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环境科学与管理 1980年第9期 142-148页

作者： m. b. EVANS 陆妙琴

讨论了需要一个基本固定相或参比固定相来鉴别固定相的方法的局限性。为了克服这些问题,提出了一个新的方法,该法是以测定分子保留指数和所选定的官能团的△me值为主。△me值取决于液相的组成、担体的性质以及液相的负荷。

关键词：固定相极性吸附性表面性质保留指数担体保留值饱和脂肪族烃烷烃液相

Designing the new generation of intelligent biocompatible carriers for protein and peptide delivery

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Acta Pharmaceutica Sinica b 2018年第2期8卷 147-164页

作者： Angela m.Wagner margaret P.Gran Nicholas A.Peppas mcKetta Department of Chemical Engineering The University of Texas at Austin Institute for biomaterials Drug Delivery and Regenerative Medicine The University of Texas at Austin Department of biomedical Engineering The University of Texas at Austin Department of Pediatrics Dell Medical School The University of Texas at Austin Department of Surgery and Perioperative Care Dell Medical School The University of Texas at Austin Division of Pharmaceutics College of Pharmacy The University of Texas at Austin

Therapeutic proteins and peptides have revolutionized treatment for a number of diseases, and the expected increase in macromolecule-based therapies brings a new set of challenges for the pharmaceutics field. Due to their poor stability, large molecular weight, and poor transport properties,therapeutic proteins and peptides are predominantly limited to parenteral administration. The short serum half-lives typically require frequent injections to maintain an effective dose, and patient compliance is a growing issue as therapeutic protein treatments become more widely available. A number of studies have underscored the relationship of subcutaneous injections with patient non-adherence, estimating that over half of insulin-dependent adults intentionally skip injections. The development of oral formulations has the potential to address some issues associated with non-adherence including the interference with daily activities, embarrassment, and injection pain. Oral delivery can also help to eliminate the adverse effects and scar tissue buildup associated with repeated injections. However, there are several major challenges associated with oral delivery of proteins and peptides, such as the instability in the gastrointestinal(GI)tract, low permeability, and a narrow absorption window in the intestine. This review provides a detailed overview of the oral delivery route and associated challenges. Recent advances in formulation and drugdelivery technologies to enhance bioavailability are discussed, including the co-administration of compounds to alter conditions in the GI tract, the modification of the macromolecule physicochemical properties, and the use of improved targeted and controlled release carriers.

关键词： Oral delivery Hydrogels Protein delivery Peptide delivery Carbohydrates mucoadhesion

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Utilizing Geospatial Tools to Assign Unique Identifiers to Water bodies in a Low-Income Country

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Journal of Water Resource and Protection 2021年第3期13卷 236-253页

作者： Abubakarr S. mansaray Abdulai barrie Eva b. m. Jabati mohamed S. E. Juanah Kyran J. Ganda Oklahoma Water Resources Center Division of Agricultural Science and Natural Resources Oklahoma State University Stillwater Oklahoma USA Energy Sector Utility Reform Project Energy Distribution and Supply Authority Government of Sierra Leone Freetown Sierra Leone Institute of Environmental management and Quality Control School of Environmental Science Njala University Njala Sierra Leone National Water Resource management Agency Government of Sierra Leone Freetown Sierra Leone

Inland waters support the growth of several sectors including mining, agriculture, and health. This makes it crucial to have sustainable quantity and quality through conservation practices. Achieving sustainability requires information on the spatial distribution of water bodies. This requirement is particularly critical in low-income nations where dependence on natural resources is a key driver to economic growth. Unfortunately, these nations lack the resources to promote costly waterbody characterization. This study pre-sents a cost-effective approach in assigning Unique Identifiers (UIDs) that define locations and characteristics of rivers and streams. Our objective is to develop a scheme that can be used to identify and characterize rivers and streams in a nation. We utilized an open-source Digital Elevation model (DEm) of NASA’s ASTER satellite and the hydrology tool in ArcGIS 10.7.1. The DEm was imported to ArcGIS followed by delineation of hydrologic regions, subregions, and stream orders. Each stream segment was given a UID based on its region and Strahler’s stream order system. We present a case study analysis for two regions within Sierra Leone using water quality data of selected rivers and streams. These will lay the foundation for a nationwide coding exercise and provide a useful reference for water resource practitioners.

关键词： River Stream Unique Identifier Remote Sensing GIS Water Quality

cffdrs: an R package for the Canadian Forest Fire Danger Rating System

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Ecological Processes 2017年第1期6卷 30-40页

作者： Xianli Wang b.mike Wotton Alan S.Cantin marc-AndréParisien Kerry Anderson brett moore mike D.Flannigan Great Lakes Forestry Centre Canadian Forest ServiceNatural Resources Canada1219 Queen Street EastSault Ste.MarieON P6A 2E5Canada Department of Renewable Resources University of Alberta751 General Service BuildingEdmontonAB T6G 2H1Canada Faculty of Forestry University of Toronto33 Willcocks St.TorontoON M5S 3B3Canada Northern Forestry Centre Canadian Forest ServiceNatural Resources Canada5320-122nd StreetEdmontonAB T6H 3S5Canada

Introduction:The Canadian Forest Fire Danger Rating System(CFFDRS)is a globally known wildland fire risk assessment system,and two major components,the fire weather index system and the fire behavior prediction system,have been extensively used both nationally and internationally to aid operational wildland fire decision ***:In this paper,we present an overview of an R package cffdrs,which is developed to calculate components of the CFFDRS,and highlight some of its *** particular,we demonstrate how these functions could be used for large data *** and Discussion:With this cffdrs package,we provide a portal for not only a collection of R functions dealing with all available components in CFFDRS but also a platform for various additional developments that are useful for the understanding of fire occurrence and *** is the first time that all relevant CFFDRS methods are incorporated into the same platform,which can be accessed by both the management and research communities.

