时间:2019年12月11日 16:06:07

Usually when we think of moldy foods, we picture a month-old loaf of b forgotten in the back of a refrigerator. But some moldy foods can be quite delicious. For instance, many cheeses owe their sharp flavor to molds. The making of any cheese is essentially a process of limited, controlled spoilage.通常,我们一想到发霉的食物时,脑海中会浮现出一条遗忘在冰箱后面一个月的面包的画面。然而有些发霉的食物是相当美味的。例如,许多奶酪发霉之后就有一种独特的风味。任何奶酪的制作工艺实际就是一种有限的,可控制的发酵过程。In effect, a mold partly digests, or rots the cheese. The molds used to ripen cheese are not the molds that would naturally develop on the cheese over time, but are specially-produced molds. During the process of aging any mold-ripened cheese, fats and proteins are broken down into strong smelling molecules. These molecules give mold-ripened cheese its particularly strong odor and taste. A bluish-green mold helps ripen blue cheese, giving it its name, aroma and color.实际上,霉菌会一定程度上吞噬或者腐蚀着奶酪。把奶酪催熟的霉菌并不是奶酪自然生长一段时间所产生的,而是一种特制的霉菌。在霉菌催熟奶酪的过程中,脂肪和蛋白质经分解释放强烈气味的分子。这些分子使催熟的奶酪具有特殊而又强烈的气味与芬芳,而蓝青色的斑点霉菌则从外观上给予蓝色熟奶酪以颜色,气味和名称。In order to age blue cheese, a cheese maker injects the mold into the cheese. Cheeses like blue cheese that are ripened from within are frequently washed or brushed to remove undesirable microorganisms which might interfere with the activity of the ripening mold inside. While blue cheese is mold-ripened from the inside, soft, pungent cheeses like Camembert and Brie are ripened from the outside with a coat of a white mold whose enzymes slowly penetrate the cheese and transform it from a chalky, bland solid, into the custard-like, creamy treat cheese fanciers love.为催熟蓝色奶酪,奶酪专家会向奶酪里添加催熟霉菌。蓝色奶酪等催熟奶酪则通过频繁洗刷,去除干扰催熟霉菌活动的多余微生物。与蓝色奶酪从里向外催熟的原理不同,向来以柔软、芳香著称的法国卡曼波特奶酪和布里白奶酪都是由外及里催熟的,表面的一层白霉菌会慢慢的将其中的化学酶渗入奶酪,并把白色无味的固体转变成人们喜爱的蛋糊乳状。Of course, eating most moldy foods is not a good idea, but eating cheese that has ripened due to a special molding process can be a delectable experience.当然,吃很多发霉的食物不是什么好事,但是吃那些在特殊霉变过程中变熟的奶酪会是一个很享受的体验。201306/242900

Science and technology科学技术Pilotless aircraft无人驾驶飞机This is your ground pilot speaking呼叫,这里是你的地面飞行员Autonomous civil aircraft could be flying before cars go driverless民用飞机会先于汽车实现无人驾驶WITHIN the next few weeks a twin-engined Jetstream will take off from Warton Aerodrome in Lancashire, England, and head north towards Scotland.在接下来的几周里,一架双引擎飞机喷流将会从英格兰兰开夏郡的沃顿机场起飞,向北飞往苏格兰。Like any other flight, the small commuter airliner will respond to instructions from air-traffic controllers, navigate a path and take care to avoid other aircraft.与其他班机一样,这架小型通勤客机将会根据空中交通管制员的指示,沿着一条航路飞行,注意避开其他飞机。But the pilot flying the aircraft will not be in the cockpit: he will have his feet firmly on the ground in a control room back at Warton.但是驾驶这架飞机的飞行员却没在驾驶舱里:他在沃顿机场的一个控制室里驾驶着飞机,双脚仍然稳稳地踩在地面上。Pilotless aircraft are now widely used by the armed forces, but those drones fly only in restricted airspace and conflict zones.无人机现在已广泛应用于军队之中,但这些无人机仅用于在禁飞区及冲突地区。The Jetstream mission is part of a project to develop the technologies and procedures that will allow large commercial aircraft to operate routinely and safely without pilots in the same skies as manned civilian flights.而喷流的任务是某个技术及程序开发项目的一部分,该项目的目的在于能让大型商用飞机在没有飞行员的情况下安全的进行常规飞行,与有人驾驶的民航班机在同一片天空中飞行。Fasten your seat belts系紧您的安全带To reassure those of a nervous disposition, the test flights do not carry passengers and pilots remain in the cockpit just in case things go wrong.