The actual concentration need not be large for a substance to be a pollutant; in fact the numerical value tells us little until we know how much of an increase this represents over the concentration that would occur naturally in the area. For example, sulfur dioxide has detectable health ...
The plant they settled on was Devil's vine, 38 because of its toughness. With the help of a bacterium they were able to ferry the rabbit version of the gene into the plant's chromosomes(染色体) and thus to engineer a type of Devil's vine able to produce an air-cleaning substance. ...
The volatile air processing chemical substance is arranged inside the pore. The small diameter particle of the base substance one end, desirably, in order to gather in the end which it adjoins to the nose which projects, it can provide grain size and the pore. This structure, directing the...
The no good bits: the script is not very convincing, lacks substance; both female and male leads' unrealistic makeup just doesn't seem truthful to the characters; lead performances are cringy at times; pacing seems a bit off especially towards the end.Overall it's a very forgettable movie...
However, economic globalization must undergo adjustments in both form and substance. It should be made more open, inclusive, balanced and beneficial to all. China has not only benefited from economic globalization but also contributed to it. As an active participant in economic globalization, China...
1我想知道matter与substance在化学上意思的区别,我的书里面有这么几句"The world around us is made up of matter.Matter is anything that occupies space and has mass.Everthingwe see,touch,taste,or smell is matter.""One particular type of matter is called a substance .Iron,water and air are exam...
by air / bicycle / boat / bus / car / letter / post / plane / telephone /train / wire 6. at daybreak / sunrise / dawn / noon/ dark / night 7. out of breath / control / question / sight 8. in fact / reality / substance / nature / practice / theory / short / brief ...
The HSE terms these limits Workplace Exposure Limits (WELs) and they are defined as the maximum concentration of a hazardous airborne substance that a worker may be exposed to over a defined period such as an 8-hour shift. WELs apply to anybody working within an environment where hazardous s...
One of the most promising replacements is a substance called PHA, or polyhydroxyalkanoate, a type of bio-polyester made by bacterial fermentation of sugars and lipids. “We’d love to see an all-PHA future,” NREL’s Knauer says, in part because the plastic can degrade into nontoxic c...
A drug is a chemical substance. 2015年12月四级真题(第二套)听力 Section C A drug user is the person who takes the drug. 2015年12月四级真题(第二套)听力 Section C A dry mouth may reduce taste sensitivity, but taste is restored by drinking fluids. 2019年12月四级真题(第三套)阅读 Section...