美國(guó)簽證形勢(shì)整體開始發(fā)生轉(zhuǎn)變，敏感專業(yè)的審查周期從以前的長(zhǎng)達(dá)兩個(gè)月縮短到2~3周，且因?qū)I(yè)審查而遭遇申請(qǐng)失敗的人數(shù)極少。但是，如果申請(qǐng)者所學(xué)的專業(yè)屬于敏感專業(yè)，為了能按時(shí)到達(dá)學(xué)校，一定要提早向所在轄區(qū)的大使館或者領(lǐng)事館申請(qǐng)簽證。

　　The State Department maintains a Technical Alert List, also known as the sensitive major list, to guide their evaluation of visa submission.

　　Sorted by rate.

　　CRITICAL FIELDS LIST

　　A. CONVENTIONAL MUNITIONS: Technologies associated with:

　　—— Warheads and other large caliber projectiles

　　—— Reactive armor and warhead defeat systems

　　—— Fusing and arming systems.

　　—— Electronic countermeasures and systems

　　—— New or novel explosives and formulations

　　—— Automated explosive detection methods and equipment

　　B. NUCLEAR TECHNOLOGY: Technologies associated with

　　production and use of nuclear material for both peaceful and military applications. Included are technologies for:

　　—— Enrichment of fissile material

　　—— Reprocessing irradiated nuclear fuel to recover produced

　　plutonium

　　—— Production of heavy water for moderator material

　　—— Plutonium and tritium handling

　　Also, certain associated technologies related to nuclear physics and/or nuclear engineering. Includes materials,equipment or technology associated with:

　　—— Power reactors, breeder and production reactors

　　—— Fissile or special nuclear materials

　　—— Uranium enrichment, including gaseous diffusion, centrifuge, aerodynamic, chemical, Electromagnetic Isotopic Separation (EMIS), Laser Isotope Separation

　　(LIS)

　　—— Spent fuel reprocessing, plutonium, mixed oxide nuclear research

　　Inertial Confinement Fusion (ICF)

　　—— Magnetic confinement fusion

　　—— Laser fusion, high power lasers, plasma,

　　—— Nuclear fuel fabrication including Mixed Oxide (uranium-

　　plutonium) fuels (MOX)

　　—— Heavy water production

　　—— Tritium production and use