نتایج جستجو برای: 15 2113 hodchinson
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Problem statement: Santa Barbara Amorphous (SBA-15) is significant mesoporous silica with exclusive and important properties of highly ordered mesopores, hydrothermally stable and thick wall, profusely large surface area and huge pore volume which render it as promising catalyst for wide applications. However, the purely siliceous SBA-15 which lacks of acidity characteristic hinders its ideal c...
بسیاری از رنگهای آلی مانند رنگ کاتیونی متیلنبلو بهدلیل ساختار پیچیده آروماتیک و حلالیت بالا در آب، سمی، سرطانزا و غیر قابل تجزیه زیستی میباشند، لذا حذف آنها از پساب ضروری است. در این تحقیق، سیلیس نانوحفره SBA-15 بهروش هیدروترمال سنتز و سپس بهروش پساسنتزی با گروه تکشاخه آمینی (NH2-SBA-15) و دندریمرآمینی (MDA-SBA-15) عاملدار شد. اثر اصلاح سطح بر روی کارایی جذب رنگ متیلنبلو در سیستم نا...
Over the past decade, cloud services emerged as one of the most promising technologies in IT. Since cloud computing allows improving the quality of software and, at the same time, aims at reducing costs of operating software and hardware, more and more software is delivered as a service in the cloud. However, moving existing software applications to the cloud and making them behave as software ...
The variance of zt around its expected value E( gt ) in this particular generation is σ g(t) + σ 2 e(t). However, we usually don’t know the particular value of dt, which is assumed to be uncorrelated between generations (σ(dt, dt′) = 0), with mean 0 and variance σ d. Thus, the expected value of zt measured at a random time (e.g., the value of d is chosen at random) is μ+E( gt ) and the variance...
15.1. The First Law of Thermodynamics • Define the first law of thermodynamics. • Describe how conservation of energy relates to the first law of thermodynamics. • Identify instances of the first law of thermodynamics working in everyday situations, including biological metabolism. • Calculate changes in the internal energy of a system, after accounting for heat transfer and work done. 15.2. Th...
In the next Generation Networks like Mobile WiMAX, it is highly essential to create a market mechanism that would allow the customer to communicate with Network and negotiate a contract based on some QoS parameters like blocking probability, delay, arrival rate, spectral efficiency, resource allocation and price. However, the mechanisms, rather than technical-oriented scheme, that involve the u...
In this chapter I present an overview of the concepts and status of the science of weather and climate engineering. I begin by discussing the concepts of seeding clouds through glaciogenic and hygroscopic seeding. I review the status of research on these concepts for increasing rainfall, decreasing hail damage, and reducing hurricane intensity. Thereafter I present an overview of the concepts f...
پورفیرین ها یک ترکیب ماکروسیکل هترو اتم می باشند که نقش مهمی در زندگی موجودات زنده ایفا می کنند. به طور مثال هِم موجود در ساختار هموگلوبین که مسئول انتقال اکسیژن در خون است و کلروفیل که رنگدانه فتوسنتزی گیاهان به شمار می رود، نوعی پورفیرین می باشند. ساختار مولکولی پورفیرین ها ، متشکل از چهار واحد پیرولی است که به وسیله پل های مِتین به هم متصل شده اند. این ساختار در سال 1912 توسط کوستر پیشنهاد شد،...
Here we describe an approach, based upon a notion of problem similarity, that can be used when attempting to devise a heuristic for a given search problem (of a sort represented by graphs). The proposed approach relies on a change in perspective: instead of seeking a heuristic directly for a given problem PI, one seeks instead a rolp___21gm P2 easier to solve than PI and related to PI in a cert...
A problem with A* is that it fails to guarantee opt imal solutions when its heuristic, h, overestimates. Since optimal solutions are often desired and an underestimating h is not always available, we seek to remedy this. From a nonadmissible h an admissible one is generated using h's statistical properties. The new heuristic, hm, is obtained by inverting h wi th respect to its own least upper b...
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