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IC200UDR010-BF 在多體計(jì)算中，我們通常利用Bethe-Salpeter方程計(jì)算有頂角修正的各種極化率，圖形上對(duì)應(yīng)著把上述完全頂角函數(shù)F的四個(gè)外腳兩兩連接起來，如下圖左圖所示。實(shí)際上，通過完全頂角函數(shù)我們也可以計(jì)算單粒子格林函數(shù)的自能，如下圖右圖所示。
(b)圖初看起來沒有那么熟悉，其實(shí)把完全頂角函數(shù)用其階近似U替代，就可以發(fā)現(xiàn)是我們熟悉的二階自能圖中的那個(gè)相連拓?fù)洳坏葍r(jià)圖形。而F是包含了所有頂角相互作用的完整表示，如果我們可以嚴(yán)格計(jì)算得到F，那么通過（b）計(jì)算出的自能也將是嚴(yán)格的。通過F與自能的關(guān)系（b），原則上，我們可以構(gòu)造出來一個(gè)完全自洽的理論，即通過計(jì)算兩粒子完全頂角函數(shù)，從而計(jì)算單粒子自能，再反過來通過單粒子格林函數(shù)求源項(xiàng)導(dǎo)數(shù)而計(jì)算新的完全頂角函數(shù)。這樣的自洽過程把F與自能的關(guān)系（b）及Bethe-Salpeter方程連接在一起，形成了一個(gè)完整的同時(shí)具有單粒子和兩粒子自洽性的閉合循環(huán)。這顯然要比僅僅只有單粒子自洽性的量子多體方法要好。我們常見的格林函數(shù)微擾方法，例如Hartree-Fock、二階微擾論、fluctuation-exchangeapproximation(FLEX，漲落交換近似)、non-crossingapproximation（非交叉近似）等等，都是僅有單粒子層次上的自洽性。它們?cè)趦闪Ｗ訉哟紊喜痪哂凶郧⑿浴與自能的關(guān)系（b）及Bethe-Salpeter方程都是嚴(yán)格的，如果我們可以嚴(yán)格的計(jì)算得到完全頂角函數(shù)，我們預(yù)想的同時(shí)具有兩粒子和單粒子自洽性的多體理論，自然也是一個(gè)嚴(yán)格的理論。但是現(xiàn)實(shí)是我們無法嚴(yán)格而完整的計(jì)算出完全頂角函數(shù)。它是一個(gè)依賴于三個(gè)獨(dú)立動(dòng)量和獨(dú)立頻率的函數(shù)，大部分情況下我們得不到它的閉合表達(dá)形式。利用數(shù)值計(jì)算，也存在實(shí)際困難。動(dòng)量空間是具有周期邊條件的，但是松原頻率空間沒有周期性的，原則上所有的頻率都會(huì)貢獻(xiàn)自能中的內(nèi)部變量求和。目前已知的所有數(shù)值計(jì)算辦法（包括量子蒙特卡洛和精確對(duì)角化）都無法得到F的全部信息。因此，我們常常不得不利用Bethe-Salpeter方程做些近似。簡(jiǎn)單的想法是對(duì)每個(gè)channel里不可約的頂角函數(shù)Γ近似處理，然后利用Bethe-Salpeter方程迭代計(jì)算出F。因?yàn)槿齻(gè)channel里的F是等價(jià)的，只需要計(jì)算一個(gè)最簡(jiǎn)單的particle-holehorizontalchannel里的Bethe-Salpeter方程即可。然而，為什么嚴(yán)格的推導(dǎo)會(huì)給我們?nèi)齻(gè)不同channel的Bethe-Salpeter方程呢，這其中隱含了什么重要的信息嗎？實(shí)際上這個(gè)三個(gè)Bethe-Salpeter方程并不是獨(dú)立的。當(dāng)我們?cè)噲D去近似某一個(gè)Γ的時(shí)候，我們很可能就會(huì)破壞其他另外兩個(gè)channel中的Bethe-Salpeter方程。這是因?yàn)橥耆斀呛瘮?shù)F具有一個(gè)非常重要的對(duì)稱性-crossingsymmetry。它連接了這三個(gè)Bethe-Salpeter方程，即通過crossingsymmetry我們總是可以把其中的一個(gè)Bethe-Salpeter方程變成另外一個(gè)。當(dāng)然，只有Γ是嚴(yán)格的，或者對(duì)其做了恰當(dāng)?shù)慕疲拍鼙ＷC這一點(diǎn)。很可惜，目前，我們常見的單粒子自洽理論，包括前述的Hartree-Fock、二階微擾論、fluctuation-exchangeapproximation(FLEX，漲落交換近似)、non-crossingapproximation（非交叉近似）等等都不滿足這一點(diǎn)。通過他們計(jì)算得到的兩粒子頂角函數(shù)都破壞了crossingsymmetry。什么是crossingsymmetry呢？它是兩粒子頂角函數(shù)因?yàn)橘M(fèi)米子的交換反對(duì)易性而具有的一個(gè)特性。如果我們?nèi)我饨粨Q兩個(gè)費(fèi)米子算符，就會(huì)得到一個(gè)額外的負(fù)號(hào)。
