Technology That Separates Things Base on Density Continuously

SPECTROSCOPY | Absolute Optical Frequency Metrology

S.T. Cundiff , L. Hollberg , in Encyclopedia of Modern Optics, 2005

Outlook

Three separate technologies have now reached a level of maturity that it is possible to build high-performance optical-frequency standards and clocks. The essential achievements are: laser cooling and trapping of atoms (first proposed by Wineland and Dehmelt, and Hänsch and Schawlow), highly stabilized narrow-linewidth cw lasers, and femtosecond optical frequency combs. Combining these key ingredients, we can construct an optical atomic clock as shown schematically in Figure 9.

Figure 9. Simplified schematic of an optical clock.

Here, for comparison with Figure 1, the cold atoms or single ion provide the narrow atomic resonance, the cw laser serves as the local oscillator to probe the resonance, and the femto-comb serves as the counter. Optical frequency standards of the future are expected to provide orders of magnitude better stability and improved accuracy over the existing atomic frequency standards that now use microwave transitions in atoms. As described in the previous section, frequency combs produced by femtosecond lasers can directly measure the frequency of a stable laser locked to an atomic transition relative to a known microwave frequency standard. This gives fundamental information about the atomic energy levels, and structure, and allows comparisons between different elements. However, to take advantage of the high stability of the optical references we run the system as an optical clock (Figure 9) where the stable laser and the femto-comb are locked to the atomic resonance, and the clock output comes as pulses at the repetition rate (e.g., 1   GHz) of the femtosecond mode-locked laser. With a judicious choice of control parameters it is possible to have the pulse repetition frequency, i.e., the clock output, at an exact subharmonic of the optical transition frequency. It is intriguing to note that a portable optical clock could measure time and length at the same time.

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Microfabrication technologies used for creating smart devices for industrial applications

José M. Quero , ... Carmen Aracil , in Smart Sensors and MEMs (Second Edition), 2018

11.4.3.2 Dry etching

Three separate technologies are included in this category: reactive ion etching (RIE), sputter etching, and vapor-phase etching. They generally consist of an advanced etching process that yields patterns with a high resolution.

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Reactive ion etching: In this process, plasma drives a chemical reaction to remove materials. There is also a physical process similar to that of sputtering deposition, but which results in an etching. It is a complex task because chemical and physical etchings have to be balanced, so there are many parameters to be adjusted.

A particular version of RIE is deep RIE. In this process, etch depths of hundreds of microns can be achieved with almost vertical sidewalls and therefore high aspect ratio structures can be achieved. The technology is based on the process patented by Bosch (Laermer and Schilp, 2006). Two different gas compositions are involved. The first one etches the substrate, and the second creates a polymer on the surface of the substrate that produces the passivation of the sidewalls. Because the polymer protects the sidewalls from etching, etching aspect ratios of 50:1 can be achieved.

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Sputter etching: This process is very similar to RIE, but there are no reactive ions and it is based on a sputtering process where the substrate is subject to ion bombardment, instead of the material target.

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Vapor-phase etching: This is a kind of isotropic etching, which is a similar process to RIE, although it requires a simpler setup. The wafer is also placed inside a chamber into which one or more gases are introduced. The target material is superficially dissolved because of a chemical reaction with the gas molecules. The two most common reactive vapor-phase etching technologies are silicon etching using xenon difluoride (XeF₂) and silicon dioxide etching using hydrogen fluoride (HF). Suspended and 3D structures can be obtained.

