CN1290797C - Electronic emitting material of molybdenum rare earth containing cerium and preparation process thereof - Google Patents
Electronic emitting material of molybdenum rare earth containing cerium and preparation process thereof Download PDFInfo
- Publication number
- CN1290797C CN1290797C CN 200510077234 CN200510077234A CN1290797C CN 1290797 C CN1290797 C CN 1290797C CN 200510077234 CN200510077234 CN 200510077234 CN 200510077234 A CN200510077234 A CN 200510077234A CN 1290797 C CN1290797 C CN 1290797C
- Authority
- CN
- China
- Prior art keywords
- rare earth
- molybdenum
- ammonium molybdate
- present
- water solution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 229910052761 rare earth metal Inorganic materials 0.000 title claims abstract description 41
- 239000000463 material Substances 0.000 title claims abstract description 32
- 229910052750 molybdenum Inorganic materials 0.000 title claims abstract description 27
- 239000011733 molybdenum Substances 0.000 title claims abstract description 27
- -1 molybdenum rare earth Chemical class 0.000 title claims abstract description 12
- 238000002360 preparation method Methods 0.000 title claims abstract description 7
- 229910052684 Cerium Inorganic materials 0.000 title claims description 14
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 title claims description 13
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims abstract description 37
- 150000002910 rare earth metals Chemical class 0.000 claims abstract description 29
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims abstract description 28
- 235000018660 ammonium molybdate Nutrition 0.000 claims abstract description 17
- APUPEJJSWDHEBO-UHFFFAOYSA-P ammonium molybdate Chemical compound [NH4+].[NH4+].[O-][Mo]([O-])(=O)=O APUPEJJSWDHEBO-UHFFFAOYSA-P 0.000 claims abstract description 15
- 239000011609 ammonium molybdate Substances 0.000 claims abstract description 15
- 229940010552 ammonium molybdate Drugs 0.000 claims abstract description 15
- 238000000034 method Methods 0.000 claims abstract description 15
- 229910001404 rare earth metal oxide Inorganic materials 0.000 claims abstract description 12
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 8
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 8
- 239000001257 hydrogen Substances 0.000 claims abstract description 8
- 238000004663 powder metallurgy Methods 0.000 claims abstract description 7
- 229910002651 NO3 Inorganic materials 0.000 claims abstract description 5
- 239000000243 solution Substances 0.000 claims description 20
- 239000000084 colloidal system Substances 0.000 claims description 10
- 239000000843 powder Substances 0.000 claims description 7
- 239000007864 aqueous solution Substances 0.000 claims description 4
- 239000002994 raw material Substances 0.000 claims description 2
- 239000010406 cathode material Substances 0.000 abstract description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 13
- 229910052746 lanthanum Inorganic materials 0.000 abstract description 9
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 abstract description 9
- 239000003870 refractory metal Substances 0.000 abstract description 2
- 108010010803 Gelatin Proteins 0.000 abstract 3
- 229920000159 gelatin Polymers 0.000 abstract 3
- 239000008273 gelatin Substances 0.000 abstract 3
- 235000019322 gelatine Nutrition 0.000 abstract 3
- 235000011852 gelatine desserts Nutrition 0.000 abstract 3
- 230000004913 activation Effects 0.000 abstract 2
- 229910000421 cerium(III) oxide Inorganic materials 0.000 abstract 2
- 239000000203 mixture Substances 0.000 abstract 1
- RUDFQVOCFDJEEF-UHFFFAOYSA-N yttrium(III) oxide Inorganic materials [O-2].[O-2].[O-2].[Y+3].[Y+3] RUDFQVOCFDJEEF-UHFFFAOYSA-N 0.000 abstract 1
- 235000015165 citric acid Nutrition 0.000 description 9
- 238000012545 processing Methods 0.000 description 7
- 238000010438 heat treatment Methods 0.000 description 6
- BXJPTTGFESFXJU-UHFFFAOYSA-N yttrium(3+);trinitrate Chemical compound [Y+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O BXJPTTGFESFXJU-UHFFFAOYSA-N 0.000 description 6
- 238000003754 machining Methods 0.000 description 5
- 229910052751 metal Inorganic materials 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- HSJPMRKMPBAUAU-UHFFFAOYSA-N cerium(3+);trinitrate Chemical compound [Ce+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O HSJPMRKMPBAUAU-UHFFFAOYSA-N 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 4
