Nonchemical methods

Gravity override of low density steam leads to poor volumetric sweep efficiency and low oil recovery in steam floods. Nonchemical methods of improving steam volumetric sweep efficiency include completing the injection well so steam is only injected in the lower part of the oil-bearing zone (181), alternating the injection of water and steam (182), and horizontal steam injection wells (183,184). Surfactants frequently are used as steam mobihty control agents to reduce gravity override (185). Field-proven surfactants include alpha-olefin sulfonates (AOS), alkyltoluene sulfonates, and neutralized... 

Efficiency of the cross-linking reaction can be defined as the ratio of effective cross-link density, px, to the theoretical cross-link density, p(. Theoretical cross-link density assumes that all of the cross-linker added to the formulation created elastically effective cross-links however, it cannot be defined for nonchemical methods. Thus the theoretical cross-link density, p is given as... 

The importance of biopolymer deposition on the membrane has been highlighted by Chu and Li [34] who noted that such material may accelerate bacterial attachment to the membrane in addition to its contribution to fouling resistance. The formation of a slime layer on the membrane, comprising an EPS matrix with embedded bacteria, may be analogous to a biofilm, the significance of which is the difficulty of its removal by nonchemical methods. The question of whether biofilm formation plays a significant role in MBRs is yet to be addressed. Indeed, a comprehensive model of fouling in MBRs is not yet available. 

Perhaps there are better methods than chemicals for controlling aquatic weeds. So far few have been identified or developed. Although biological and other nonchemical methods are receiving greater emphasis in current research, the gravity of the weed problem and the lack of other... 

A brief discussion of research trends in the field of plant disease control will be helpful in the consideration of recent developments in nonchemical methods of disease control. 

Physical disturbances (including loud noises, microwaves, and high-intensity light) and substances capable of causing intense sensory stimulation are among the nonchemical methods explored to impair performance. 

As in the case of hydrogels, SELP-47K films have been demonstrated to be extremely biocompatible while allowing cell proliferation [65]. This biocompatible feature, together with mechanical properties, allows SELPs to be explored for several applications, namely contact lenses, synthetic corneas, intraocular lenses, ophthalmic drug delivery matrices, and so on. Although methanol is routinely used to render aqueous insolubility as well as to improve the mechanical properties, autoclaving has been shown to stabilize electrospun nanoflbres and therefore can be an alternative nonchemical method for the stabilization of the film stmcture. 

There are two scenarios under which is possible the approval of an active substance that fails the cutoff criteria if the exposure to humans, under realistic proposed conditions of use, is negligible (see Annex 11, point 3 of Regulation (EC) No. 1107/2009 for more details) and if it is necessary to control a serious danger to plant health, which cannot be contained by other available means, including nonchemical methods (see Article 4, point 7 of Regulation (EC) No. 1107/2009 for more details). 

Another special group for active substances is that of candidates for substitution and recognized in Article 24 of Regulation (EC) No. 1107/2009. Active substances, which meet one or more of the additional criteria laid down in point 4 of Annex 11, will be only approved for seven years. Furthermore, any pesticide containing that active substance will be required to undergo comparative assessment at member state-level (see Article 50 of Regulation (EC) No. 1107/2009 for more details), comparing this pesticide with other approved ones or nonchemical methods of control/preventiOTi to substitute the more hazardous with the safer optimi [1]. 

Nonchemical methods are preferred if they provide satisfactory pest control... 

Sustainable biological, physical, and other nonchemical methods... 

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