兩粒子頂角函數(shù)具有和庫侖排斥力一樣的二次量子化形式，這里我們簡(jiǎn)單的把其系數(shù)寫成算符指標(biāo)的一個(gè)函數(shù)F(12;34)。在上式中我們分別交換了C2和C4兩個(gè)湮滅算符，及C2和C3一對(duì)產(chǎn)生湮滅算符。通過重新改寫啞元，我們得到如下的頂角函數(shù)之間的關(guān)系。
IC200UDR010-BF 華銳SL1500/77風(fēng)機(jī)備品備件
華銳SL1500/82型風(fēng)機(jī)備品備件
風(fēng)機(jī)機(jī)型華銳SL1500/82
新疆金風(fēng)GW77/1500 型風(fēng)力發(fā)電機(jī)組
新疆金風(fēng)S50/750 風(fēng)力發(fā)電機(jī)組
3MW風(fēng)力發(fā)電機(jī) 3MW風(fēng)機(jī)機(jī)艙柜
SCS溫度模塊 PTAI 216：bachmann XE82風(fēng)機(jī)
模擬量輸入/輸出模塊 AIO288廠家：bachmann：適用于XE82風(fēng)機(jī)
FL1500風(fēng)機(jī)
金風(fēng)1.5MW風(fēng)機(jī)
數(shù)字量輸入/輸出模塊 DIO280 數(shù)量1
SCS溫度模塊 Bachmann PTAI 216 數(shù)量1
CAN總線從模塊CS200/N 內(nèi)帶ISI222、AIO288、DIO248的驅(qū)動(dòng)程序以及和CM202的通訊程序
編碼器接口模塊 ISI222 數(shù)量1
全新原裝華銳風(fēng)機(jī) WTCBA200A crowbar 正品保障windtec
2 主控制器WT98 ABB/WT98 07KT98 個(gè) 1 3
主控制器WT97 ABB/WT97 07KT97 個(gè) 1
4 巴赫曼PLC（塔基） 整套 個(gè) 1
5 PLC-電源模塊 24VDC/68W NT255 個(gè) 1
6 PLC-中央處理器模塊 128MB MPC240 個(gè) 1
8 PLC-數(shù)字I/0模塊 24VDC/1A DIO216 個(gè) 1
9 PLC-溫度記錄模塊 24VDC PTAI216
PLC模塊/通訊RS204
PLC模塊/網(wǎng)口EM203
PLC模塊DI232
PLC模塊DO232
角度控制元件 ISI222
PLC快速數(shù)據(jù)總線模塊FM211
PLC數(shù)字輸入輸出模塊DIO216
PLC模塊CM202
光纖傳輸接口模塊 FS211/N
ALLEN BRADLEY 1785-LT PLC-5/15 PROCESSOR MODULE, 6K MEMORY
ALLEN BRADLEY 1785-LT2 PLC-5/25 PROCESSOR MODULE, 13K MEMORY
ALLEN BRADLEY 1785-LT3 PLC-5/12 PROCESSOR MODULE, 6K MEMORY
ALLEN BRADLEY 1785-LT4 PLC-5/10 PROCEESOR MODULE, 6K MEMORY
ALLEN BRADLEY 1785-M100 PLC-5/80 EEPROM MEMORY CARTRIDGE,100K
ALLEN BRADLEY 1785-ME16 EEPROM MEMORY CARTRIDGE
ALLEN BRADLEY 1785-ME32 PLC-5/30 EEPROM MEMORY CARTRIDGE
ALLEN BRADLEY 1785-ME64 PLC-5/40 5/60 EEPROM MEMORY CARTRIDGE
ALLEN BRADLEY 1785-MJ 8K EEPROM MEM
