug layer,the barrier layer,and the enteric layer,were coated onto the inert core *** pellets were optimized with the acid resistance and drug release in simulated intestinal fluid as the process parameters,using the Taguchi L9 orthogonal *** other properties,such as surface morphology,bulk and tapped density,Hausner’s ratio,hardness,friability,yield of pellets,moisture content,and particle size distribution,were also studied in the optimized *** concentration of the enteric polymer played a vital role in acid resistance,while the type of enteric polymer affected the drug release in simulated intestinal *** both cases,it was determined that binder polymer concentration was not affected *** comparisons between the optimized pellets and a market formulation yielded f1 and f2 values within a range of 4–5 and 60–65,*** month stability studies,conducted at accelerated conditions,showed the optimized pellets to be *** plays an important role in optimizing parameters,and optimization of duloxetine hydrochloride can be achieved with minimal trials.

关键词： Duloxetine Pellet Enteric polymer Barrier layer Taguchi L9 orthogonal array

Manpower Systems Operating under Heavy and Light Tailed Inter-Exit Time Distributions

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Applied Mathematics 2014年第2期5卷 285-291页

作者： R. Sivasamy P. Tirupathi Rao k. Thaga Department of Statistics Pondicherry University Puducherry India Statistics Department University of Botswana Gaborone Botswana

This paper considers a Manpower system where “exits” of employed personnel produce some wastage or loss. This system monitors these wastages over the sequence of exit epochs {t0 = 0 and tk;k = 1, 2,…} that form a recurrent process and admit recruitment when the cumulative loss of man hours crosses a threshold level Y, which is also called the breakdown level. It is assumed that the inter-exit times Tk = tk-1 - tk, k = 1, 2,… are independent and identically distributed random variables with a common cumulative distribution function (CDF) B(t) = P(Tk t) which has a tail 1 – B(t) behaving like t-v with 1 v as t → ∞. The amounts {Xk} of wastages incurred during these inter-exit times {Tk} are independent and identically distributed random variables with CDF P(Xk X) = g(x) and Y is distributed, independently of {Xk} and {tk}, as an exponentiated exponential law with CDF H(y) = P(Y y) = (1 - e-λy)n. The mean waiting time to break down of the system has been obtained assuming B(t) to be heavy tailed and as well as light tailed. For the exponential case of g(x), a comparative study has also been made between heavy tailed mean waiting time to break down and light tailed mean waiting time to break down values. The recruitment policy operating under the heavy tailed case is shown to be more economical in all types of manpower systems.

关键词： Manpower System Recruitment Policy Inter-Exit Time Wastage Waiting Time to Breakdown Heavy Tailed Inter-Exit Time Distribution and Light Tailed Distribution

Antibiotics for eradicating meningococcal carriages:Network meta-analysis and investigation of evidence inconsistency

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World Journal of Meta-Analysis 2016年第4期4卷 77-87页

作者： Asmaa S Abdelhamid Yoon k Loke Ibrahim Abubakar Fujian Song Norwich Medical School University of East Anglia Institute of Epidemiology and Health University College of London

AIM To compare different antibiotics for eradicating the carriage of Neisseria meningitidis(***),and to investigate heterogeneity and evidence *** From a search of Pub Med and published systematic reviews,we identified 23 trials evaluating 15 antibiotics that could be connected in a trial *** outcome of interest is the eradication of *** used Win BUgS to conduct random-effects,mixed treatment *** and evidence inconsistency was investigated by meta-regression modelling and examining characteristics of trial participants and interventions *** Rifampin,ciprofloxacin,minocycline,ceftriaxone,and azythromycin were statistically significantly(Pg the best was 67.0%for a combination of rifampin and minocycline,25.0%for ceftriaxone,1.7%for azythromycin,and below 1%for the remaining *** inconsistency between the direct and indirect estimates was observed for the comparison of rifampin and ciprofloxacin(Pge of prophylactic antibiotic regimens are effective for eradicating meningococcal carriages,and treatment choice will depend on the individual priorities of the patients and *** clinical situations where complete eradication is considered to be of the utmost importance,a combination of rifampin and minocycline seems to offer the highest likelihood of *** as a single intramuscular injection is also likely to be more effective as compared with the other two antibiotics(ciprofloxacin or rifampin)recommended by the current guidelines.

关键词： Chemoprophylaxis Antibiotics Nersseria meningitidis Meningococcal infection Network metaanalysis