为了让那些神经质的人安心,测试的飞机不会有乘客,驾驶舱中仍然有驾驶员以防万一,In that way they are similar to Google’s trials of driverless cars, which have drivers inside them to take over if necessary while on public roads.这有点类似于谷歌无人驾驶汽车的实验,在公路上行驶时,如有必要,车中的驾驶员可以控制汽车。Yet unmanned commercial aircraft are likely to enter service before people can buy autonomous cars.但是无人驾驶的商用飞机很可能在人们可以买到无人驾驶汽车前便能投入使用。Modern aircraft are aly perfectly capable of automatically taking off, flying to a destination and landing.现代的飞机已经完全有能力进行自动起飞,自动飞往目的地,自动着陆。These tests are trying to establish whether they can do those things safely without a pilot in the cockpit and at the same time comply with the rules of the air.而要进行的测试是想确认在驾驶舱没有飞行员的情况下,飞机能否在遵守飞行规则的同时,还能安全的完成以上三件事情。Progress is being made, a conference in London heard this week.笔者本周从在伦敦召开的一次会议上获悉,事情正在取得进展。It was organised by the Autonomous Systems Technology Related Airborne Evaluation and Assessment, the group staging the British test flights.本次会议是由机载无人系统技术评审组织举办的,就是该组织在英国进行了无人机测试。This 62m programme, backed by the British government, involves seven European aerospace companies:该项目获得了英国政府的持,投资达六千两百万英镑,共有七家欧洲的航空工业公司参与其中:AOS, BAE Systems, Cassidian, Cobham, QinetiQ, Rolls-Royce and Thales.机载观测系统公司,英国宇航系统公司,凯西典公司, 科巴姆公司,奎奈蒂克公司,劳特莱斯公司及泰雷兹公司。It is potentially a huge new market.这是一个潜在的巨大新兴市场。America’s aviation regulators have been asked by Congress to integrate unmanned aircraft into the air-traffic control system as early as 2015.美国国会已要求该国的航空协调员要在2015年将无人驾驶飞机加入空中交通管制系统。Some small drones are aly used in commercial applications, such as aerial photography, but in most countries they are confined to flying within sight of their ground pilot, much like radio-controlled model aircraft.有些小型无人机已经应用于航拍等商业用途,但在大多数国家,小型无人机的飞行范围被限制在其地面飞行员的视野以内,很像无线电遥控的模型飞机。Bigger aircraft would be capable of flying farther and doing a lot more things.再大一点的无人机能够飞的更远一些,可以做更多的事情。Pilotless aircraft could carry out many jobs at a lower cost than manned aircraft and helicopters—tasks such as traffic monitoring, border patrols, police surveillance and checking power lines.无人驾驶飞机可以完成很多工作,并且比有人驾驶的飞机和直升机成本更低,比如说交通监测,边境巡逻,警务监视及电缆检查等任务。They could also operate in conditions that are dangerous for pilots, including monitoring forest fires or nuclear-power accidents.无人机还可以在对飞行员有危险的环境下工作,包括监视森林火灾或核电事故。And they could fly extended missions for search and rescue, environmental monitoring or even provide temporary airborne Wi-Fi and mobile-phone services.而且无人机还可以执行更多的任务,如搜索救援,环境监测,甚至提供临时的机载无线网络和移动电话务。Some analysts think the global civilian market for unmanned aircraft and services could be worth more than billion by 2020.有分析师认为,到2020年,无人驾驶飞机及其务的全球民用市场的价值可超过500亿美元。Whatever happens, pilots will still have a role in aviation, although not necessarily in the cockpit.无论发生什么,飞行员仍会在航空业占有一席之地,虽然不一定是在驾驶舱里。As far as the eye can see there will always be a pilot in command of an aircraft, says Lambert Dopping-Hepenstal, the director of ASTRAEA.在可以预见的未来,飞机一直都会由飞行员掌控, ASTRAEA的主任Lambert Dopping-Hepenstal说,But that pilot may be on the ground and he may be looking after more than one unmanned aircraft at the same time.但飞行员或许会留在地面上,有可能同时照看好几架无人机。Commercial flights carrying freight and express parcels might one day also lose their on-board pilots.运送货物和快递包裹的商用飞机某天也可能会失去其随机的飞行员。But would even the most penny-pinching cut-price airline be able to sell tickets to passengers on flights that have an empty cockpit?