The present economy remains dependent on a massive inward flow of

游客2025-02-22 22

问题          The present economy remains dependent on a massive inward flow of
   natural resources that includes vast amounts of non-renewable resources,
   followed by a reverse flow of economically spent matter back to the ecosphere.
Line    Chemical sustainability problems are determined largely by these economy-
(5)    ecosphere material flows which current chemistry education essentially ignores,
   such that it has become imperative for chemists to develop the technological
   dimension of a sustainable civilization.  Chemistry teachers should better
   emphasize the effect of compositions, outcomes, and economics of chemical
   processes on both human health and the ecosphere. There is one overarching
(10)    scientific reason why chemical technology pollutes: chemists developing new
   processes strive principally to achieve reactions through relatively simple
   reagent designs by employing almost the entire periodic table to attain diverse
   reactivity, while by contrast nature accomplishes a huge range of selective
   biochemical processes through a reagent design much more elaborate than the
(15)    aforementioned synthetic ones. Electric eels can store charge via concentration
   gradients of biochemically common alkali metal ions across the membranes of
   electroplaque cells, while synthetically-designed batteries used for storing
   charges must make use of elements such as lead and cadmium. Given this
   strategic difference, manmade technologies often distribute throughout the
(20)    environment persistent pollutants that are toxic because they contain elements
   that are used sparingly or not at all in biochemistry.
         Imagine all of Earth’s chemistry as a mail sorter’s wall of letter slots in a
   post office, with the network of compartments extending toward infinity, each
   of which representing a separate chemistry so that, for example, thousands of
(25)    compartments are associated with stratospheric chemistry or with a human cell.
   An environmentally mobile persistent pollutant can move from compartment to
   compartment, sampling a large number and finding those it can perturb, and
   while many of these perturbations may be inconsequential, others can cause
   unforeseen catastrophes, such as ozone holes or endocrine disruption in the
(30)    human body. Most compartments remain unidentified, furthermore, giving
   ample reason for scientific humility when considering the safety of persistent
   mobile compounds.
         There are several obstacles to overcome in achieving a sustainable
   chemistry free of these mobile pollutants, the first being that of incorporating
(35)    environmental considerations into decisions concerning the reactions and
   technologies to be developed in the laboratory. It is equally critical that
   chemistry that is not really green does not get sold as such, and that the public
   is not misled with false or insufficient safety information. And since many
   chemical sustainability goals such as those associated with solar energy
(40)    conversion call for ambitious, highly creative research approaches, short-term
   and myopic thinking must be avoided-after all, chemistry exerts a near
   boundless influence on human action and is thus inextricably intertwined with ethics. [br] Which of the following best describes the organization of the first two paragraphs of the passage?

选项 A、An argument is made, then complicated through the admission of the argument’s limitation.
B、The general nature of a problem is presented, followed a concrete example of the problem.
C、A thesis is stated, and evidence is provided along with an analysis to support the thesis.
D、The method of research in a field of science is explained, than illustrated through a specific case.
E、Two opposing methods of the best means to perform a science are explained, then shown to reconcilable.

答案 B

解析

转载请注明原文地址:http://tihaiku.com/zcyy/3967696.html

相关试题推荐

随机试题

最新回复(0)

The present economy remains dependent on a massive inward flow of

A、The"slingeffect"remainsunprovenandrequiresexperimentalcorroboration.B

FIASCO:A、anunanticipatedprogressionB、apowerfulpresentimentC、amollifyings

Atthepresenttime,unfortunately,severalgovernmentsgrantpermissiontorapa