ALLEN BRADLEY 1785-MK 16K EEPROM CARTRIDGE
ALLEN BRADLEY 1785-MS PLC-5 8K RAM MEMORY MODULE
ALLEN BRADLEY 1785-MR 4K RAM MEMORY CARTRIDGE
ALLEN BRADLEY 1785-O5C PLC
ALLEN BRADLEY 1785-TAM THIN-WIRE TRANSCEIVER CABLE KIT
ALLEN BRADLEY 1785-TAS THIN-WIRE TRANSCEIVER CABLE KIT
ALLEN BRADLEY 1785-TBM THIN-WIRE TRANSCEIVER CABLE KIT
ALLEN BRADLEY 1785-TBS THIN-WIRE TRANSCEIVER CABLE KIT
ALLEN BRADLEY 1785-TR10B2 AUI TO THIN WIRE ENET TRA
ALLEN BRADLEY 1785-TR10B5 AUI TO THIN WIRE ENET TR
ALLEN BRADLEY 1785-TR10BF AUI TO F.OPTIC ENET TRANS
ALLEN BRADLEY 1785-TR10BT AUI TO TW PAIR ENET TRANS
ALLEN BRADLEY 1785-V30B VME PLC 5/30 CONTROLLER 32K WORD SPAM
ALLEN BRADLEY 1785-V40B VME PLC 5/40 CONTROLLER 48K WORD SPAM
ALLEN BRADLEY 1785-V40L VME PLC 5/40 CONTROLLER W/EXT LOCAL PORT
ALLEN BRADLEY 1785-V80B PROCESSOR MODULE VME/PLC5 100K WORD SRAM
1791
MFR. PART NUMBER DESCRIPTION
ALLEN BRADLEY 1791-OA16 I/O BLOCK 120VAC 16 POINT OUTPUT
ALLEN BRADLEY 1791-OA32 /O BLOCK 120VAC 32 POINT MODULE
ALLEN BRADLEY 1791-OB16 I/O BLOCK 24VAC 16 POINT OUTPUT
ALLEN BRADLEY 1791-OB32 I/O BLOCK 24VAC 32 POINT OUTPUT
ALLEN BRADLEY 1791-16AO I/O BLOCK 120VAC 16 POINT MODULE (16 INPUT)
ALLEN BRADLEY 1791-16AC I/O BLOCK 120VAC 32 POINT
ALLEN BRADLEY 1791-16BO BLOCK I/O EXPANSION 24VDC 16 IN SINK RTB
ALLEN BRADLEY 1791-16BC I/O BLOCK MODULE 24VDC 32 POINT
ALLEN BRADLEY 1791-24A8 I/O BLOCK 120VAC 32 POINT MODULE
ALLEN BRADLEY 1791-24AR I/O BLOCK 120VAC 32 POINT MODULE
ALLEN BRADLEY 1791-24B8 BLOCK I/O, 24V DC, 32 POINT MODULE
ALLEN BRADLEY 1791-24BR BLOCK I/O, 24V DC, 32 POINT MODULE
ALLEN BRADLEY 1791-32AO /O BLOCK 120VAC 32 POINT INPUT MODULE
ALLEN BRADLEY 1791-32BO I/O BLOCK 24V DC 32 POINT MODULE
ALLEN BRADLEY 1791-8AC I/O BLOCK 120VAC 16 POINT MODULE
ALLEN BRADLEY 1791-8AR I/O BLOCK 120VAC 16 POINT MODULE
ALLEN BRADLEY 1791-8BC I/O BLOCK 24VDC 16 POINT MODULE
ALLEN BRADLEY 1791-8BR I/O BLOCK 24VDC 16 POINT MODULE