但就算廉价航空公司再怎么精打细算,它能把没有飞行员的飞机的机票卖出去吗?More realistically, those flights might have just one pilot in the future.更现实点说,未来的商用飞机可能只有一名飞行员。Technology has aly relieved the flight deck of a number of jobs.飞行班组的许多职位已经被技术取代了。Many early large aircraft had a crew of five: two pilots, a flight engineer, a navigator and a radio operator.许多早期的大型飞机上有五名机组成员:两名飞行员,一名飞行机师,一名领航员及一名无线电话务员。First the radio operator went, then the navigator, and by the time the jet era was well under way in the 1970s flight engineers began to disappear too.最先是无线电话务员消失了,然后是领航员,等到了20世纪70年代,进入喷气机时代后,飞行机师也消失了。Next it could be the co-pilot, replaced by the autonomous flight systems now being developed.下一个消失的会是副驾驶,被现在正在开发中的自主飞行系统取代。The flight over Scotland will test how well air-traffic controllers can communicate with the ground pilot through the aircraft.在那架飞往苏格兰的飞机上将会测试空中交通管制员通过飞机与其地面飞行员通话的质量。The project is also exploring ways to make the radio and satellite links secure and reliable.该项目还在探寻使无线电及卫星连接安全可靠的方法。But engineers still have to prepare for the eventuality that the link breaks; the aircraft then has to have enough autonomy to operate safely until communications are restored or it can land using its own guidance systems.但是工程师仍必须为连接中断的可能性做好准备;然后飞机必须要有足够的自主权来保飞行安全,直至通讯恢复正常,或者能够使用自己的导航系统着陆。Unmanned aircraft will, therefore, need a sense and avoid capability.因此无人驾驶飞机需要感应并规避的能力。This can be provided by transponders that bleep the aircraft’s presence to other aeroplanes and air-traffic controllers.异频雷达收发机便具备这一功能,它会发出哔哔声来提示其它飞机及空中交通管制员本飞机的存在。But not all manned aircraft have such kit.但并非所有的有人驾驶飞机都有该功能。Some light aircraft and gliders operating at low altitudes in clear weather are not required to have even radios, let alone transponders or radar.一些在晴朗天气下进行低空飞行的轻型飞机和滑翔机甚至不需要无线电,更别提异频雷达收发机或雷达了。Which is why pilots keep their eyes peeled when such traffic might be about.这也是为什么在可能发生这种情况时,飞行员要时刻保持警惕。ASTRAEA’s Jetstream, therefore, also uses cameras to allow the ground pilot to look around outside the cockpit.因此ASTRAEA的捷流号还使用了摄像头以便使地面飞行员可以查看驾驶舱外的情况。Image-recognition software can warn of other aircraft.影像识别软件可以在出现其它飞机时发出警告,This is being tested against different backgrounds, such as a cluttered landscape or a hazy sky.目前正在不同的环境下对该功能进行测试,如地形复杂或天空雾蒙蒙的环境。In other trials, different aircraft are being flown in the vicinity of the Jetstream, and some of them will be flown deliberately towards it on a potential collision course, to see if these intruding aircraft can be recognised by the automated systems and the appropriate avoiding action taken.在其它的试验中,不同的飞机飞至捷流附近,其中几架故意以可能与之相撞的航线飞向捷流,以测试自动系统能否识别这些入侵的飞机并采取适当的规避措施。These flights are taking place in an area cleared of other aircraft over the Irish Sea.以上飞行测试是在爱尔兰海上空一片没有其它飞机经过的空域进行的。The results to date suggest you can do sense-and-avoid as well as a human, says Mr Dopping-Hepenstal.迄今为止的测试结果表明系统的感应并规避的能力能做到和人一样, Dopping-Hepensta说。A pilotless plane must also be able to act autonomously in an emergency.在发生紧急状况时,无人机必须能够自行采取行动。In the event of an engine failure, for instance, it could use its navigational map to locate a suitable area to put down.比如,如果一台引擎发生故障,无人机需要使用其航行图来找到合适地点降落。But what if this was an open field that happened to be in use for, say, a fair?但如果其选择的空地恰好被占用了,比如说成了集市,怎么办?A forward-looking camera might show a ground pilot that.此时前视摄像头会将此影像传给地面飞行员。