关键词： Fire behavior prediction system Fire weather index system Forest fire Forest fire risk Fuel moisture Landscape ecology

SUbORDINATION PROPERTIES OF mULTIVALENT FUNCTIONS INVOLVING AN EXTENDED FRACTIONAL DIFFERINTEGRAL OPERATOR

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Acta mathematica Scientia 2014年第2期34卷 367-379页

作者： mohamed K.AOUF Teodor bULbOACA Rabha m.EL-ASHWASH Department of mathematics Faculty of ScienceMansoura University Faculty of mathematics and Computer Science Babes-Bolyai University

The object of this article is to investigate inclusion, radius, and other various properties of subclasses of multivalent analytic functions, which are defined by using an extended version of the Owa-Srivastava fracti... 详细信息

关键词： Analytic functions p-valent functions meromorphic functions differintegraloperator differential subordination

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1GHz带宽的体波布喇格元件

压电与声光 1983年第6期 79-85页

作者： m.J.b.Scanlan ,王德芳

本文概述了1GHz带宽的体波布喇格元件的设计和生产.这些元件是将LiNbO3换能器以10个为一批一起粘贴到LiNbO3主体上制作而成的.介绍了带宽、效率、反射损耗、功率控制能力和烧毁功率的一些结果.

关键词：声换能器分辨力响应曲线声学器件反射损耗地震波体波

Effects of annealing temperature on shape transformation and optical properties of germanium quantum dots

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Chinese Physics b 2015年第2期24卷 459-466页

作者： Alireza Samavati Z.Othaman S.K.Ghoshal m.K.mustafa Ibn Sina Institute for Fundamental Science Studies Universiti Teknologi Malaysia Advanced Optical material Research Group Department of PhysicsFaculty of ScienceUniversiti Teknologi Malaysia Faculty of Science Technology and Human Development Universiti Tun Hussein Onn Malaysia

The influences of thermal annealing on the structural and optical features of radio frequency（rf） magnetron sputtered self-assembled Ge quantum dots（QDs） on Si（100） are *** oriented structures of Ge along the（220） and（111） directions together with peak shift and reduced strain（4.9%to 2.7%） due to post-annealing at 650 ℃ are discerned from x-ray differaction（XRD） *** force microscopy（AFm） images for both pre-annealed and post-annealed（650 ℃） samples reveal pyramidal-shaped QDs（density - 0.26×10^11 cm^-2） and dome-shape morphologies with relatively high density - 0.92×10^11 cm^-2,*** shape transformation is attributed to the mechanism of inter-diffusion of Si in Ge interfacial intermixing and strain *** annealing temperature assisted QDs structural evolution is explained using the theory of nucleation and growth kinetics where free energy minimization plays a pivotal *** observed red-shift - 0.05 eV in addition to the narrowing of the photoluminescence peaks results from thermal annealing,and is related to the effect of quantum ***,the appearance of a blue-violet emission peak is ascribed to the recombination of the localized electrons in the Ge-QDs/SiO2 or GeOx and holes in the ground state of Ge *** spectra of both samples exhibit an intense Ge-Ge optical phonon mode which shifts towards higher frequency compared with those of the bulk *** experimental Raman profile is fitted to the models of phonon confinement and size distribution combined with phonon confinement to estimate the mean dot sizes.A correlation between thermal annealing and modifications of the structural and optical behavior of Ge QDs is *** growth of Ge QDs with superior properties suitable for optoelectronic applications is demonstrated.

关键词： Ge QDs sputtering surface morphology optical properties

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Classification of briquettes Selection Criteria Using Principal Components Analysis Approach

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Journal of Power and Energy Engineering 2022年第6期10卷 14-26页

作者： Denis O. Kiobia Yusto m. Yustas Werenfrid m. Tarimo Susan A. mbacho Nelson R. makange Avitus T. Kashaija Erasto b. mukama Festo R. Silungwe School of Engineering and Technology (SoET) Sokoine University of Agriculture Morogoro Tanzania

The briquettes have the potential to reduce reliance on charcoal and firewood while addressing employment issues for youths and women through briquette-making value chain components. However, the marketing that would increase the acceptance of the briquettes requires an essential understanding of the briquettes’ critical selection criteria considered by potential briquette users. This study assesses the classes of briquette energy and their preferences. The study specifically investigated the following: 1) level of interest in briquette’s geometric shapes, 2) classes for briquette geometric shapes 3) class components leading to purchasing the briquettes. A baseline survey was conducted, which included 330 households in the morogoro district’s urban, peri-urban, and rural communities. The study used a snowball technique to meet with respondents, especially in families with youth and women. Securing information in objectives one and two used the five Likert scales (Strongly Agree, Agree, Neutral, Disagree, and strongly disagree). In contrast, objective three utilized the five Likert scales of 1, 2, 3, 4, and 5 in the order of importance. The Principal Component Analysis (PCA) method assisted in classification and interpreting the motive behind preferences. The results found that the motive behind the shape preferences was in two categories, each including three principal components. The categories are 1) geometric shapes: round, long, and circular/plate forms, and 2) purchasing influences: performance, attractiveness, and personal capacity. Therefore, the briquettes with technically improved round shapes produced based on the performance factors are recommended for adoption and marketability.

关键词： Preference biomass Environment Charcoal Wastes