- 238000009413 insulation Methods 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 150000002823 nitrates Chemical class 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 4
- 238000003466 welding Methods 0.000 description 4
- 238000003763 carbonization Methods 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 238000010000 carbonizing Methods 0.000 description 1
- 239000011195 cermet Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000008236 heating water Substances 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 230000002285 radioactive effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Landscapes
- Powder Metallurgy (AREA)
- Discharge Lamp (AREA)
Abstract
The present invention belongs to the field of rare-earth refractory metal cathode materials. The existing cathode materials can not meet the requirements for electronic tubes and magnetrons with high cathode emission capability. The material of the present invention is characterized in that the material of the present invention is prepared from 4 to 30 wt% of Ce2O3 (rare earth oxide) or the mixture of Ce2O3 and Y2O3, and molybdenum as the rest. The preparation method of the present invention comprises: a rare earth nitrate water solution is added to an ammonium molybdate water solution according to the proportion that rare earth oxides accounts for 4 to 30 wt% of the total weight of rare earth molybdenum powder, and a citric acid solution is added to the rare earth nitrate water solution and the ammonium molybdate water solution; the citric acid solution, the rare earth nitrate water solution and the ammonium molybdate water solution are processed in a water bath mode at the temperature of 60 to 90 DEG C and dried at the temperature of 100 to 150 DEG C so as to form gelatin; C and N in the gelatin are removed at the temperature of 500 to 550 DEG C under the atmosphere condition; the gelatin is reduced in the hydrogen atmosphere at the 500 to 550 DEG C for 2 to 4 hours in the first step, and then reduced at the temperature of 900 to 1000 DEG C for 1 to 2 hours in the second step so as to obtain the rare earth molybdenum powder; the rare earth molybdenum powder is prepared into the material of the present invention by using the powder metallurgy method. The secondary emission coefficient of the material of the present invention is greater than that of the cathode material containing lanthanum; the activation temperature corresponding to the maximum secondary emission coefficient is smaller than the optimal activation temperature of the cathode material containing lanthanum.
Description
Technical field
A kind of electronic emitting material of molybdenum rare earth that contains cerium and preparation method thereof belongs to rare earth refractory metal cathode material technical field.
Background technology
That use in high power valve and magnetron at present mainly is ThO
2Negative electrode (is respectively ThO
2-W hot cathode and ThO
2-W cermet negative electrode and ThO
2Indissoluble melts metal cavernous body negative electrode), but because Th is a kind of radioactive element, and its half-life is very long, in the preparation process of the production of material and negative electrode, can to human body and environment harm, therefore require the new material substitution of development.In the past, people once developed rare earth molybdenum hot cathode and the secondary emitting material that contains lanthanum
[1-2], [1] is Wang Jinshu, Zhou Meiling, Zhang Jiuxing etc., La
2O
3-Mo cathode surface carburization zone study on mechanism, Acta Metallurgica Sinica, 11 (2000) 1205-1208.[2] be Wang Jinshu, Liu Juan, Zhou Meiling etc., La
2O
3, Y
2O
3The research of-Mo secondary emitting material, China rare earth journal, 1 (2003) 23-26.
In the electron tube of certain model and magnetron, can meet the demands.But because the restriction of its heat emission and secondary emission level, can't satisfy electron tube with higher emission of cathode ability and the instructions for use of magnetron, therefore still need develop new cathode material.
Summary of the invention
The invention provides a kind of rare earth molybdenum cathode material that contains cerium, it have emitting performance good, be easy to machining characteristics.Do not see at present the report of relevant this kind investigation of materials.