But if communications were lost the aircraft would rely on image-recognition software and an infra-red camera to detect the heat given off by people and machines and so decide to try to land elsewhere.但如果通讯中断,飞机将依靠影像识别软件及红外摄像头来感知人或机器发出的热量,以此来决定去其它地点降落。The ASTRAEA researchers are carrying out a lot of their work using flight simulators and air-traffic-control data.ASTRAEA的研究人员的许多工作都是通过飞行模拟装置及空中交通管制数据来完成的。But eventually they will still have to prove that their systems can work in the real world—even during emergency landings.但最终他们还是要明他们的系统要能应用在现实的世界里,甚至在紧急迫降时也能使用。In order to satisfy risk-averse aviation regulators, the researchers are working with Britain’s Civil Aviation Authority to certify a virtual pilotless aircraft for use in civil airspace.为了让民航协调员在规避风险方面满意,研究人员与英国民航局一起验了虚拟的无人机用于民用空域的可行性,The intention is not to certify an actual aircraft, but for both sides to learn what will be required to do so.其目的并非是要对真正的无人机进行验,而是为了让双方了解需要为此做些什么。Some of the technologies being developed are also likely to find their way into manned aircraft as a backup for pilots, and possibly for cars too.开发出来技术中有一些可能作为飞行员的后备而应用到有人驾驶飞机,还有可能应用到汽车上。Systems that provide automatic braking and motorway-lane control, for instance, aly feature in many types of car.例如,许多种的汽车都已经配备了自动刹车及公路车道控制系统。These features take cars some of the way towards autonomy.这些功能让汽车走上了无人驾驶之路。But driverless cars, like pilotless planes, will have to fit in with existing infrastructure and regulations, not least insurance liability, before they can take off.但是无人驾驶汽车与无人驾驶飞机一样,在出发前,需要先符合现有的基础设施及规章,尤其是明确保险责任。 /201401/272133

Yael,What are you trying to do?雅埃尔,你在干嘛?Im trying to strike this match on the fire place,so I can start a fire.我正试图划燃火柴点燃壁炉,这样我就能有火了。Are you using the right kind of match?你用对火柴了吗?What do you mean?Isnt a match a match?你是什么意思?火柴不就是火柴吗?Nope,There are two different types: safety matches and strike-anywhere matches.大错特错,目前有两种不同的火柴:安全火柴,和那一种在哪里划一下都可以点燃的火柴。Safety matches are the kind that light only when struck on the striking surface on the side of a matchbox.所谓安全火柴,指的就是那种只有在火柴盒表面特定的,某一个可以划燃火柴的区域上才能点燃的火柴。A striking surface consists of sand, powdered glass, and a chemical called red phosphorus.这样的易燃表面是由沙子、玻璃粉、和一种叫做红磷的化学物质构成。The tip of a safety match is made of glass powder, sulfur, and an oxidizing agent–a chemical necessary to keep a flame burning.而火柴头是由玻璃粉,硫磺和一种氧化剂组成-这种氧化剂则是保持火苗能持续燃烧的必需化学物质。When a safety match scrapes against a striking surface, the glass powder on the striking surface and match head rub together, creating enough heat to turn a bit of the red phosphorus on the striking surface into white phosphorus.当你用一根安全火柴去擦这个易燃的表面时,表面的玻璃粉和火柴头相互擦,然后产生出了足够的热量,该热量可以使得易燃表面的红磷转化成为白磷。The white phosphorus ignites in air, passing ignition across to the match head.白磷在空气中会进行燃烧,然后就点燃了火柴头。Sounds like we have a chemical reaction thing going?听起来里面有些化学反应的门道?Thats right.的确如此。This starts a chemical reaction that uses the oxidizing agent on the match to produce oxygen gas.这个过程中引发了一场化学反应,在这个反应中火柴上的氧化剂产生了氧气。Combined with the heat, the oxygen gas causes the sulfur to catch fire, which then sps to the wood of the match.与足够的热量相混合后,氧气引发硫磺着火,之后火苗就会逐渐延伸到火柴另一端的木制部分。A strike anywhere match works almost the same way, except the red phosphorus is included in the match head.那种在任何地方都能点燃的火柴,和这种安全火柴的工作原理都是基本相同的,但是这种火柴的火柴头上就含有红磷。So, a strike anywhere match can be lit by striking the match against any hard surface.因此,只要将这种火柴的火柴头与硬物表面进行擦就可以燃烧。 /201310/259458

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