Topological Aspects of Boron Nanotubes

<div>(a) A 2D sheet of boron triangular nanotube <span class="nowrap"><svg height="11.439pt" id="M44" style="vertical-align:-2.15067pt" version="1.1" viewbox="-0.0498162 -9.28833 46.6967 11.439" width="46.6967pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M372 352C427 368 507 407 507 502C507 548 486 592 451 616C420 638 376 650 301 650H44V622C124 616 128 610 128 527V123C128 40 122 34 36 28V0H257C336 0 402 12 453 40C512 72 548 124 548 191C548 291 471 335 372 350V352ZM213 362V558C213 591 216 602 226 608C235 614 258 618 282 618C377 618 415 558 415 490C415 406 369 362 260 362H213ZM213 328H258C380 328 450 283 450 181C450 76 377 35 296 34C231 34 213 53 213 125V328Z" id="g190-67"></path></g><g transform="matrix(.013,0,0,-0.013,7.514,0)"><path d="M592 498C586 556 582 629 581 675H560C545 656 537 650 510 650H115C87 650 74 652 60 675H40C38 620 33 555 28 495H57C69 539 77 568 89 585C102 607 122 616 205 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Advances in Materials Science and Engineering

Topological Aspects of Boron Nanotubes

Figure 2