The electronic emitting material of molybdenum rare earth that contains cerium provided by the present invention is characterized in that: contain Ce
2O
3A kind of rare earth oxide or Ce
2O
3, Y
2O
3The combination of two kinds of rare earth oxides, above-mentioned rare earth oxide accounts for the 4-30%wt of this emissive material gross weight, and all the other are molybdenum.
The preparation method who contains the electronic emitting material of molybdenum rare earth of cerium provided by the present invention is characterized in that, may further comprise the steps:
(1) take ammonium molybdate as raw material, in ammonium molybdate aqueous solution, add rare earth nitrate aqueous solution, in ammonium molybdate and the rare earth nitrades consumption emissive material by final acquisition, rare earth oxide Ce
2O
3Or Ce
2O
3, Y
2O
3The combination of two kinds of rare earth oxides accounts for emissive material total amount 4-30%wt, adds then citric acid solution, places 60-90 ℃ of water-bath to forming colloidal sol, forms gel in 100-150 ℃ of oven dry then;
(2) with this gel under 500-550 ℃, air atmosphere, decompose to till the C and N element in whole removal colloids;
(3) powder after will decomposing reduces under hydrogen atmosphere, is divided into for two steps to carry out, and the first step is 500-550 ℃, is incubated 2-4 hour; The second step reduction temperature is 900-1000 ℃, and the time is 1-2 hour, obtains the rare earth molybdenum powder, prepares electronic emitting material of molybdenum of the present invention with powder metallurgy process then.
The cathode material that contains cerium of the present invention, its secondary emission coefficient is higher than the cathode material that contains lanthanum.Simultaneously, the activationary temperature that contains cerium negative electrode maximum secondary emissivity factor correspondence is lower than the best activationary temperature that contains the lanthanum cathode material.
Description of drawings:
Fig. 1: 4wt%Ce
2O
3The LogU-LogI curve of-Mo material (embodiment 1)
Fig. 2: 30wt% (Ce
2O
3-Y
2O
3)-Mo (Ce
2O
3: Y
2O
3=1: 3, mass ratio) the secondary emission performance curve of material (embodiment 2)
Fig. 3: 30wt% (Ce
2O
3-Y
2O
3)-Mo (Ce
2O
3: Y
2O
3=1: 2, mass ratio) the secondary emission performance curve of material (embodiment 3)
Fig. 4: 30wt% (Ce
2O
3-Y
2O
3)-Mo (Ce
2O
3: Y
2O
3=2: 1, mass ratio) the secondary emission performance curve of material (embodiment 4)
Embodiment
Example 1, with 9.985 the gram cerous nitrates, 176.698 it is respectively soluble in water that gram ammonium molybdate, 100 restrains citric acids, then cerous nitrate solution and ammonium molybdate solution are mixed, precipitation appears, citric acid solution is slowly added, the precipitation gradually the dissolving, with this mixed solution in 60 ℃ of heating water baths until solution becomes colloidal sol.Colloid in 150 ℃ of oven dry, is decomposed powder to remove C and the N element in the colloid down air atmosphere, 550 ℃.In 550 ℃ hydrogen furnace, be incubated 4h, then temperature risen to 900 ℃ of insulations 1 hour, will handle the doped Ce O that obtains through reduction
2(CeO
2Content is 4%wt) molybdenum powder, adopt powder metallurgy process, make rare earth molybdenum sintered compact with certain size.After machining, make the rare earth molybdenum sheet material of φ 3 * 1mm, it is embedded in the active C powder, the following 1600 ℃ of carbonizing treatment of hydrogen atmosphere are made carbonization rare earth molybdenum hot-cathode.Adopt then method of laser welding that carbonization rare earth molybdenum sheet and molybdenum tube, the metal tungsten wire that is used for heating are welded, through exhaust, activate and make rare earth molybdenum experiment electron tube after processing.Process through activated at, the emission properties of negative electrode is seen Fig. 1, table 1 under the test different temperatures.