ALLEN BRADLEY 1791-AIC ISOLATED LINK COUPLER
ALLEN BRADLEY 1791-IOBA I/O BLOCK 24VDC 16 POINT
ALLEN BRADLEY 1791-IOBB I/O BLOCK 24VDC 16 POINT
ALLEN BRADLEY 1791-IOBW I/O BLOCK 24VDC 64 PT MODULE
ALLEN BRADLEY 1791-IOBX I/O BLOCK 24VDC 128POINT MODULE
ALLEN BRADLEY 1791-IOVW I/O BLOCK 24VDC 64 POINT MODULE
ALLEN BRADLEY 1791-IOVX I/O BLOCK 24VDC 128POINT MODULE
ALLEN BRADLEY 1791-N4C2 I/O BLOCK 120VAC 6 POINT ANALOG MODULE
ALLEN BRADLEY 1791-N4V2 I/O BLOCK 120VAC 6 POINT ANALOG MODULE
ALLEN BRADLEY 1791-NDC I/O BLOCK 120VAC 6 POINT ANALOG MODULE
ALLEN BRADLEY 1791-NDV I/O BLOCK 120VAC 6 POINT ANALOG MODULE
ALLEN BRADLEY 1791-TB2 TERMINAL, 30 POSITION, 10 PCS KIT
ALLEN BRADLEY 1791D-OB16P 24VDC I/O BLOCK 16 OUT SOURCE REMOVABLE TAB
ALLEN BRADLEY 1791D-OB16PX BLOCK I/O EXPANSION 24VDC 16 OUT SOURCE RTB
ALLEN BRADLEY 1791D-OV16P 24VDC I/O BLOCK EXPANSION 16 IN SINK RTB
ALLEN BRADLEY 1791D-OV16PX BLOCK I/O EXPANSION 24VDC 16 OUT SOURCE RTB
ALLEN BRADLEY 1791D-16BO BLOCK I/O 24VDC 16 IN SINK REMOVABLE TB
ALLEN BRADLEY 1791D-16BOX 24VDC I/O BLOCK EXPANSION 16 IN SINK RTB
ALLEN BRADLEY 1791D-16VO BLOCK I/O EXPANSION 24VDC 16 OUT SOURCE RTB
ALLEN BRADLEY 1791D-16VOX BLOCK I/O EXPANSION 24VDC 16 OUT SOURCE RTB
ALLEN BRADLEY 1791D-8B8P 24VDC I/O BLOCK 8 IN SINK 8 OUT SOURCE RTB
1794
MFR. PART NUMBER DESCRIPTION
ALLEN BRADLEY 1794-ACN15 CTRLNET ADAPTER
ALLEN BRADLEY 1794-ACNR15 CTRLNET ADAPTER
ALLEN BRADLEY 1794-AND DEVICENET ADAPTER
ALLEN BRADLEY 1794-ASB I/O ADAPTER
ALLEN BRADLEY 1794-ASB2 I/O ADAPTER
ALLEN BRADLEY 1794-IA16 16 INPUT MODULE
ALLEN BRADLEY 1794-IA8 8 INPUT MODULE
ALLEN BRADLEY 1794-IA8I 8 INPUT MODULE
ALLEN BRADLEY 1794-IB10X0B6 I/O MODULE
ALLEN BRADLEY 1794-IB16 16 INPUT MODULE
ALLEN BRADLEY 1794-IB8 8 INPUT MODULE
ALLEN BRADLEY 1794-IC16 16 INPUT MODULE
ALLEN BRADLEY 1794-ID2 PULSE COUNT MOD
ALLEN BRADLEY 1794-IE4X0E2 I/O MODULE
ALLEN BRADLEY 1794-IE8 8 INPUT MODULE
ALLEN BRADLEY 1794-IF2X0F21 O/I MODULE
