制约因素

Diacetyl is signal products of ripeness of beer fermentation and proper content of higher alcohols could make beer products full and mild in taste, but excessive higher alcohols not only bring beer peculiar smell but also make beer toxic and ebriety caused by alcohols, so superscale of diacetyl and higher alcohols had become restrictive factors and outstanding contradictions of improving beer qualities, especially in producing low cost beer products fermented by elevating fermentation temperature, shortening fermentation period and increasing content of subsidiary materials.

双乙酰也是啤酒发酵成熟的标志物质，过量的双乙酰给啤酒带来不愉快的"馊饭味"，而适量的高级醇可使酒体丰满圆润、口感柔和协调，但高级醇含量过高，不仅会给啤酒带来异杂味，还易发生醇类中毒，导致醉酒。因此，双乙酰和高级醇超量已成为制约啤酒质量的重要因素，特别是在提高温度、缩短周期、增加辅料的低成本快速发酵中，这一问题更加突出。

Teachers are the most valuable resource and universities colleges overall efficiency of the decisive factor.

教师是高校最宝贵的资源和制约高校整体工作效能的决定性因素。

Animal disease is a major factor to restrict animal husbandry development and encumber international trade of animal products chronically. It's also a potential danger to human beings.

动物疫病是长期制约畜牧业发展和阻碍国际间畜产品贸易的重要因素，也是危害人民食品安全的重要隐患。

Southwest ern China is a mountainous area,and its environmental background is advantageous for the disaster formation.

中国西南地区多为山区，其环境背景有利于灾害的形成，成为制约西南地区经济发展的主要因素之一。

The low yield in seed production is an important limiting factor for the development of japonica hybrid rice, and the stigma exsertion rate of male sterile lines has a key effect on seed yield of japonica hybrid rice.

制种产量低是制约杂交粳稻发展的重要因素，而不育系柱头外露率是影响杂交粳稻制种产量的关键。

The frangibility of tourism determines it development is easily restricted by exterior factors, and the exteriority will cannot be expected and controlled by tourism itself.

旅游业的脆弱性决定了它的发展极其容易受到诸多内外部因素的制约，而这种外部性往往是旅游业本身所难以预料和控制的。

As a vital important part of the system, the port fairway capacity is influenced by many complex factors.

航道作为服务系统中至关重要的一个环节，其通过能力受到许多复杂因素的制约。

The famine is one of the main factors of restricting the social development.

灾荒是制约社会发展的主要因素之一。

In the past hundreds of years, with the limitation of many factors such as productivity and feudalization, the Mongolian have been used to cooperative animal production.

千百年来由于受生产力和封建制度等多种因素的制约，蒙古族历来就有合作生产的习惯。

The flimsiness of the tour industry comes to a decision its development very be subjected to easily many inside the check and supervision of the exterior factor, but this kind of exterior is usually the tour industry hard anticipate and control of.

问题补充：旅游业的脆弱性决定了它的发展极其容易受到诸多内外部因素的制约，而这种外部性往往是旅游业本身所难以预料和控制的。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。