Example 2, with 18.9221 the gram cerous nitrates, 63.4676 gram Yttrium trinitrate, 128.7938 it is soluble in water respectively that gram ammonium molybdate, 100 restrains citric acids, then cerous nitrate, Yttrium trinitrate and ammonium molybdate solution are mixed, citric acid solution is slowly added, this mixing solutions is become colloidal sol in 80 ℃ of heating in water bath until solution.Colloid in 120 ℃ of oven dry, is decomposed powder to remove C and the N element in the colloid down air atmosphere, 500 ℃.In 500 ℃ hydrogen furnace, be incubated 3h, then temperature risen to 950 ℃ of insulations 2 hours, will process the doped Ce that obtains through reduction
2O
3And Y
2O
3(Ce
2O
3And Y
2O
3Total amount is 30%wt, wherein Ce
2O
3: Y
2O
3=1: 3, mass ratio) molybdenum powder adopts powder metallurgy process, makes the rare earth molybdenum sintered body with certain size.After machining, make the rare earth molybdenum sheet material of φ 10 * 1.5mm.Adopt then method of laser welding that rare earth molybdenum sheet and molybdenum tube, the metal tungsten wire that is used for heating are welded, through exhaust, activate and make rare earth molybdenum experiment magnetron after processing.Measure the secondary emission coefficients of processing, testing through different activationary temperatures under 600 ℃, see Fig. 2, the maximum secondary emission ratio under the best activationary temperature sees Table 2.
Example 3, with 25.2295 the gram cerous nitrates, 56.4157 the gram Yttrium trinitrate, it is soluble in water respectively that 128.7938 gram ammonium molybdates, 100 restrain citric acids, then cerous nitrate, Yttrium trinitrate and ammonium molybdate solution mixed, citric acid solution is slowly added, this mixing solutions is become colloidal sol in 90 ℃ of water-baths until solution.Colloid in 100 ℃ of oven dry, is decomposed powder to remove C and the N element in the colloid down air atmosphere, 500 ℃.In 500 ℃ hydrogen furnace, be incubated 2h, then temperature risen to 1000 ℃ of insulations 1 hour, will process the doped Ce that obtains through reduction
2O
3And Y
2O
3(Ce
2O
3And Y
2O
3Total amount is 30%wt, wherein Ce
2O
3: Y
2O
3=1: 2, mass ratio) molybdenum powder adopts powder metallurgy process, makes the rare earth molybdenum sintered body with certain size.After machining, make the rare earth molybdenum sheet material of φ 10 * 1mm.Adopt then method of laser welding that rare earth molybdenum sheet and molybdenum tube, the metal tungsten wire that is used for heating are welded, through exhaust, activate and make rare earth molybdenum experiment magnetron after processing.Measure the secondary emission coefficients of processing, testing through different activationary temperatures under 600 ℃, see Fig. 3, the maximum secondary emission ratio under the best activationary temperature sees Table 2.
Example 4, with 50.4590 the gram cerous nitrates, 28.2078 the gram Yttrium trinitrate, it is soluble in water respectively that 128.7938 gram ammonium molybdates, 100 restrain citric acids, then cerous nitrate, Yttrium trinitrate and ammonium molybdate solution mixed, citric acid solution is slowly added, this mixing solutions is become colloidal sol in 90 ℃ of water-baths until solution.This mixing solutions is become colloidal sol in 80 ℃ of heating in water bath until solution.Colloid in 100 ℃ of oven dry, is decomposed powder to remove C and the N element in the colloid down air atmosphere, 500 ℃.In 500 ℃ hydrogen furnace, be incubated 1h, then temperature risen to 950 ℃ of insulations 2 hours, will process the doped Ce that obtains through reduction
2O
3And Y
2O
3(Ce
2O
3And Y
2O
3Total amount is 30%wt, wherein Ce
2O
3: Y
2O
3=2: 1, mass ratio) molybdenum powder adopts powder metallurgy process, makes the rare earth molybdenum sintered body with certain size.After machining, make the rare earth molybdenum sheet material of φ 10 * 1mm.Adopt then method of laser welding that rare earth molybdenum sheet and molybdenum tube, the metal tungsten wire that is used for heating are welded, through exhaust, activate and make rare earth molybdenum experiment magnetron after processing.Measure the secondary emission coefficients of processing, testing through different activationary temperatures under 600 ℃, see Fig. 4, the maximum secondary emission ratio under the best activationary temperature sees Table 2.With the 30% (La that contains lanthanum
2O
3-Y
2O
3The comparing data of)-Mo negative electrode sees Table 3.
