The passage implies that cellulose is a very porous substance because it contains______.A.a substance that creates pressureB.millions of tiny holesC.a substance that dissolves itD.liquid medicine
The passage implies that cellulose is a very porous substance because it contains______.
A.a substance that creates pressure
B.millions of tiny holes
C.a substance that dissolves it
D.liquid medicine
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Substance Dependence refers to a maladaptive pattern of substance use leading to clinically significant impairment or distress characterized by things like () A、toleranceB、spending lots of time in activities to obtain the substanceC、withdrawD、Taking the substance in larger amount than before
Part ADirections: Read the following three texts. Answer the questions on each text by choosing A, B, C or D. Mark your answers on ANSWER SHEET 1.Medicine comes in many forms. In its liquid form, medicine affects the body very quickly. But the effects of liquid medicine arch' t usually long-lasting. This is why pills and capsules (胶囊) are also used.The pills and capsules being sold today arch' t perfect, either. Pills dissolve in the stomach. The medicine in the pills is released when the pills dissolve. But often, the pills dissolve too quickly.Scientists have been trying to develop a pill that can release medicine slowly over a long period of time. They have applied their knowledge of plants to produce the "osmotic (渗透的) pump pill".The cell walls of plants are made of cellulose (纤维素). Cellulose is a very porous substance. Their holes are big enough to allow water through the cell walls. As water enters a cell, pressure builds up in the cell. The pressure pumps other substances out of the cell. These substances leave the cell through the cellulose wall. This slow, steady process is called osmosis.The osmotic pump pill is coated with synthetic cellulose. Liquid medicine is contained in the pill. The holes in the cellulose coating of the pill are big enough to allow water in the pill. As water from the body enters the pill, pressure builds up in the pill. The medicine is then slowly pumped out of the pill.The passage implies that the osmotic pump pill is better than other pills and capsules because______.A.it releases medicine slowly over a long period of timeB.it helps to build pressure in the bodyC.the medicine in the pill can affect the body quicklyD.the coating doesn't dissolve in the stomach
The passage implies that medicine in an osmotic pump pill will leave the pill when ______.A.the pill is swallowedB.the medicine is dissolved with water from the bodyC.enough pressure builds up in the pillD.the cellulose coating is dissolved
______should be involved in the campaign to deal with substance abuse among youth.A. SchoolsB. Local, state and national governmentsC. Families and communityD. All of the above
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They use special chemical substance to _________ the growth of crops.A aggravateB accelerateC strengthenD reinforce
Every one of us () that when any substance burns, it unites with oxygen. A、knowB、knowsC、have knownD、has known
The biological sewage treatment plant utilizes Oto completely break down the sewage into an acceptable substance for discharge-into anywaters A.agitation functionB.bacteriaC.chemicaD.oxidizing function
The sum of the sensible heat and the latent heat of any substance is known as ______.A.total heatB.residual heatC.specific heatD.superheat
Which substance is NOT considered to be Oil under the pollution prevention regulations?A.Petroleum and fuel oilB.SludgeC.Oil mixed with dredge spoilD.Oil refuse and oil mixed with wastes
Spontaneous combustion is caused by ______.A.An outside heat source heating a substance until it ignitesB.Conduction of heat through a wall of material to the substanceC.Chemical action within a substanceD.All of the above
Which statement is TRUE concerning the flash point of a substance ________.A.It is lower than the ignition temperatureB.It is the temperature at which a substance will spontaneously igniteC.It is the temperature at which a substance,when ignited,will continue to burnD.It is the temperature at which the released vapors will fall within the explosive range
Which substance might be subject to spontaneous combustion ________.A.CoalB.Scrap rubberC.LeatherD.All of the above
The lowest temperature required to cause self-sustained combustion of a substance independent of any outside source of ignition is called ______.A.Explosive rangeB.Flash pointC.Ignition temperatureD.Combustion temperature
Which molten substance is poured into the basket of a wire rope socket being fitted to the end of a wire rope ________.A.BabbittB.BronzeC.LeadD.Zinc
Walnut trees __________ environment stresses such as drought by producing significant amountsof a substance similar to aspirin.A.turn toB.confirm toC.contribute toD.respond to
The author gives substance to the passage through the use of___________.A.interviews with authorities in the field of water controlsB.opinion and personal observationsC.definitions which clarify important termsD.strong argument and persuasion
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单选题Which condition is necessary for a substance to burn?()AThe temperature of the substance must be equal to or above its fire pointBThe air must contain oxygen in sufficient quantityCThe mixture of vapors with air must be within the explosive rangeDAll of the above
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