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<table>The highest values <svg height="13.1104pt" id="M145" style="vertical-align:-3.4325pt" version="1.1" viewbox="-0.0498162 -9.6779 54.9041 13.1104" width="54.9041pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0135,0,0,-0.0135,0,0)"><path d="M449 634C442 637 425 643 405 650C376 660 341 666 307 666C181 666 98 590 98 485C98 400 170 343 215 310L246 288C307 243 343 204 343 147C343 67 291 18 219 18C104 18 61 124 51 202L23 199C28 124 27 71 27 47C47 22 122 -16 204 -16C324 -16 428 60 428 174C428 256 379 309 307 360L276 382C223 419 179 455 179 516C179 576 221 632 293 632C379 632 410 564 418 487L448 490C446 536 446 592 449 634Z" id="g113-84"></path><glyph.data ascent="3473" descent="-2876" horiz-adv-x="472" vert-adv-y="472"></glyph.data></g><g transform="matrix(.0095,0,0,-0.0095,6.327,3.264)"><path d="M810 0V30C751 35 744 40 744 106V296C744 396 694 451 614 451C583 451 558 438 537 425C512 409 485 391 454 368C434 420 390 451 342 451C309 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409V439H277V409C318 405 324 400 307 369C290 337 270 307 251 279L194 367C175 396 180 402 220 409V439H18V409C74 401 87 395 117 349L204 213C173 168 147 130 119 95C78 46 67 38 5 30V0H195V30C144 38 143 47 162 79C181 112 202 149 225 181L297 70C314 43 307 35 264 30V0H482Z" id="g58-118"></path><glyph.data ascent="1007" descent="-369" horiz-adv-x="481" vert-adv-y="481"></glyph.data></g></svg> observation in years (from 2008 to 2014) in lead-free BNKT-based ceramics.</table>

Advances in Materials Science and Engineering

fig3

Figure 3

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562 495L592 498Z"/></g><g transform="matrix(.018,0,0,-0.018,10.747,0)"><use xlink:href="#g190-106"/></g><g transform="matrix(.018,0,0,-0.018,15.54,0)"><path id="g190-80" d="M381 665C170 665 44 498 44 318C44 125 188 -15 369 -15C552 -15 703 117 703 333C703 534 550 665 381 665ZM359 629C491 629 601 517 601 306C601 114 502 21 390 21C249 21 146 158 146 346S248 629 359 629Z"/></g><g transform="matrix(.013,0,0,-0.013,29.008,4.308)"><path id="g22-49" d="M310 382C345 404 366 417 384 433C404 450 417 474 417 501C417 578 357 635 252 635H251C184 635 135 603 107 572L57 506L86 478C122 527 156 554 205 554C250 554 290 528 290 467S227 367 144 340L151 300C168 304 190 308 208 308C260 308 327 275 327 181C327 89 288 49 238 49C177 49 131 93 109 111C95 122 82 119 70 110C57 100 40 82 40 63C40 48 48 34 65 21C86 4 126 -12 177 -12C240 -12 460 60 460 222C460 298 409 363 310 380V382Z"/></g></svg>-Based Piezoelectric Materials 

Advances in Materials Science and Engineering

Current Development in Lead-Free -Based Piezoelectric Materials

Figure 3