The result of table 3 shows, contains the 30wt% (Ce of cerium
2O
3-Y
2O
3)-Mo cathode material (embodiment 4), its secondary emission coefficient is higher than the 30wt% (La that contains lanthanum
2O
3-Y
2O
3)-Mo cathode material.Simultaneously, contain the corresponding activationary temperature (best activationary temperature) of cerium negative electrode maximum secondary emissivity factor (4.51) and be lower than best activationary temperature 600 degree that contain the lanthanum cathode material.
Table 1 Ce
2O
3Zero field current density (the A/cm of-Mo hot cathode
2)
| Temperature (℃) | |
| 1300 | 1.59 |
| 1350 | 2.75 |
| 1450 | 4.17 |
| 1500 | 5.03 |
Table 2 Ce
2O
3-Y
2O
3The secondary emission performance of-Mo negative electrode
| |
1000 | 3.87 |
| |
1200 | 11.11 |
| |
900 | 4.51 |
Table 3, contain the La of lanthanum
2O
3-Y
2O
3-Mo and the Ce that contains cerium
2O
3-Y
2O
3-Mo cathode material (embodiment
4) secondary emission coefficient under different activationary temperatures relatively
Claims (2)
1, contains the electronic emitting material of molybdenum rare earth of cerium, it is characterized in that: contain Ce
2O
3A kind of rare earth oxide or Ce
2O
3, Y
2O
3The combination of two kinds of rare earth oxides, above-mentioned rare earth oxide accounts for the 4-30%wt of this emissive material gross weight, and all the other are molybdenum.
2, the preparation method who contains the electronic emitting material of molybdenum rare earth of cerium according to claim 1 is characterized in that, may further comprise the steps:
Step 1: take ammonium molybdate as raw material, in ammonium molybdate aqueous solution, add rare earth nitrate aqueous solution, in ammonium molybdate and the rare earth nitrades consumption emissive material by final acquisition, rare earth oxide Ce
2O
3Or Ce
2O
3, Y
2O
3The combination of two kinds of rare earth oxides accounts for this emissive material total amount 4-30%wt, adds then citric acid solution, places 60-90 ℃ of water-bath to forming colloidal sol, forms gel in 100-150 ℃ of oven dry then;
Step 2: this gel under 500-550 ℃, air atmosphere, is decomposed to till the C and N element in whole removal colloids;
Step 3: the powder after will decomposing reduces under hydrogen atmosphere, be divided into two the step carry out, the first step is 500-550 ℃, is incubated 2-4 hour; The second step reduction temperature is 900-1000 ℃, and the time is 1-2 hour, obtains the rare earth molybdenum powder, prepares electronic emitting material of molybdenum of the present invention with powder metallurgy process then.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510077234 CN1290797C (en) | 2005-06-20 | 2005-06-20 | Electronic emitting material of molybdenum rare earth containing cerium and preparation process thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510077234 CN1290797C (en) | 2005-06-20 | 2005-06-20 | Electronic emitting material of molybdenum rare earth containing cerium and preparation process thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1693284A CN1693284A (en) | 2005-11-09 |
| CN1290797C true CN1290797C (en) | 2006-12-20 |
Family
ID=35352429
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200510077234 Expired - Fee Related CN1290797C (en) | 2005-06-20 | 2005-06-20 | Electronic emitting material of molybdenum rare earth containing cerium and preparation process thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1290797C (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102351248B (en) * | 2011-09-13 | 2013-06-12 | 武汉理工大学 | Method for synthesizing cerium molybdate material |