ALLEN BRADLEY 1794-IF41 4 INPUT MODULE
ALLEN BRADLEY 1794-IJ2 FREQ INPUT MODULE
ALLEN BRADLEY 1794-IM8 8 INPUT MODULE
ALLEN BRADLEY 1794-IR8 RTD INPUT MOD
ALLEN BRADLEY 1794-IRT8 RTD MODULE
ALLEN BRADLEY 1794-IT8 INPUT MODULE
ALLEN BRADLEY 1794-IV16 16 INPUT MODULE
ALLEN BRADLEY 1794-OA16 16 OUTPUT MODULE
ALLEN BRADLEY 1794-OA8 8 OUTPUT MODULE
ALLEN BRADLEY 1794-OA8I 8 OUTPUT MODULE
ALLEN BRADLEY 1794-OB16 16 OUTPUT MODULE
ALLEN BRADLEY 1794-OB16P 16 OUTPUT MODULE
ALLEN BRADLEY 1794-OB8 8 OUTPUT MODULE
ALLEN BRADLEY 1794-OB8EP 8 OUTPUT MODULE
ALLEN BRADLEY 1794-OC16 16 OUTPUT MODULE
ALLEN BRADLEY 1794-OE4 4 OUTPUT MODULE
ALLEN BRADLEY 1794-OF4I 4 OUTPUT MODULE
ALLEN BRADLEY 1794-OM8 8 OUTPUT MODULE
ALLEN BRADLEY 1794-OV16 16 OUTPUT MODULE
ALLEN BRADLEY 1794-OV16P 16 OUTPUT MODULE
ALLEN BRADLEY 1794-OW8 8 OUTPUT MODULE
ALLEN BRADLEY 1794-PS1 POWER SUPPLY MODULE
ALLEN BRADLEY 1794-TB3 TERM BASE UNIT
ALLEN BRADLEY 1794-TB3G TERM BASE UNIT
ALLEN BRADLEY 1794-TB3GS TERM BASE UNIT
ALLEN BRADLEY 1794-TB3S TERM BASE UNIT
ALLEN BRADLEY 1794-TB3T TERM BASE UNIT
ALLEN BRADLEY 1794-TB3TS TERM BASE UNIT
ALLEN BRADLEY 1794-TBN TERM BASE UNIT
ALLEN BRADLEY 1794-TBNF TERM BASE UNIT
人機(jī)界面(觸摸屏)|WT205 LX700/DD256/CF512/VX
巴赫曼人機(jī)界面（觸摸屏）WT205 LX800/DD512/CF512/VX
巴赫曼人機(jī)界面(觸摸屏)|WT205 LX700/DD256/CF512/VX||
巴赫曼WT205/T/BE1/LX7人機(jī)界面
24V電源模塊 NT255
MPC240控制器 MPC270
數(shù)字量輸入輸出模塊 DIO280
數(shù)字量輸入輸出模塊 DIO232
模擬量輸入輸出模塊 AIO288
DP模塊 DPM200
背板 BS212
編碼器模塊 IS1202/IS1222
FAST-BUS 模塊 FM211
風(fēng)機(jī)PL模塊ISI222 機(jī)艙
風(fēng)機(jī)PL模塊MX213 機(jī)艙
風(fēng)機(jī)PL模塊FM211 塔基
National Instruments PCI-232/8 Serial Port w/ 68 PinCon
NATIONAL INSTRUMENTS 100 Pin 2 meter Cable SH100-100-F
QTY 10 PCBs Blank 68 Pin for National Instruments NEW
National Instruments DAQ Card, PC-DIO-24, 777368-01,NEW
Serial Port w/ 68 PinCon PCI-232/8 National Instruments
National Instruments MC-GPIB IEEE 488.2 PCI Card - NEW!