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Role of Blockchain Technology in IoT Applications

Arnab Banerjee , in Advances in Computers, 2019

6 Conclusion

IoT and blockchain as separate technologies are restricted in their applications in any field. In supply chain and logistics, it can derive significant benefit with the combined architecture of IOT, blockchain and other supply chain systems like ERP. The architecture presented is generic and can help any type of supply chain orchestration and few specifics are highlighted and discussed. The chapter individually discusses the problem faced today in agri supply chain, auto supply chain, product or order tracking, traceability and recall, counterfeiting, digital homes, manufacturing and distribution supply chain and how these challenges can be solved with the IOT Blockchain combination. Ranging from generic supply chain flows to specific agri or automotive supply chain the benefits are similar in eliminating the intermediaries, bringing in transparency and establishing provenance or tracking it to the detailed level. Blockchain and IOT as a technology are maturing and growing together. They are codependent on one another and stands maximum changes of development with both being together. IOT desperately needs the blockchain's features as it brings in security, immutability and smart contracts while the blockchain is in need of IOT to channelize the feed of data to convert every aspect as a big-time opportunity for supply chain to become more effective. IOT Blockchain combination will revolutionize the supply chain in the way the partners interact today. The combination will add value to products, invoke trust among partners, reduce supply chain cost, improve process efficiency, avoid information voids and empower customers.

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Thermochemically regenerative flow batteries for solar electricity generation and storage

Abraham Kribus , Michael Epstein , in Ultra-High Temperature Thermal Energy Storage, Transfer and Conversion, 2021

2.5 Discussion

A solar hybrid power plant with integrated TECS combines two separate technologies, namely electrochemical battery storage and CSP high-temperature solar thermochemistry. It may offer major advantages compared with the existing storage solution in CSP plants: flexible operation from storage with an electrochemical cell without a thermal inertia and efficiency penalty of a steam turbine; much and simpler smaller storage tanks; and a much higher conversion efficiency as presented here. The upper limit on efficiency derived by analysis of an ideal system model is very high and is close to the Carnot limit for the same temperature. The more realistic analysis with engineering considerations and the realistic losses of main components has shown estimated efficiency from solar radiation to electricity of up to 35%, which is significantly higher than the efficiency of leading industrial scale solar technologies. The solar efficiency is similar to some other advanced solar technologies, which, however, do not offer a storage option. From the perspective of expected performance, the TECS concept then seems very attractive and worthy of further development.

The plant description and analysis has shown that the implementation of a solar hybrid power plant with integrated TECS is based mostly on existing technologies or at least on technologies that have been demonstrated in research at reasonable scale. However, there are many aspects of technology and system integration that need validation and effective engineering solutions. For example, if the concept is implemented with solid materials as described here, then industrially known solutions must be implemented and adapted for the transportation and handling of solids throughout a plant. Reactor and quencher components, even though similar to previously demonstrated technologies, must be validated and adapted to the specific materials, reactions, and operating conditions in this cycle. After the plant engineering is further developed, an economic analysis should be done to compare not only performance but also cost effectiveness of this solution with those of other solar plants and more broadly to compare additional nonsolar energy conversion and storage technologies.

An additional aspect of this approach is the need to seek other active materials that may provide better solutions. The three material systems presented here were selected for specific reasons: the Na–S system is fully liquid, making its conversion into a flow battery very convenient; the zinc–air–carbon system has been extensively researched leading to available knowledge and demonstrated technology for the reduction reaction and quenching; and the lithium–air system promises the highest storage density and efficiency. However, many other candidate materials are available and should be investigated. Advantages may be found not necessarily in terms of efficiency, but possibly in other aspects such as easier handling, better safety, and lower reaction temperatures. A successful technology eventually is the one that offers the best overall balance of performance, cost, and reliability, and further research is needed to find the materials that offer the best balance.

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Information Technology–Operation Technology Convergence

K.L.S. Sharma , in Overview of Industrial Process Automation (Second Edition), 2017

20.7 Summary

Over the past decades, most industries have developed and managed OT and IT as two different entities, maintaining separate technology, standards, governance methods, and organizational units. However, over the years, OT has been progressively migrating to IT-like technologies. In the light of this, the convergence of IT and OT is expected to bring clear and tangible advantages to companies on cost and risk reductions, enhanced performance, increased flexibility, etc. A prerequisite to achieve these benefits is an understanding of the strategic, organizational, and technological issues involved in both IT and OT and implementation of their convergence for uniform strategies, governing models, security, resource use, etc. along with reskilling of people to know about the requirements of both disciplines.

