硼砂水溶液是一种重要的标准缓冲溶液。请说明其为何具有酸碱缓冲溶液的性质,并计算其pH

题型:问答题

问题:

硼砂水溶液是一种重要的标准缓冲溶液。请说明其为何具有酸碱缓冲溶液的性质,并计算其pH。已知:

考点:普通考研农学联考农学硕士联考化学
题型:问答题

食盐可以用来作饮料。 [ ]

题型:问答题

2012年11月,中国白酒行业遭遇了塑化剂风波。DBP(化学式为C16H22O4)和DEHP(化学式为C24H38O4)是两种常见的塑化剂,下列关于它们的说法正确的是

A.DBP中有42个原子

B.DBP和DEHP均由C、H、O元素组成

C.DBP的相对分子质量是278

D.DBP和DEHP中O元素质量分数相同

题型:问答题

“我们必须清醒认识到,我国仍处于并将长期处于社会主义初级阶段的基本国情没有变……”,我国开始进入社会主义初级阶段的标志是

A.新中国成立

B.三大改造完成

C.“ * * ”结束

D.实行改革开放

题型:问答题

Joe Harberg became an energy-efficiency guru because he didn’t know the first thing about energy efficiency. In 2003 he was constructing a new home in Dallas and wanted to work with his builder to make the place as environmentally friendly as possible. But neither Harberg nor his designer had any training in how to turn an ordinary house green, and they found few resources to help them. "It was so frustrating," says Harberg, 46, a Dallas-based entrepreneur.
Relying principally on the Internet, Harberg—who previously had worked as a marketing expert and real estate developer—did manage to build an energy-efficient home. He boasts that his electricity bills are regularly 50% less than those of similar homes in his neighborhood, and the entrepreneur in him saw an opportunity. Lots of people worry about global warming, not to mention the soaring costs of powering a home, but they don’t know what to do about it. Working with his brother-in-law Josh Stern, Harberg helped launch what would become Current Energy, in 2005, to provide the needed expertise. "We aspire to be the ones who put it all together for you," Harberg says.
Today Current Energy operates what is probably the first dedicated energy-efficiency retail store in the U. S., a hip space in Callas’ tony Highland Park where shoppers can buy ultraefficient air conditioners, tankless water heaters and even electric votive candles. But while the store itself is green cool—reminiscent of the Apple retail shops that Harberg helped roll out in his previous career—the real value in Current Energy isn’t in its gadgets but in the service it offers. "It’s an art to figure out how to save money at home," Harberg says. "We do the work. "
Homeowners who come to Current Energy can order an energy audit—a socket-to-faucet analysis of how to eliminate energy and water waste. After receiving the report, customers can follow as many of the recommendations as they wish, with Current Energy employees involved in the installation work—down to changing the lightbulbs. Joseph Van Blargan, a writer, secured an assessment for his Dallas home and estimates that the upgrades save him about 30% on his monthly energy bill. "I could have done it on my own, but there would have been bits and parts I would have missed," he says.

Joe’s Green Shopping List


At its retail location and online, Current Energy sells a wide range of energy-efficiency gadgets:
1) Digital PowerCost Monitor provides real-time data on your energy consumption, $185
2) Magic Globe, a solar-powered light, $ 50
3) Solio Solar Charger is a way to power all those electronic devices with the sun, $ 99
4) Solar Backpack lets you carry your laptop—and charge it for free, $140
5) Kill A watt Electricity Meter monitors the power use and cost of any appliance, $40
Greenies who live outside Dallas will soon be able to get an energy assessment from currentenergy, com, and the company will work with licensed auditors in your town to carry out the improvements.
What Current Energy does isn’t as easy as it looks. Maximizing the efficiency in your home means more than jut chucking your incandescent lightbulbs. You might improve your attic insulation to prevent the loss of heat in the winter, but go overboard, and you could end up choking on indoor air pollution. Just as a house is more than four walls and a door, energy efficiency should be holistic, with insulation, appliances, lighting and clean electricity all working together.
That’s a message the tireless Harberg—who could probably power Texas Stadium if you plugged him into the grid—spreads with zeal. He hosts a weekly radio call-in show and was recently on the TV show Good Morning Texas touting the benefits of an indoor air-quality monitor. "You’re saving people money and saving the earth at the same time," he says excitedly. As business plans go, that’s an awfully good one.

Why does the passage say that "What Current Energy does isn’t as easy as it looks."

题型:问答题

没有内毒素的部位,微循环及毛细血管通透性正常,怎样刮也不会出痧。()

更多题库