NATIONAL INSTRUMENT FP-TB-1 USPP FPTB1
NATIONAL INSTRUMENT SCXI-1326 USPP SCXI1326
National Instruments AT-GPIB/TNT IEEE 488 Interface
NATIONAL INSTRUMENTS GPIB-PCIIA IEEE-488.2 181065-01
National Instruments CB-68LPR
NEW NATIONAL INSTRUMENTS CIRCUIT BOARD MODEL AT-GPIB
National Instruments bus interface.Card NB-DIO-32F
Expedited shipping available
National Instruments PCI-Step 184905B-01
Expedited shipping available
National Instruments PCI-232/485 BOARD 4CH 184683E-01
National Instruments VXI-MXI-2 PC to MXIbus Interface
National Instruments GPIB-PCII/IIA 181065-01 Rev.E1 ISA
National Instruments PCI 232/485 8ch board with cable
National Instruments PCI DIO-32HS 183480E-01
National Instruments PCI DIO-32HS 183480F-01
National Instruments 179055-01 GPIB11V-2 Q-BUS New
NATIONAL INSTRUMENTS CFP-DO-401 SOURCING OUTPUT 16-CH
National Instruments NI MXI-2 MXI2 Cable
NATIONAL INSTRUMENTS PCI-232 16-CH PCD-DIO-24 CABLE DAQ
National Instruments VXI-MXI-2 Module
National instruments 181065-01 Rev.E
National Instruments SH100100 Shielded Cable, New
National Instruments Lab-PC-1200 NI DAQ Card ISA
NATIONAL INSTRUMENT 777459-04 NSFP 77745904
National Instruments SCXI 1000 4-slot Chassis working
Enlarge
NI NATIONAL INSTRUMENTS DIO CARD ISA PC-DIO-96
NATIONAL INSTRUMENTS. GPIB-PCII
NATIONAL INSTRUMENTS NI 185205A-01 CABLE PSH32-4DB9
NATIONAL INSTRUMENTS. AT-GPIB/TNT
National Instruments. SCXI-1163R. 32CH.
National Instruments MXI2/2 1-meter cable 182802A-001
NATIONAL INSTRUMENTS EISA-GPIB IEEE-488.2 182525D-01
NI National Instruments DIO Card ISA PC-DIO-96/PnP
National Instruments 181830 AT-GPIB/TNT ISA Board 18183
One-day shipping available
National Instruments AT-MIO-16E-2 12 bit DAQ
National Instruments I/O board LAB-NB S/N 003100
Expedited shipping available
National Instruments 886207-01 CCA,AT-GPIB.2
CONAR INSTRUMENTS 250 NATIONAL RADIO SCOPE OSCILLOSCOPE
Enlarge
National Instruments PCI-DIO-96 96-bit Dig. I.O. card
NATIONAL INSTRUMENTS GPIB-120A BUS EXPANDER/ISOLATOR
Expedited shipping available
National Instruments PCI-232/485, 2CH
One-day shipping available
National Instruments 777421L-04 Software for WIN NT/98
One-day shipping available
SAVE $50 NATIONAL INSTRUMENTS 68 Pin Cable SH6868 1m
National Instruments PCI1200 with I/O Board- NI Labview
NATIONAL INSTRUMENTS 68 Pin Cable SH6868 1m - SAVE $50
National Instruments Cable Assy IMAG-A2504-1 DB25 BNC
NATIONAL INSTRUMENTS, SCXI-1163R, SOLID STATE RELAY
National Instruments AT-MIO-16X 181610-01 DAQ I/O Board
National instruments NB5 Ribbon Cable 181304-20 PC-DIO
NATIONAL INSTRUMENTS 2M CABLE SH 96-96 183228A-02
National Instruments Cable: 186823A-01: 1-meter NI1409
National Instruments SCXI-1160 16-Channel Relay Board
Phoenix Contact National Instruments - 2281092 FLKM 60
Expedited shipping available
NATIONAL INSTRUMENTS AT-GPIB/TNT ASSY181830E ,IEEE488.2
NATIONAL INSTRUMENTS AT-GPIB/TNT PLUG N PLAY 183663C-01
NATIONAL INSTRUMENTS VXI-MXI-2 VXIBUS C-SIZE MODULE.
National Instruments PCI-6503 Card
National Instruments PCI-232/485 , 4CH board
National instrument PCI-6503 interface card 185183A-01
VHDCI Breakout for National Instruments NI 'M' Series
Expedited shipping available
VHDCI Breakout for National Instruments NI PCI-6229
Expedited shipping available
VHDCI Breakout for National Instruments NI PCI-6220
Expedited shipping available
NATIONAL INSTRUMENT NI-CFP-CB-1 USPP NICFPCB1
National Instruments NB-GPIB Mac NuBus Card
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