Successful IT-OT convergence helps companies exploit the potentials hidden in their supply chain by streamlining processes, increasing data transparency, and allowing for better and quicker decision making. New ideas and concepts are developing around IT-OT, providing major opportunities to leverage IT know-how to the production floor. This can make a difference when competing with peers. Considering all of this, IT-OT convergence standard (ISA 95 or IEC 62264) is developed for the interoperability of systems developed by vendors.

The chapter also briefly discussed IoT, IIoT, and Industry 4.0 as an extension of IT-OT integration.

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Exergy and industrial ecology

Ibrahim Dincer , Marc A. Rosen , in Exergy (Third Edition), 2021

23.3.2 Integrated systems

The efficiency of integrated or combined technologies (e.g., cogeneration) can be evaluated and compared by examining the depletion numbers D _p for the separate and combined technologies (see Fig. 23.1).

Fig. 23.1. Input and output exergy rates for separate and combined technologies to produce two products.

The consumption of nonrenewable energy resources corresponds to lower depletion numbers (see Eq. 23.2). Consequently, the depletion number for an advanced combined technology D _p ^(comb) should be lower than the weighted sum of the depletion numbers D _p ^(sep) for the separate technologies. For the system in Fig. 23.1, D _p ^(sep) is expressible as follows:

(23.4) $D_{\mathrm{p}}^{\left(\mathrm{sep}\right)}=\frac{\stackrel{.}{E}{x}_{\mathrm{p}1}^{\text{comb}}}{\stackrel{.}{E}{x}_{\mathrm{p}1}^{\text{comb}}+\stackrel{.}{E}{x}_{\mathrm{p}2}^{\text{comb}}}{D}_{\mathrm{p}}^{\left(1\right)}+\frac{\stackrel{.}{E}{x}_{\mathrm{p}2}^{\text{comb}}}{\stackrel{.}{E}{x}_{\mathrm{p}1}^{\text{comb}}+\stackrel{.}{E}{x}_{\mathrm{p}2}^{\text{comb}}}{D}_{\mathrm{p}}^{\left(2\right)}$

where D _p ⁽¹⁾ and D _p ⁽²⁾ are depletion numbers for two separate technologies and $\stackrel{.}{E}{x}_{\mathrm{p}1}^{\text{comb}}$ and $\stackrel{.}{E}{x}_{\mathrm{p}2}^{\text{comb}}$ are the rates of output exergy flows for products 1 and 2, respectively.

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Hybrid Abrasive Waterjet and Milling Process

Francesco Viganò , ... Massimiliano Annoni , in Hybrid Machining, 2018

Abstract

Machining specially shaped geometrical features on hard-to-machine materials is an important task to solve nowadays in manufacturing research. In some cases, two separate technologies can operate on a single feature, exploiting the best performances of both in an optimized process chain. Deep pocket milling is an emblematic case where a combination of Abrasive Water Jet (AWJ) and Milling technology can be used as a close sequential manufacturing strategy. The use of AWJ technology for milling purposes is discussed in this chapter, considering its advantages and limits compared to conventional Milling. It highlights the potential of coupling these two manufacturing technologies, even into a single hybrid machining center. A case study on hybrid deep pocket milling on Grade 5 Ti-alloy Ti6Al4V (Ti-64), developed at Politecnico di Milano, is discussed in this chapter.