| EP3825292A4 (en) * | 2018-07-18 | 2022-04-20 | Tokyo Institute of Technology | COMPLEX OXIDE CERAMIC, PROCESS FOR THEIR PRODUCTION AND SUBJECT |
| CN115533112B (en) * | 2022-10-17 | 2023-10-20 | 北京工业大学 | Method for refining refractory metal by composite rare earth tungsten/molybdate eutectic |
| CN115735947A (en) * | 2022-11-11 | 2023-03-07 | 景德镇学院 | Novel inorganic antibacterial agent and preparation method thereof |
-
2005
- 2005-06-20 CN CN 200510077234 patent/CN1290797C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN1693284A (en) | 2005-11-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103008676B (en) | Method for manufacturing high-dispersion ultrafine molybdenum-based powder | |
| CN104674048B (en) | A kind of Pt-Ru based high-temperature alloy material and preparation method thereof | |
| CN101074460A (en) | Method for processing tungsten alloy filament | |
| CN108580917B (en) | A method for preparing tungsten dispersion-strengthened copper ultrafine powder by low-temperature combustion synthesis | |
| CN1290797C (en) | Electronic emitting material of molybdenum rare earth containing cerium and preparation process thereof | |
| Tan et al. | A palladium-doped ceria@ carbon core–sheath nanowire network: a promising catalyst support for alcohol electrooxidation reactions | |
| CN1274456C (en) | Preparation method of multi-element composite rare earth-tungsten electrode material | |
| CN101447376B (en) | Y2O3-Lu2O3 system composite rare earth-molybdenum electron emission material and preparation method thereof | |
| TW201830758A (en) | Catalyst for polymer electrolyte fuel cell and method for producing the same | |
| CN103962154B (en) | A kind of NOx catalysis material and preparation method thereof and a kind of NOx catalysis electrode slurry | |
| CN104525962A (en) | Method for preparing nanoscale oxide dispersion strengthening iron-based composite powder | |
| CN1176480C (en) | High-current density electronic emission body rareearth-Sc-W based material and mfg. method thereof | |
| CN1889221A (en) | Composite rare earth doping Tungsten-base dispenser cathode containing scandium and producing method thereof | |
| CN1131330C (en) | Secondary-emission rare earth-molybdenum material and its preparing process | |
| CN104985194A (en) | Preparation method for oxide dispersion strengthening ferrite-cobalt nano-composite powder | |
| CN112176236A (en) | La2O3W-Mo-doped alloy material and preparation method thereof | |
| CN1416987A (en) | Discharge and plasma fast sintering process of preparing secondary composite RE-MO emitting material | |
| CN110560077A (en) | Iron-niobium medium-low temperature denitration catalyst with water-resistant and sulfur-resistant performance and preparation method and application thereof | |
| CN1616185A (en) | High-content multi-element composite rare earth tungsten electrode material and preparation method thereof | |
| CN106328468B (en) | The preparation method of magnetron La2O3 doping Mo cathode materials | |
| CN116043267A (en) | Ferronickel composite defect type molybdenum oxide electrocatalyst and preparation method and application thereof | |
| JP2005332662A (en) | Catalyst for fuel cell and its manufacturing method | |
| CN103700557B (en) | A kind of carbonization rare-earth oxidation lutetium doping molybdenum cathode material and preparation method thereof | |
| CN101447377B (en) | Y2O3-Gd2O3 system composite rare earth-molybdenum electron emission material and its preparation method | |
| CN106206216B (en) | Be carbonized La2O3 and the composite mixed Mo cathode materials of Lu2O3 and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |