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Proper functions problems

The proper functioning of the disks and drums is possible only over a narrow range of the liquid content of the agglomerating charge, and very little flexibility is available in this respect. This limitation may lead to operational problems as, for instance, when the balling feed is iron ore concentrates from a filter press and is excessively moist. [Pg.61]

Damages to human health and the environment are by economists most often considered as market failures since they are external costs not included in the price when a transaction is taking place on the market. If the damage were to be fully financially compensated in the transaction, the damage would not be an external cost and the market would function properly. A properly functioning market implies that there is no problem to be solved (from the point of view of an economist). Externalities is the term used by economists when exploring non-priced effects of transactions [6]. [Pg.111]

Outer membrane proteins face several problems. They have to cross the inner membrane thus implying that they are not allowed to contain hydrophobic membrane anchor or stop transfer sequences. Moreover, correct targeting to and stable insertion into the outer membrane is important for proper functioning. A number of OM proteins assemble into oligomers even prior to insertion. [Pg.278]

The main problem, the height-dependent differential pressure between the catho-lyte gap and oxygen across the ODC, could be solved with the pressure compensation system based on oxygen supply via gas pockets [1] (see Fig. 4.2). The first successful piloting was done in October 1995 on the basis of Bayer engineering and construction. In a four-gas-pocket element with each electrode segment of 180 x 180 mm2 individually supplied with power, the proper function of pressure compensation could be proven for a total height of 90 cm. [Pg.63]

Accdg to the paper of 1962 by Macek (Ref 14) "The shift of attention to the problem of transition to detonation in solid explosives, about a decade ago, was occasioned by the awareness that the problem may be pertinent to the proper functioning of large rocket propellant grains, and was given additional impetus by the scientific approach to shock initiation. From initial qualitative suggestions of Kistiakowsky (Refs 4 6) and Ubbelohde (Ref 5) there developed the hypothesis of precursor shock, which postulates a sequence of events rather analo-... [Pg.479]

Coenzymes The pyruvate dehydrogenase complex contains five coenzymes that act as carriers or oxidants for the intermediates of the reactions shown in Figure 9.3. Ei requires thiamine pyrophosphate, Ep requires lipoic acid and coenzyme A, and E3 requires FAD and NAD+. [Note Deficiencies of thiamine or niacin can cause serious central nervous system problems. This is because brain cells are unable to produce sufficient ATP (via the TCA cycle) for proper function if pyruvate dehydrogenase is inactive.]... [Pg.108]

Any governing model equations have to be supplemented by initial and boundary conditions, all together called side conditions. Their definition means imposing certain conditions on the dependent variable and/or functions of it (e.g. its derivative) on the boundary (in time and space) for uniqueness of solution. A proper choice of side conditions is crucial and usually represents a significant portion of the computational effort. Simply speaking, boundary conditions are the mathematical description of the different situations that occur at the boundary of the chosen domain that produce different results within the same physical system (same governing equations). A proper and accurate specification of the boundary conditions is necessary to produce relevant results from the calculation. Once the mathematical expressions of all boundary conditions are defined the so-called properly-posed problem is reached. Moreover, it must be noted that in fuel cell modeling there are various... [Pg.76]

Typical functions of the middle layer are anti-reset windup, variable structure elements, selectors, etc. Although essential for the proper functioning of any practical control system, they have been completely neglected in research circles. We have yet to find an effective multivariable anti-reset windup scheme that works on all our test cases. Can all, or at least most, industrial control problems be solved satisfactorily with some simple loops and minimum-maximum selectors How can the appropriate logic structure be designed How should the loops be tuned to work smoothly in conjunction with the logic How can one detect deteriorating valves and sensors from on-line measurements before these control elements have failed entirely ... [Pg.533]

The work on biomimetic models for [NiFe] and [FeFe] hydrogenase has been described in several review articles [15b 158]. In this work, many of the structural features important for proper function found in the native systems have been successfully incorporated for example, the bimetallic Ni-Fe or Fe-Fe core with rather short metal-metal distances and an open coordination site at one metal, the sulfur-rich environment (terminal and bridging thiolate ligands), CO/CN ligation of the iron(s), and the incorporation of a base for acceptance of the proton and, more recently, of hydride bridges. Still-existing problems of many model systems are the O2 sensitivity, the high overpotentials, and lack of activity (low turnover rates). [Pg.212]

FLC system approach can be used to solve problems. Many applications of FLC are related to simple control algorithms such as the PID controller. In a natural way, nonlinearities and exceptions are included which are difficult to realize when using conventional controllers. In conventional control, many additional measures have to be included for the proper functioning of the controller anti-resist windup, proportional action, retarded integral action, etc. These enhancements of the simple PID controller are based on long-lasting experience and the interface of continuous control and discrete control. The fuzzy PID-like controller provides a natural way to applied controls. The fuzzy controller is described as a nonlinear mapping. [Pg.175]

Article VI, which deals with the verification of legitimate activities in the chemical industry through declarations, inspections and transfer controls, has nevertheless an important role to play. It increases confidence in the legitimacy of their activities, and at the same time can highlight possible problem areas in the proper functioning of national control systems for chemicals. [Pg.33]

An imbalance in mineral component economy leads to disturbances in cell functions and the appearance of disease symptoms. The human-transformed natural environment usually deteriorates and exerts a negative influence on our health and food quality. The presence and availability of some mineral elements vital for the proper functioning of the human body are particularly vulnerable to such adverse changes. Diet and the chemical elements in food can affect the risk of contracting diseases to various extents. An inappropriate diet is a factor favouring the development of circulatory diseases and carcinomas [3] (the main causes of premature death) and has become a serious social and economic problem. [Pg.203]

Problem Concern for the proper functioning of the contractor s project... [Pg.230]

In general, research workers are concerned with the theoretical aspects of their particular problems rather than with the details of the design and proper functioning of the apparatus required to help them solve the problems. [Pg.87]

The second method, that of Heitler and London, takes account of this by starting from the assumption that, at least for the molecular state in which the energy is least, both electrons are never to belong to the same atom. If in addition we take account of the exclusion principle (here the spift must be considered), the method may be simply described as an attempt to represent the actual proper functions of the problem approximately by the following functions, which are antisymmetric in the electrons ... [Pg.65]

The treatment of UTIs in horses consists of proper antimicrobial therapy and, if possible, the correction of the predisposing anatomical or functional problems with urine flow (e.g. outflow... [Pg.172]

Iodine is an essential micronutrient in animals and humans, necessary for the production of thyroid hormones and for the proper functioning of the thyroid gland, and deflciencies can lead to severe metaboflc disorders. As reported by the World Health Organization in 1999, iodine deflciency is a significant public health problem in 130 countries, with one-third of the worlds population estimated to be at risk. Furthermore, because radioactive iodine is concentrated in the human thyroid (VanMiddlesworth et ai, 2000), an uncontrolled release of radioactive iodine could constitute a direct threat to human populations. [Pg.93]

Ans. Yes. The error in replication is not a problem since many correct copies (99,999 out of each 100,000) of the mRNA and polypeptide will be produced and this is sufficient for the proper functioning of the cell. The one incorrect (out of 100,000) copy of the mRNA and polypeptide will not be used by the cell. Furthermore, the error is not propagated to subsequent generations of cells or to offspring. A much higher accuracy is needed for replication because errors accumulate and are transmitted to subsequent generations of cells and offspring. [Pg.449]

McLEAN Do I understand you to suggest that the fish toxicity problem arises from the formation of polymeric particulate aluminates which interfere with the proper function of the gills. [Pg.365]


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