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CdTe Solar Cells

Tom Baines , ... Jonathan D. Major , in A Comprehensive Guide to Solar Energy Systems, 2018

10.2.4 The Chloride Process

What is widely referred to as the chloride treatment step is typically essential to the production of functional CdTe solar cells. Indeed, barring single crystal cell exceptions [40] (which may to an extend be considered a separate technology entirely), no cell reported has exceeded 10% without some form of chloride treatment. It was first developed by Basol [41] using an electrochemical process, and the use of chlorine appears to have emerged from its prior use to photosensitize CdS films. Otherwise it is hard to understand the logical leap to applying Cl which, being a group VII element, one would initially assume would be an n-type dopant, to achieve p-type character while alternative treatments based of MgCl₂ [42] or CHF₂Cl [43] have been identified, cadmium chloride (CdCl₂) has long been established, and as such remains the research and industrial standard process. There a number of methodological variations in the manner of application but the principle remains the same; the free CdTe "back surface" is coated with a thin layer of CdCl₂, typically deposited via either thermal evaporation [44] or from a solution via spray or drop casting [45]. The stack structure is then annealed somewhere in the 380–450°C temperature range, usually in an air or oxygen containing ambient [46] (although some oxygen free processes have been reported as successful [30]). Following this annealing the cell is typically rinsed in water to remove any excess CdCl₂ remaining on the surface prior to whatever contacting procedure is being applied while the practical application of the CdCl₂ treatment was quickly established, the understanding of what the CdCl₂ treatment was actually doing to the device has taken longer to develop and has changed in recent times. This is primarily due to the multifaceted nature of its influences being hard to disentangle. On a structural level it has been widely demonstrated to mediate recrystallization in the CdTe and CdS layers [47], the level of recrystallization being partly dependent upon the starting grain structure of the films. For CdTe films deposited by low temperature methods, such as thermal evaporation or sputtering, which have a small as-deposited grain structure, CdCl₂ treatment induces near-complete recrystallization of the film to a significantly larger final grain structure [48] (Fig. 10.6). For higher temperature methods such as CSS, the as-deposited grain structure is large and thus more thermodynamically stable meaning recrystallization is only seen at the near CdS interface region where the grain structure is smaller and more defective [49]. Another standard result has been to observe an increase in carrier concentration following chloride treatment [42]. This has been widely attributed to the formation of the chlorine A-center V _Cd-Cl _i while the chloride treatment does undoubtedly have an effect on the doping level seen in measured devices, more recent work suggests its primary role may be to pacify grain boundaries. It has been demonstrated via high-resolution electron microscopy that the incorporated chlorine is predominately located at the grain boundaries, with their being little incorporated in the grain interiors [50]. This in turn has been shown to have a pronounced effect on the grain boundaries electrical behavior when analyzed by techniques such as EBIC [50]. Hence it may be considered that the process is in effect a passivation treatment rather than a doping step. There have also been suggestions that the chloride treatment may have inherent limits and that alternative processes need to be developed to overcome the current voltage limited performance of the technology (Section 10.3.2).

Figure 10.6. Structure of CdTe films before/after CdCl₂ treatment for different deposition temperatures.

(A) Low temperature CdTe, as-deposited, (B) Low temperature CdTe, after CdCl₂ treatment at 440°C, (C) High temperature CdTe, as-deposited, (D) High temperature CdTe, after CdCl₂ treatment at 400°C [51].

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Energy Management

Ibrahim Dincer , ... Maan Al-Zareer , in Comprehensive Energy Systems, 2018

5.5.8.2.2 Integrated systems

The efficiency of integrated or combined technologies (e.g., cogeneration) can be evaluated and compared by examining the depletion numbers D _p for the separate and combined technologies (see Fig. 18).

Fig. 18. Input and output exergy rates for separate and combined technologies to produce two products.

The consumption of nonrenewable energy resources corresponds to lower depletion numbers (see Eq. (2)). Consequently, the depletion number for an advanced combined technology $D_{\mathrm{p}}^{(\mathrm{comb})}$ should be lower than the weighted sum of the depletion numbers $D_{\mathrm{p}}^{(\mathrm{sep})}$ for the separate technologies. For the system in Fig. 18, $D_{\mathrm{p}}^{(\mathrm{sep})}$ is expressible as follows:

(4) $D_{\mathrm{p}}^{(\mathrm{sep})}=\frac{{\dot{\mathrm{E}}x}_{\mathrm{p}1}^{\mathrm{comb}}}{{\dot{\mathrm{E}}x}_{\mathrm{p}1}^{\mathrm{comb}}+{\dot{\mathrm{E}}x}_{\mathrm{p}2}^{\mathrm{comb}}}{D}_{\mathrm{p}}^{(1)}+\frac{{\dot{\mathrm{E}}x}_{\mathrm{p}2}^{\mathrm{comb}}}{{\dot{\mathrm{E}}x}_{\mathrm{p}1}^{\mathrm{comb}}+{\dot{\mathrm{E}}x}_{\mathrm{p}2}^{\mathrm{comb}}}{D}_{\mathrm{p}}^{(2)}$

where $D_{\mathrm{p}}^{(1)}$ and $D_{\mathrm{p}}^{(2)}$ are depletion numbers for two separate technologies and ${\dot{\mathrm{E}}x}_{\mathrm{p}1}^{\mathrm{comb}}$ and ${\dot{\mathrm{E}}x}_{\mathrm{p}2}^{\mathrm{comb}}$ are the rates of output exergy flows for products 1 and 2, respectively.

Illustrative Example

The principles discussed in this chapter are demonstrated for a combined gas turbine cycle with a hydrogen generation unit [32]. This design includes two important technologies: a solid oxide fuel cell (SOFC) with internal natural gas reforming and a membrane reactor (MR), and their combination with a hydrogen generation unit.

A common feature of SOFCs and MRs is their utilization of high-temperature oxygen ion-conductive membranes. Such membranes are conductive to negatively charged ions of oxygen and permit the separation of oxygen from air. This property accounts for their application as an electrolyte in SOFCs, where the chemical exergy of methane, through an intermediate stage involving its conversion to hydrogen and carbon monoxide and electrochemical oxidation with oxygen, is transformed into electrical work. In a MR, the membrane conducts both oxygen ions and electrons in opposite directions; such membranes are consequently often called mixed conducting membranes. In the present case, electrical work is not generated, but oxygen is separated from air and fuel combustion proceeds in an atmosphere of oxygen.

Oxygen ion-conductive membranes are made of ceramic materials (usually zirconia oxides) and have good performance characteristics at temperatures higher than 700°C. An SOFC stack is often introduced into traditional power generation cycles, where it operates at temperatures of 800–1100°C. A MR is being developed for operation up to 1250°C, as a substitute for combustion chambers in advanced zero-emission power plants. New materials for the anodes of SOFCs contain a catalyst for the methane reforming process, allowing methane conversion into a mixture of hydrogen and carbon monoxide directly on the surface of the anode [33]. SOFCs thereby become more flexible, compact, and effective, and avoid the need for preliminary reforming of methane.

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Natural Gas Conversion V

E.P. Foster , ... D.L. Bennett , in Studies in Surface Science and Catalysis, 1998

INTRODUCTION

Conventional technology options may lead to commercially viable gas-to-liquids (GTL) projects which are very large, have favorable site specific factors or very low natural gas costs. New and lower cost technology will be required to enable GTL to be broadly useful for remote gas monetization as a liquid fuel. Air Products and Chemicals, Inc. is currently developing two separate technologies which would result in a significant reduction in the capital investment required for GTL product plants. ITM Syngas is one of Air Products proprietary syngas technologies. It is in the early stages of development, but has the potential for very significant reductions in the cost of syngas, an important intermediate for GTL production. Air Products, along with its partners, have recently been selected by the U.S. Department of Energy (DOE) for an $85MM, three phase program to develop this ITM Syngas technology. The program will take eight years and culminate in a 15,000,000 SCFD pre-commercial syngas demonstration plant. In addition to ITM Syngas, in April 1997 Air Products started up a commercial scale Liquid Phase Methanol (LPMEOH) plant which converts coal derived syngas to methanol using a slurry bubble column reactor. This technology is expected to reduce the cost of liquid synthesis. It also produces an environmentally superior alternative fuel and/or chemical feedstocks.

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